bluuebunny/crossref_metadata_2025 huggingface dataset:
RNA Interference-Mediated Targeting of Human Cytomegalovirus Immediate-Early or Early Gene Products Inhibits Viral Replication with Differential Effects on Cellular Functions
Authors: E Xiaofei , Stadler Bradford M. , Debatis Michelle , Wang Shixia , Lu Shan , Kowalik Timothy F.
Published: March 2012

Viral drug toxicity, resistance, and an increasing immunosuppressed population warrant continued research into new avenues for limiting diseases associated with human cytomegalovirus (HCMV). In this study, a small interfering RNA (siRNA), siX3, was designed to target coding sequences within shared exon 3 of
UL123
and
UL122
transcripts encoding IE1 and IE2 immediate-early proteins of HCMV. Pretreatment of cells with siX3 reduced the levels of viral protein expression, DNA replication, and progeny virus production compared to control siRNA. Two siRNAs against
UL54
and overlapping transcripts (
UL55-57
) were compared to siX3 in HCMV infection and were also found to be effective at inhibiting HCMV replication. Further investigation into the effects of the siRNAs on viral replication showed that pretreatment with each of the siRNAs resulted in an inhibition in the formation of mature replication compartments. The ability of these siRNAs to prevent or reduce certain cytopathic effects associated with HCMV infection was also examined. Infected cells pretreated with siX3, but not siUL54, retained promyelocytic leukemia (PML) protein in cellular PML bodies, an essential component of this host intrinsic antiviral defense. DNA damage response proteins, which are localized in nuclear viral replication compartments, were reduced in the siX3- and siUL54-treated cells. siX3, but not siUL54, prevented DNA damage response signaling early after infection. Therapeutic efficacy was demonstrated by treating cells with siRNAs after HCMV replication had commenced. Together, these findings suggest that siRNAs targeting exon 3 of the major
IE
genes or the
UL54-57
transcripts be further studied for their potential development into anti-HCMV therapeutics.
Visualizing Coronavirus RNA Synthesis in Time by Using Click Chemistry
Authors: Hagemeijer Marne C. , Vonk Annelotte M. , Monastyrska Iryna , Rottier Peter J. M. , de Haan Cornelis A. M.
Published: March 2012

Coronaviruses induce in infected cells the formation of replicative structures, consisting of double-membrane vesicles (DMVs) and convoluted membranes, where viral RNA synthesis supposedly takes place and to which the nonstructural proteins (nsp's) localize. Double-stranded RNA (dsRNA), the presumed intermediate in RNA synthesis, is localized to the DMV interior. However, as pores connecting the DMV interior with the cytoplasm have not been detected, it is unclear whether RNA synthesis occurs at these same sites. Here, we studied coronavirus RNA synthesis by feeding cells with a uridine analogue, after which nascent RNAs were detected using click chemistry. Early in infection, nascent viral RNA and nsp's colocalized with or occurred adjacent to dsRNA foci. Late in infection, the correlation between dsRNA dots, then found dispersed throughout the cytoplasm, and nsp's and nascent RNAs was less obvious. However, foci of nascent RNAs were always found to colocalize with the nsp12-encoded RNA-dependent RNA polymerase. These results demonstrate the feasibility of detecting viral RNA synthesis by using click chemistry and indicate that dsRNA dots do not necessarily correspond with sites of active viral RNA synthesis. Rather, late in infection many DMVs may harbor dsRNA molecules that are no longer functioning as intermediates in RNA synthesis.
Suppression of Injuries Caused by a Lytic RNA Virus (Mengovirus) and Their Uncoupling from Viral Reproduction by Mutual Cell/Virus Disarmament
Authors: Mikitas Olga V. , Ivin Yuri Y. , Golyshev Sergey A. , Povarova Natalia V. , Galkina Svetlana I. , Pletjushkina Olga Y. , Nadezhdina Elena S. , Gmyl Anatoly P. , Agol Vadim I.
Published: March 2012

Viruses often elicit cell injury (cytopathic effect [CPE]), a major cause of viral diseases. CPE is usually considered to be a prerequisite for and/or consequence of efficient viral growth. Recently, we proposed that viral CPE may largely be due to host defensive and viral antidefensive activities. This study aimed to check the validity of this proposal by using as a model HeLa cells infected with mengovirus (MV). As we showed previously, infection of these cells with wild-type MV resulted in necrosis, whereas a mutant with incapacitated antidefensive (“security”) viral leader (L) protein induced apoptosis. Here, we showed that several major morphological and biochemical signs of CPE (e.g., alterations in cellular and nuclear shape, plasma membrane, cytoskeleton, chromatin, and metabolic activity) in cells infected with L−mutants in the presence of an apoptosis inhibitor were strongly suppressed or delayed for long after completion of viral reproduction. These facts demonstrate that the efficient reproduction of a lytic virus may not directly require development of at least some pathological alterations normally accompanying infection. They also imply that L protein is involved in the control of many apparently unrelated functions. The results also suggest that the virus-activated program with competing necrotic and apoptotic branches is host encoded, with the choice between apoptosis and necrosis depending on a variety of intrinsic and extrinsic conditions. Implementation of this defensive suicidal program could be uncoupled from the viral reproduction. The possibility of such uncoupling has significant implications for the pathogenesis and treatment of viral diseases.
Targeting of Dicer-2 and RNA by a Viral RNA Silencing Suppressor in Drosophila Cells
Authors: Qi Nan , Zhang Lei , Qiu Yang , Wang Zhaowei , Si Jie , Liu Yongxiang , Xiang Xue , Xie Jiazheng , Qin Cheng-Feng , Zhou Xi , Hu Yuanyang
Published: March 2012

RNA interference (RNAi) is a eukaryotic gene-silencing mechanism that functions in antiviral immunity in diverse organisms. To combat RNAi-mediated immunity, viruses encode viral suppressors of RNA silencing (VSRs) that target RNA and protein components in the RNAi machinery. Although the endonuclease Dicer plays key roles in RNAi immunity, little is known about how VSRs target Dicer. Here, we show that the B2 protein from Wuhan nodavirus (WhNV), the counterpart of Flock House virus (FHV), suppresses
Drosophila melanogaster
RNAi by directly interacting with Dicer-2 (Dcr-2) and sequestering double-stranded RNA (dsRNA) and small interfering RNA (siRNA). Further investigations reveal that WhNV B2 binds to the RNase III and Piwi-Argonaut-Zwille (PAZ) domains of Dcr-2 via its C-terminal region, thereby blocking the activities of Dcr-2 in processing dsRNA and incorporating siRNA into the RNA-induced silencing complex (RISC). Moreover, we uncover an interrelationship among diverse activities of WhNV B2, showing that RNA binding enhances the B2–Dcr-2 interaction by promoting B2 homodimerization. Taken together, our findings establish a model of suppression of
Drosophila
RNAi by WhNV B2 targeting both Dcr-2 and RNA and provide evidence that an interrelationship exists among diverse activities of VSRs to antagonize RNAi.
Sickle cell trait associated with a RR of death of 37 times in national collegiate athletic association football athletes: a database with 2 million athlete-years as the denominator
Authors: Harmon Kimberly G , Drezner Jonathan A , Klossner David , Asif Irfan M
Published: March 2012

Background

This study examines sickle cell trait (SCT) as a cause of sudden death in National Collegiate Athletic Association (NCAA) athletes and explores the cost-effectiveness of different screening models.

Methods

The authors reviewed the cause of all cases of sudden death in NCAA student-athletes from January 2004 through December 2008. The authors also explored the cost-effectiveness of screening for this condition in selected populations assuming that identifying athletes with SCT would prevent death.

Results

There were 273 deaths and a total of 1 969 663 athlete-participant-years. Five (2%) deaths were associated with SCT. In football athletes, there were 72 (26%) deaths. Of these, 52 (72%) were due to trauma unrelated to sports activity and 20 (28%) were due to medical causes; nine deaths were cardiac (45%), five were associated with SCT (25%). Thirteen of the 20 deaths due to medical causes occurred during exertion; cardiac (6, 46%) SCT associated (5, 39%), and heat stroke unrelated to SCT (2, 15%). All deaths associated with SCT occurred in black Division I football athletes. The risk of exertional death in Division I football players with SCT was 1:827 which was 37 times higher than in athletes without SCT. The cost per case identified varied widely depending on the population screened and the price of the screening test.

Conclusions

Exertional death in athletes with SCT occurs at a higher rate than previously appreciated. More research is needed to (1) understand the pathophysiology of death in SCT-positive athletes and (2) determine whether screening high-risk populations reduces mortality.
Serial multiple biomarkers in the assessment of suspected acute coronary syndrome: multiple infarct markers in chest pain (MIMIC) study
Authors: Macdonald Stephen PJ , Nagree Yusuf , Fatovich Daniel M , Phillips Michael , Brown Simon GA
Published: March 2012

Objective

To evaluate the accuracy of a 2-h serial multiple biomarker (SMB) protocol for exclusion of myocardial infarction (MI) in the Emergency Department.

Methods

A prospective, multicentre, observational study enrolled patients undergoing evaluation for possible MI. Blood samples at presentation and 2 h later were analysed for myoglobin, creatinine kinase-MB, troponin-I and B-natriuretic peptide. Thrombolysis in Myocardial Infarction (TIMI) score and National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand (NHF/CSANZ) guideline for acute coronary syndrome were used to determine clinical risk. Primary outcome was MI diagnosed at index presentation. Secondary outcome was composite of all-cause mortality, MI and previously unplanned coronary revascularisation within 30 days.

Results

1758 patients were recruited. 168 (11%) of 1501 with data sufficient for analysis had MI, and 223 (14%) of 1620 had a secondary outcome. SMB sensitivity and specificity were 0.90 (95% CI 0.84 to 0.94) and 0.41 (95% CI 0.39 to 0.44) for MI. For 30-day outcome, SMB sensitivity and specificity were 0.84 (95% CI 0.78 to 0.88) and 0.41 (95% CI 0.39 to 0.44), compared with standard 8–12 h troponin sensitivity and specificity of 0.79 (95% CI 0.73 to 0.84) and 0.96 (95% CI 0.95 to 0.97). Combined with risk scores, SMB had sensitivity and specificity for MI of 0.99 (0.96 to 1.00) and 0.11 (95% CI 0.09 to 0.12) for TIMI score 0, compared with 0.98 (95% CI 0.94 to 0.99) and 0.31 (95% CI 0.29 to 0.34) for NHF/CSANZ low/intermediate risk groups.

Conclusions

SMB alone is not sufficiently sensitive to exclude MI. Combined with risk scoring, SMB appears to identify patients at lower risk. This requires prospective validation.
ON THE STRUCTURE OF HOMOGENENOUS WICK IDEALS IN WICK *-ALGEBRAS WITH BRAIDED COEFFICIENTS
Authors: OSTROVSKYI VASYL , PROSKURIN DANIIL , SAVCHUK YURII , TUROWSKA LYUDMILA
Published: March 2012

We study a Wick ideal structure of quadratic *-algebras allowing Wick ordering with braided operator of coefficients. A construction of nested sequence of homogeneous Wick ideals of growing degree is presented. Representations of a Wick analogue of the CCR algebra with two degrees of freedom, annihilating certain homogeneous Wick ideals are described.
STABLE ULRICH BUNDLES
Authors: CASANELLAS MARTA , HARTSHORNE ROBIN , GEISS FLORIAN , SCHREYER FRANK-OLAF
Published: March 2012

The existence of stable ACM vector bundles of high rank on algebraic varieties is a challenging problem. In this paper, we study stable Ulrich bundles (that is, stable ACM bundles whose corresponding module has the maximum number of generators) on nonsingular cubic surfaces X ⊂ ℙ3. We give necessary and sufficient conditions on the first Chern class D for the existence of stable Ulrich bundles on X of rank r and c1= D. When such bundles exist, we prove that the corresponding moduli space of stable bundles is smooth and irreducible of dimension D2- 2r2+ 1 and consists entirely of stable Ulrich bundles (see Theorem 1.1). We are also able to prove the existence of stable Ulrich bundles of any rank on nonsingular cubic threefolds in ℙ4, and we show that the restriction map from bundles on the threefold to bundles on the surface is generically étale and dominant.
GRANULAR TURBULENCE IN TWO DIMENSIONS: MICROSCALE REYNOLDS NUMBER AND FINAL CONDENSED STATES
Authors: ISOBE MASAHARU
Published: March 2012

Granular gases from the viewpoint of "two-dimensional turbulence" are investigated. In the quasi-elastic and thermodynamic limit, we obtained clear evidence for an enstrophy (square of vorticity) cascade and -3 exponent in the Kraichnan–Leith–Bachelor energy spectrum by performing large-scale (N ~ 16.8 million number of disks) event-driven molecular dynamics simulations. In these calculations, the enstrophy dissipation rate showed a strong relationship with the evolution of the exponent in the energy spectrum. The growth of the Reynolds number based on the microscale confirmed that the enstrophy cascade regime was that of fully developed turbulence. Moreover, a condensed state resembling Bose–Einstein condensation in decaying two-dimensional Navier–Stokes turbulence also appeared as the final attractor of the evolving granular gas in the long time limit.
LOCAL D3/D7 μ-SPLIT SUSY, 125 GeV HIGGS AND LARGE VOLUME RICCI-FLAT SWISS-CHEESE METRICS: A BRIEF REVIEW
Authors: MISRA AALOK
Published: March 2012

In this paper, we review briefly recent progress made in realizing local(ized around a mobile spacetime filling D3-brane in) D3/D7 μ-split Supersymmetry in (the large volume limit of Type IIB) String Theory (compactified on Swiss-Cheese Calabi–Yau orientifolds) as well as obtaining a 125 GeV (light) Higgs in the same setup. We also discuss obtaining the geometric Kähler potential (and hence the Ricci-flat metric) for the Swiss-Cheese Calabi–Yau in the large volume limit using the Donaldson's algorithm and intuition from GLSM-based calculations — we present new results for Swiss-Cheese Calabi–Yau (used in the setup) metrics at points finitely away from the "big" divisor.
ON DETERMINATION OF THE GEOMETRIC COSMOLOGICAL CONSTANT FROM THE OPERA EXPERIMENT OF SUPERLUMINAL NEUTRINOS
Authors: YAN MU-LIN , HU SEN , HUANG WEI , XIAO NENG-CHAO
Published: March 2012

The recent OPERA experiment of superluminal neutrinos has deep consequences in cosmology. In cosmology a fundamental constant is the cosmological constant. From observations one can estimate the effective cosmological constant Λ eff which is the sum of the quantum zero point energy Λ dark energy and the geometric cosmological constant Λ. The OPERA experiment can be applied to determine the geometric cosmological constant Λ. It is the first study to distinguish the contributions of Λ and Λ dark energy from each other by experiment. The determination is based on an explanation of the OPERA experiment in the framework of Special Relativity with de Sitter spacetime symmetry.
AN INTEGRO-DIFFERENTIAL CONSERVATION LAW ARISING IN A MODEL OF GRANULAR FLOW
Authors: AMADORI DEBORA , SHEN WEN
Published: March 2012

We study a scalar integro-differential conservation law which was recently derived by the authors as the slow erosion limit of a granular flow. Considering a set of more general erosion functions, we study the initial boundary value problem for which one cannot adapt the standard theory of conservation laws. We construct approximate solutions with a fractional step method, by recomputing the integral term at each time step. A prioriL∞bound and total variation estimates yield the convergence and global existence of solutions with bounded variation. Furthermore, we present a well-posedness analysis which establishes that these solutions are stable in the L1norm with respect to the initial data.
LOCAL EXISTENCE AND UNIQUENESS THEORY FOR THE SECOND SOUND EQUATION IN ONE SPACE DIMENSION
Authors: KATO KEIICHI , SUGIYAMA YUUSUKE
Published: March 2012

We study the local-in-time existence and uniqueness of the Cauchy problem for the nonlinear wave equation [Formula: see text], which is called the second sound equation. Assuming that u(0, x) = φ ≥ A > 0, φ ∈ C1, and ∂xφ ∈ Hs, we establish the uniqueness of solutions without restriction on their amplitude.
Electron affinity states of metal supported phthalocyanines measured by tunneling spectroscopy
Authors: Hipps K.W. , Mazur Ursula
Published: March 2012

Orbital Mediated Tunneling Spectroscopy OMTS (elastic electron tunneling) was employed in measuring electron affinity levels (EA) of unsubstituted, alkylated, sulfonated, and metalated phthalocyanines (Pc) adsorbed as single molecules or aggregates on metal substrates and imbedded in metal-insulator-metal (M-I-M) devices. MPc complexes were vapor deposited, solution phase doped, or transferred as Langmuir–Blodgett films. It was determined that while the nature of the substituents has a large effect on the gas phase electron affinities, they play a minimal role on the electron affinities of metal supported phthalocyanines. Moreover, the orientation of monolayer films and the method of film deposition (vapor, solution, Langmuir–Blodgett) also appear to play only a minor role in determining the electron affinities. Electrochemical reduction potentials obtained for the solution phase molecular systems are compared to the OMTS data and a strong correlation is observed. In contrast, the predicted EA values for the gas phase molecules show little correspondence with their OMTS equivalents for adsorbed phthalocyanines. Inelastic scattering from phthalocyanine π→π* transitions and metal centered d–d transitions are observed for chromophores imbedded in tunnel diodes. Both the observed lowest spin forbidden transitions and the calculated gas phase HOMO–LUMO gaps are only weakly affected by Pc substitution and surface orientation.
THE DYNAMICS OF A DISCRETE SEIT MODEL WITH AGE AND INFECTION AGE STRUCTURES
Authors: CAO HUI , XIAO YANNI , ZHOU YICANG
Published: March 2012

Age and infection age have significant influence on the transmission of infectious diseases, such as HIV/AIDS and TB. A discrete SEIT model with age and infection age structures is formulated to investigate the dynamics of the disease spread. The basic reproduction number R0is defined and used as the threshold parameter to characterize the disease extinction or persistence. It is shown that the disease-free equilibrium is globally stable if R0< 1, and it is unstable if R0> 1. When R0> 1, there exists an endemic equilibrium, and the disease is uniformly persistent. The stability of the endemic equilibrium is investigated numerically.
Photo-Leakage Current of Thin-Film Transistors with ZnO Channels Formed at Various Oxygen Partial Pressures under Visible Light Irradiation
Authors: Shimakawa Shin-ichi , Kamada Yudai , Kawaharamura Toshiyuki , Wang Dapeng , Li Chaoyang , Fujita Shizuo , Hirao Takashi , Furuta Mamoru
Published: March 2012

The effects of the oxygen partial pressure [p(O2)] during ZnO sputtering on the photo-leakage current of a ZnO thin-film transistor (TFT) were investigated. The photo-leakage current increased with decreasing p(O2). When the photon energy of incident light is smaller than the band-gap of the ZnO, electrons are excited from the trapped states existing near the valence band. It was found that the density of the electron traps increased when the p(O2) decreased. Moreover, the trap states were formed at ∼0.5 eV and 2.8–3.2 eV from the conduction band (E
C) when the p(O2) decreased. The traps formed at (E
C-E) of ∼0.5 eV affect the subthreshold characteristics in the dark state, while the traps formed at (E
C-E) of 2.8–3.2 eV affect the photo-leakage current of the ZnO TFTs.
Effective Medium Theory for Calculating Reflectance from Metal–Dielectric Multilayered Structure
Authors: Kameda Shinji , Mizutani Akio , Kikuta Hisao
Published: March 2012

An effective medium theory (EMT) for calculating optical reflectance from a surface of metal-and-dielectric multilayered structures (MDMS) has been described. MDMS is a strongly-anisotropic optical medium of which the dispersion surface is cylindrical for transverse-magnetic (TM) polarized light. A coefficient of reflection has been derived by applying the dispersion surface of MDMS to the phase-matching condition and the boundary conditions at the interface between an isotropic medium and the MDMS. The reflectance calculated by this anisotropic effective medium theory has agreed with the results by the finite-difference time-domain (FDTD) method, even for oblique incidence. Moreover, transmittance and reflectance from a finite thick MDMS layer are also derived by using the effective medium theory.
Improvement of Electrostatic Discharge Protection by Introducing a Spindt-Type Silicon Field Emission Device
Authors: Chang Liann-Be , Ferng Yi-Cherng , Liao Jhong-Wei , Lin Ching-Chi
Published: March 2012

In this paper, an original Spindt-type silicon field emission device (FED) with electrostatic discharge (ESD) regulation capability is proposed. The fabricated FED characteristics, including process parameters, capacitance–voltage (C–V), current–voltage (I–V), and frequency response, are investigated. To verify its capability of ESD protection, we replace the metal oxide varistor (MOV) in a state-of-the-art protection configuration with the fabricated FED under the application conditions of system-level ESD tests. The measured results show that the proposed ESD protection circuit composed of a prestage gas arrestor, an intermediate resistor, and an introduced FED can suppress an injected ESD pulse voltage of 6000 to 3193 V, a reduction of 46.8%, whereas suppression is to 5606 V, a reduction of 6.57%, when using only a gas arrestor.
n-Channel Metal–Oxide–Semiconductor Field-Effect Transistor Modeling in Forward Body Bias Condition for Low Voltage Complementary Metal–Oxide–Semiconductor Circuits Design
Authors: Aoki Hitoshi , Matsuzawa Akira
Published: March 2012

This paper proposes a modified transistor model to improve the accuracy under the forward body bias operation that is vital for low voltage circuits, such as 0.5 V, to reduce the power consumption of complementary metal–oxide–semiconductor (CMOS) LSI. The proposed model and equations were implemented in BSIM4 version 4.6 with SPICE3f5 and verified by measurements of 60 nm n-channel metal–oxide–semiconductor field-effect transistors (n-MOSFETs). Approximately 50% inaccuracy of the drain current can be corrected. Furthermore, the importance of the proposed model will become higher with further lower threshold voltage operation requirements.
Growth of Epitaxial Anatase TiO2(001) Thin Film on NaCl(001) Substrate by Ion Beam Sputtering and Thermal Annealing
Authors: Kao Chung-Ho , Tsai Jia-Hong , Yeh Sung-Wei , Huang Hsing-Lu , Gan Dershin , Shen Pouyan
Published: March 2012

The anatase TiO2(001) surface was shown to have superior photoreactivity. Epitaxial anatase (001) films used to be grown on single-crystal SrTiO3 and LaAlO3 substrates. It is shown in this report that these films can be grown also on the NaCl substrate, which is much cheaper and easily prepared. Epitaxial TiO(001) films were first grown on the NaCl(001) substrate. By testing the TiO-to-anatase transformation over temperature and time ranges, an epitaxial anatase (001) film was prepared by simple thermal oxidation in air. The formation of a single-variant anatase (001) film instead of a multiple-variant film is discussed in this report.
Interactive dynamics for visual analysis
Authors: Heer Jeffrey , Shneiderman Ben
Published: March 2012

A taxonomy of tools that support the fluent and flexible use of visualizations.
What agile teams think of agile principles
Authors: Williams Laurie
Published: March 2012

Even after almost a dozen years, they still deliver solid guidance for software development teams and their projects.
Rag GTPases and AMPK/TSC2/Rheb mediate the differential regulation of mTORC1 signaling in response to alcohol and leucine
Authors: Hong-Brown Ly Q. , Brown C. Randell , Kazi Abid A. , Navaratnarajah Maithili , Lang Charles H.
Published: March 2012

Leucine (Leu) and insulin both stimulate muscle protein synthesis, albeit at least in part via separate signaling pathways. While alcohol (EtOH) suppresses insulin-stimulated protein synthesis in cultured myocytes, its ability to disrupt Leu signaling and Rag GTPase activity has not been determined. Likewise, little is known regarding the interaction of EtOH and Leu on the AMPK/TSC2/Rheb pathway. Treatment of myocytes with EtOH (100 mM) decreased protein synthesis, whereas Leu (2 mM) increased synthesis. In combination, EtOH suppressed the anabolic effect of Leu. The effects of EtOH and Leu were associated with coordinate changes in the phosphorylation state of mTOR, raptor, and their downstream targets 4EBP1 and S6K1. As such, EtOH suppressed the ability of Leu to activate these signaling components. The Rag signaling pathway was activated by Leu but suppressed by EtOH, as evidenced by changes in the interaction of Rag proteins with mTOR and raptor. Overexpression of constitutively active (ca)RagA and caRagC increased mTORC1 activity, as determined by increased S6K1 phosphorylation. Furthermore, the caRagA-caRagC heterodimer blocked the inhibitory effect of EtOH. EtOH and Leu produced differential effects on AMPK signaling. EtOH enhanced AMPK activity, resulting in increased TSC2 (S1387) and eEF2 phosphorylation, whereas Leu had the opposite effect. EtOH also decreased the interaction of Rheb with mTOR, and this was prevented by Leu. Collectively, our results indicate that EtOH inhibits the anabolic effects that Leu has on protein synthesis and mTORC1 activity by modulating both Rag GTPase function and AMPK/TSC2/Rheb signaling.
Evidence that renal arginine transport is impaired in spontaneously hypertensive rats
Authors: Rajapakse N. W. , Kuruppu S. , Hanchapola I. , Venardos K. , Mattson D. L. , Smith A. I. , Kaye D. M. , Evans R. G.
Published: March 2012

Low renal nitric oxide (NO) bioavailability contributes to the development and maintenance of chronic hypertension. We investigated whether impaired l-arginine transport contributes to low renal NO bioavailability in hypertension. Responses of renal medullary perfusion and NO concentration to renal arterial infusions of the l-arginine transport inhibitor l-lysine (10 μmol·kg−1·min−1; 30 min) and subsequent superimposition of l-arginine (100 μmol·kg−1·min−1; 30 min), the NO synthase inhibitor NG-nitro-l-arginine (2.4 mg/kg; iv bolus), and the NO donor sodium nitroprusside (0.24 μg·kg−1·min−1) were examined in Sprague-Dawley rats (SD) and spontaneously hypertensive rats (SHR). Renal medullary perfusion and NO concentration were measured by laser-Doppler flowmetry and polarographically, respectively, 5.5 mm below the kidney surface. Renal medullary NO concentration was less in SHR (53 ± 3 nM) compared with SD rats (108 ± 12 nM; P = 0.004). l-Lysine tended to reduce medullary perfusion (−15 ± 7%; P = 0.07) and reduced medullary NO concentration (−9 ± 3%; P = 0.03) while subsequent superimposition of l-arginine reversed these effects of l-lysine in SD rats. In SHR, l-lysine and subsequent superimposition of l-arginine did not significantly alter medullary perfusion or NO concentration. Collectively, these data suggest that renal l-arginine transport is impaired in SHR. Renal l-[3H]arginine transport was less in SHR compared with SD rats ( P = 0.01). Accordingly, we conclude that impaired arginine transport contributes to low renal NO bioavailability observed in the SHR kidney.
The measurement of endogenous carbon monoxide production
Authors: Coburn Ronald F.
Published: March 2012

Recent findings that heme oxygenase-1 can be induced by oxidative stress and inflammation in many different cellular systems, and that carbon monoxide (CO) produced as a by-product of this enzyme is a signaling molecule, have generated a major research area with hundreds of studies published over the last few years. The measurement of expired CO concentration has been used in humans as a biomarker of induced heme oxygenase resulting from inflammation or oxidative stress, but a precise method of measuring endogenous CO production that can be easily used to study patients is needed. The present study describes such a method. The described method allows calculation of the rate of heme catabolism with a precision of ±2 μmol/h, ∼10% of the mean normal rate in subjects used in this investigation. This method, which is subject-patient friendly, precise, and inexpensive to perform, should be applicable to studies performed on humans with induced heme oxygenase and studies of effects of therapy for inflammatory and hemolytic diseases.
Modulation of neuronal sodium channels by the sea anemone peptide BDS-I
Authors: Liu Pin , Jo Sooyeon , Bean Bruce P.
Published: March 2012

Blood-depressing substance I (BDS-I), a 43 amino-acid peptide from sea anemone venom, is used as a specific inhibitor of Kv3-family potassium channels. We found that BDS-I acts with even higher potency to modulate specific types of voltage-dependent sodium channels. In rat dorsal root ganglion (DRG) neurons, 3 μM BDS-I strongly enhanced tetrodotoxin (TTX)-sensitive sodium current but weakly inhibited TTX-resistant sodium current. In rat superior cervical ganglion (SCG) neurons, which express only TTX-sensitive sodium current, BDS-I enhanced current elicited by small depolarizations and slowed decay of currents at all voltages (EC50∼ 300 nM). BDS-I acted with exceptionally high potency and efficacy on cloned human Nav1.7 channels, slowing inactivation by 6-fold, with an EC50of approximately 3 nM. BDS-I also slowed inactivation of sodium currents in N1E-115 neuroblastoma cells (mainly from Nav1.3 channels), with an EC50∼ 600 nM. In hippocampal CA3 pyramidal neurons (mouse) and cerebellar Purkinje neurons (mouse and rat), BDS-I had only small effects on current decay (slowing inactivation by 20–50%), suggesting relatively weak sensitivity of Nav1.1 and Nav1.6 channels. The biggest effect of BDS-I in central neurons was to enhance resurgent current in Purkinje neurons, an effect reflected in enhancement of sodium current during the repolarization phase of Purkinje neuron action potentials. Overall, these results show that BDS-I acts to modulate sodium channel gating in a manner similar to previously known neurotoxin receptor site 3 anemone toxins but with different isoform sensitivity. Most notably, BDS-I acts with very high potency on human Nav1.7 channels.
Human neural responses involved in spatial pooling of locally ambiguous motion signals
Authors: Amano Kaoru , Takeda Tsunehiro , Haji Tomoki , Terao Masahiko , Maruya Kazushi , Matsumoto Kenji , Murakami Ikuya , Nishida Shin'ya
Published: March 2012

Early visual motion signals are local and one-dimensional (1-D). For specification of global two-dimensional (2-D) motion vectors, the visual system should appropriately integrate these signals across orientation and space. Previous neurophysiological studies have suggested that this integration process consists of two computational steps (estimation of local 2-D motion vectors, followed by their spatial pooling), both being identified in the area MT. Psychophysical findings, however, suggest that under certain stimulus conditions, the human visual system can also compute mathematically correct global motion vectors from direct pooling of spatially distributed 1-D motion signals. To study the neural mechanisms responsible for this novel 1-D motion pooling, we conducted human magnetoencephalography (MEG) and functional MRI experiments using a global motion stimulus comprising multiple moving Gabors (global-Gabor motion). In the first experiment, we measured MEG and blood oxygen level-dependent responses while changing motion coherence of global-Gabor motion. In the second experiment, we investigated cortical responses correlated with direction-selective adaptation to the global 2-D motion, not to local 1-D motions. We found that human MT complex (hMT+) responses show both coherence dependency and direction selectivity to global motion based on 1-D pooling. The results provide the first evidence that hMT+ is the locus of 1-D motion pooling, as well as that of conventional 2-D motion pooling.
A Randomised, Double-Blind Pilot Study of Enzyme-Potentiated Desensitisation for Prophylaxis of Large Local Reactions to Mosquito Bites
Authors: Berkovitz S. , Hill N. , Radcliffe M. , Ambler G.
Published: March 2012

Primary Objective. To test the hypothesis that two injections of enzyme-potentiated mosquito antigen significantly reduce the size of experimental mosquito bites in participants with LLR-MB. Design. Randomised, double-blind, placebo-controlled, parallel group comparison over 3 months. Setting. Hospital outpatient clinic. Participants. Fifty adult participants of both sexes. Interventions. Two injections of mosquito antigen or matching placebo, 6 weeks apart. Main Outcome Measures. Early (1 hour) and late (24 hours) mean square root of erythema area (SREA) following controlled mosquito bite with the second bite given at least 6 weeks following the final injection. Results. At 1 hour, mean SREA was slightly higher in the EPD group compared to placebo after adjusting for baseline values (0.46, 95% CI −6.11 to 7.03), but this was not statistically significant (P=0.89, ANCOVA analysis); neither were the results at 24 hours (−2.58, 95% CI −11.73 to 6.57) (P=0.57). The proportion of participants experiencing a decrease in wheal size at 1 or 24 hours was similar between groups. Conclusions. EPD was not demonstrated to be effective for immediate or delayed LLR-MB. Methodological problems included a high variability in LLR-MB between subjects, suggesting that a crossover design should be used in future.
Advances in Wound Healing: A Review of Current Wound Healing Products
Authors: Murphy Patrick S. , Evans Gregory R. D.
Published: March 2012

Successful wound care involves optimizing patient local and systemic conditions in conjunction with an ideal wound healing environment. Many different products have been developed to influence this wound environment to provide a pathogen-free, protected, and moist area for healing to occur. Newer products are currently being used to replace or augment various substrates in the wound healing cascade. This review of the current state of the art in wound-healing products looks at the latest applications of silver in microbial prophylaxis and treatment, including issues involving resistance and side effects, the latest uses of negative pressure wound devices, advanced dressings and skin substitutes, biologic wound products including growth factor applications, and hyperbaric oxygen as an adjunct in wound healing. With the abundance of available products, the goal is to find the most appropriate modality or combination of modalities to optimize healing.
Network-Based Gene Expression Biomarkers for Cold and Heat Patterns of Rheumatoid Arthritis in Traditional Chinese Medicine
Authors: Lu Cheng , Niu Xuyan , Xiao Cheng , Chen Gao , Zha Qinglin , Guo Hongtao , Jiang Miao , Lu Aiping
Published: March 2012

In Traditional Chinese Medicine (TCM), patients with Rheumatoid Arthritis (RA) can be classified into two main patterns: cold-pattern and heat-pattern. This paper identified the network-based gene expression biomarkers for both cold- and heat-patterns of RA. Gene expression profilings of CD4+ T cells from cold-pattern RA patients, heat-pattern RA patients, and healthy volunteers were obtained using microarray. The differentially expressed genes and related networks were explored using DAVID, GeneSpring software, and the protein-protein interactions (PPI) method. EIF4A2, CCNT1, and IL7R, which were related to the up-regulation of cell proliferation and the Jak-STAT cascade, were significant gene biomarkers of the TCM cold pattern of RA. PRKAA1, HSPA8, and LSM6, which were related to fatty acid metabolism and the I-κB kinase/NF-κB cascade, were significant biomarkers of the TCM heat-pattern of RA. The network-based gene expression biomarkers for the TCM cold- and heat-patterns may be helpful for the further stratification of RA patients when deciding on interventions or clinical trials.
Effect of Additives on Characterization and Photocatalytic Activity of /ZnO Nanocomposite Prepared via Sol-Gel Process
Authors: Moradi Shahram , Aberoomand Azar Parviz , Raeis Farshid Sanaz , Abedini Khorrami Saeed , Givianrad Mohammad Hadi
Published: March 2012

TiO2/ZnO nanocomposites were prepared by the sol-gel method with and without addatives such as carboxy methyl cellulose (CMC), poly(ethylene glycol) (PEG), polyvinylpyrrolidon, (PVP), and hydroxylpropylcellulose (HPC). The characteristics of the prepared TiO2/ZnO nanocomposites were identified by IR spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) methods. The additives have a significant effect on the particle size distribution and photocatalytic activity of TiO2/ZnO nanocomposites. The photocatalytic activity of the synthesized nanocomposites was investigated for decolorization of methyl orange (MO) in water under UV-irradiation in a batch reactor and the results showed that the photocatalytic activity of the nanocomposites have been increased by CMC, PEG, PVP, and HPC, respectively. SEM has shown that the particle size distribution of TiO2/ZnO nanocomposite in the presence of HPC was better than the other samples.
Performance Analysis of Flow-Based Traffic Splitting Strategy on Cluster-Mesh Sensor Networks
Authors: She Huimin , Lu Zhonghai , Jantsch Axel , Zhou Dian , Zheng Li-Rong
Published: March 2012

Performance analysis is crucial for designing predictable and cost-efficient sensor networks. Based on the network calculus theory, we propose a flow-based traffic splitting strategy and its analytical method for worst-case performance analysis on cluster-mesh sensor networks. The traffic splitting strategy can be used to alleviate the problem of uneven network traffic load. The analytical method is able to derive close-form formulas for the worst-case performance in terms of the end-to-end least upper delay bounds for individual flows, the least upper backlog bounds, and power consumptions for individual nodes. Numerical results and simulations are conducted to show benefits of the splitting strategy as well as validate the analytical method. The numerical results show that the splitting strategy enables much better balance on network traffic load and power consumption. Moreover, the simulation results verify that the theoretic bounds are fairly tight.
Routing in IPv6 over Low-Power Wireless Personal Area Networks (6LoWPAN): A Survey
Authors: Kumar Vinay , Tiwari Sudarshan
Published: March 2012

6LoWPANs (IPv6-based Low-Power Personal Area Networks) are formulated by devices that are compatible with the IEEE 802.15.4 standard. To moderate the effects of network mobility, the Internet Protocol (IP) does not calculate routes; it is left to a routing protocol, which maintains routing tables in the routers. 6LowPAN uses an adaptation layer between the network (IPv6) and data link layer (IEEE802.15.4 MAC) to fragment and reassemble IPv6 packets. The routing in 6LoWPAN is primarily divided on the basis of routing decision taken on adaptation or network layer. The objective of this paper is to present a state-of-the-art survey of existing routing protocols: LOAD, M-LOAD, DYMO-Low, Hi-Low, Extended Hi-Low, and S-AODV. These routing protocols have compared on the basis of different metric like energy consumption, memory uses, mobility, scalability, routing delay, an RERR message, a Hello message, and local repair. We have also presented the taxonomy of routing requirement; parameter for evaluating routing algorithm, and it was found that the routing protocol has its own advantages depending upon the application where it is used.
Uniform Decoration of Reduced Graphene Oxide Sheets with Gold Nanoparticles
Authors: Yang Huanping , Zhou Weiwei , Yu Bo , Wang Yingying , Cong Chunxiao , Yu Ting
Published: March 2012

A simple method employing ionic liquid functionalization is developed to achieve the uniform decoration of reduced graphene oxide sheets with gold nanoparticles. The synthesis of ionic liquid modified graphene oxide is accomplished by covalently binding 1-(3-Aminopropyl) imidazole with GO sheets. The formation mechanism of Au nanoparticles on RGO sheets is proposed to loadAuCl4-onto the surface of GO sheets through anion exchange; then reduceAuCl4-to Au NPs and at the same time reduce GO sheets to RGO sheets via a one-step process. The presence of Au NPs is well identified by SEM, TEM, and XPS. As a concept, the RGO-supported Au NPs is applied to surface-enhanced Raman spectroscopy.
Gerontechnology: Providing a Helping Hand When Caring for Cognitively Impaired Older Adults—Intermediate Results from a Controlled Study on the Satisfaction and Acceptance of Informal Caregivers
Authors: Mitseva Anelia , Peterson Carrie Beth , Karamberi Christina , Oikonomou Lamprini Ch. , Ballis Athanasios V. , Giannakakos Charalampos , Dafoulas George E.
Published: March 2012

The incidence of cognitive impairment in older age is increasing, as is the number of cognitively impaired older adults living in their own homes. Due to lack of social care resources for these adults and their desires to remain in their own homes and live as independently as possible, research shows that the current standard care provisions are inadequate. Promising opportunities exist in using home assistive technology services to foster healthy aging and to realize the unmet needs of these groups of citizens in a user-centered manner. ISISEMD project has designed, implemented, verified, and assessed an assistive technology platform of personalized home care (telecare) for the elderly with cognitive impairments and their caregivers by offering intelligent home support services. Regions from four European countries have carried out long-term pilot-controlled study in real-life conditions. This paper presents the outcomes from intermediate evaluations pertaining to user satisfaction with the system, acceptance of the technology and the services, and quality of life outcomes as a result of utilizing the services.
Extracting Fetal Electrocardiogram from Being Pregnancy Based on Nonlinear Projection
Authors: Khoa Truong Quang Dang , Tam Ho Huu Minh , Toi Vo Van
Published: March 2012

Fetal heart rate extraction from the abdominal ECG is of great importance due to the information that carries in assessing appropriately the fetus well‐being during pregnancy. In this paper, we describe a method to suppress the maternal signal and noise contamination to discover the fetal signal in a single‐lead fetal ECG recordings. We use a locally linear phase space projection technique which has been used for noise reduction in deterministically chaotic signals. Henceforth, this method is capable of extracting fetal signal even when noise and fetal component are of comparable amplitude. The result is much better if the noise is much smaller (P wave and T wave can be discovered).
Effect of Inlet Geometry on Fan Performance and Flow Field in a Half-Ducted Propeller Fan
Authors: Liu Pin , Shiomi Norimasa , Kinoue Yoichi , Jin Ying-zi , Setoguchi Toshiaki
Published: March 2012

In order to clarify the effect of rotor inlet geometry of half-ducted propeller fan on performance and velocity fields at rotor outlet, the experimental investigation was carried out using a hotwire anemometer. Three types of inlet geometry were tested. The first type is the one that the rotor blade tip is fully covered by a casing. The second is that the front one-third part of blade tip is opened and the rest is covered. The third is that the front two-thirds are opened and the rest is covered. Fan test and internal flow measurement at rotor outlet were conducted about three types of inlet geometry. At the internal flow measurement, a single slant hotwire probe was used and a periodical multisampling technique was adopted to obtain the three-dimensional velocity distributions. From the results of fan test, the pressure-rise characteristic drops at high flowrate region and the stall point shifts to high flowrate region, when the opened area of blade tip increases. From the results of velocity distributions at rotor outlet, the region with high axial velocity moves to radial inwards, the circumferential velocity near blade tip becomes high, and the flow field turns to radial outward, when the opened area increases.
Acute Renal Failure Secondary to Tuberculosis: A Diagnostic Challenge
Authors: Khilji Saeed I. , Kok Hong Kuan , Wong Limy , Dorman Anthony M. , Walshe J. Joseph
Published: March 2012

Tuberculosis is a multiorgan disease with varied clinical presentations and is reemerging due to increasing immigration and globalization. We present the case of an immigrant female patient who developed acute renal failure with clinical and biochemical features suggestive of lupus nephritis but with a timely renal biopsy showing caseating granulomata in the renal parenchyma consistent with renal tuberculosis. Despite treatment with antituberculosis treatment and resolution of TB on repeat renal biopsy, she remained haemodialysis dependent. We discuss the diagnostic challenges faced in this presentation and also explore possible differential diagnoses. This rare presentation highlights the importance of renal biopsy in the diagnosis and treatment of acute renal failure and the atypical presentation of tuberculosis.
Low‐Thrust Out‐of‐Plane Orbital Station‐Keeping Maneuvers for Satellites
Authors: Gomes Vivian M. , Prado Antonio F. B. A.
Published: March 2012

This paper considers the problem of out of plane orbital maneuvers for station keeping of satellites. The main idea is to consider that a satellite is in an orbit around the Earth and that it has its orbit is disturbed by one or more forces. Then, it is necessary to perform a small amplitude orbital correction to return the satellite to its original orbit, to keep it performing its mission. A low thrust propulsion is used to complete this task. It is important to search for solutions that minimize the fuel consumption to increase the lifetime of the satellite. To solve this problem a hybrid optimal control approach is used. The accuracy of the satisfaction of the constraints is considered, in order to try to decrease the fuel expenditure by taking advantage of this freedom. This type of problem presents numerical difficulties and it is necessary to adjust parameters, as well as details of the algorithm, to get convergence. In this versions of the algorithm that works well for planar maneuvers are usually not adequate for the out of plane orbital corrections. In order to illustrate the method, some numerical results are presented.
A Laccase with HIV-1 Reverse Transcriptase Inhibitory Activity from the Broth of Mycelial Culture of the MushroomLentinus tigrinus
Authors: Xu LiJing , Wang HeXiang , Ng TziBun
Published: March 2012

A 59 kDa laccase with inhibitory activity against HIV-1 reverse transcriptase (IC50=2.4 μM) was isolated from the broth of mycelial culture of the mushroomLentinus tigrinus. The isolation procedure involved ion exchange chromatography on DEAE-cellulose and CM-cellulose, and gel filtration by fast protein liquid chromatography on Superdex 75. The laccase was adsorbed on both types of ion exchangers. About 95-fold purification was achieved with a 25.9% yield of the enzyme. The procedure resulted in a specific enzyme activity of 76.6 U/mg. Its N-terminal amino acid sequence was GIPDLHDLTV, which showed little similarity to other mushroom laccase and otherLentinus tigrinusstrain laccase. Its characteristics were different from previously reported laccase of otherLentinus tigrinusstrain. Maximal laccase activity was observed at a pH of 4 and at a temperature of 60°C, respectively. This study yielded the information about the potentially exploitable activities ofLentinus tigrinuslaccase.