bluuebunny/crossref_metadata_2025 huggingface dataset:
Emergence of Distinct Brome Mosaic Virus Recombinants Is Determined by the Polarity of the Inoculum RNA
Authors: Kwon Sun-Jung , Rao A. L. N.
Published: February 2012

Despite overwhelming interest in the impact exerted by recombination during evolution of RNA viruses, the relative contribution of the polarity of inoculum templates remains poorly understood. Here, by agroinfiltrating
Nicotiana benthamiana
leaves, we show that brome mosaic virus (BMV) replicase is competent to initiate positive-strand [(+)-strand] synthesis on an ectopically expressed RNA3 negative strand [(−) strand] and faithfully complete the replication cycle. Consequently, we sought to examine the role of RNA polarity in BMV recombination by expressing a series of replication-defective mutants of BMV RNA3 in (+) or (−) polarity. Temporal analysis of progeny sequences revealed that the genetic makeup of the primary recombinant pool is determined by the polarity of the inoculum template. When the polarity of the inoculum template was (+), the recombinant pool that accumulated during early phases of replication was a mixture of nonhomologous recombinants. These are longer than the inoculum template length, and a nascent 3′ untranslated region (UTR) of wild-type (WT) RNA1 or RNA2 was added to the input mutant RNA3 3′ UTR due to end-to-end template switching by BMV replicase during (−)-strand synthesis. In contrast, when the polarity of the inoculum was (−), the progeny contained a pool of native-length homologous recombinants generated by template switching of BMV replicase with a nascent UTR from WT RNA1 or RNA2 during (+)-strand synthesis. Repair of a point mutation caused by polymerase error occurred only when the polarity of the inoculum template was (+). These results contribute to the explanation of the functional role of RNA polarity in recombination mediated by copy choice mechanisms.
Epigenetic Histone Modification of Epstein-Barr Virus BZLF1 Promoter during Latency and Reactivation in Raji Cells
Authors: Murata Takayuki , Kondo Yutaka , Sugimoto Atsuko , Kawashima Daisuke , Saito Shinichi , Isomura Hiroki , Kanda Teru , Tsurumi Tatsuya
Published: February 2012

The Epstein-Barr virus (EBV) predominantly establishes latent infection in B cells, and the reactivation of the virus from latency is dependent on the expression of the viral BZLF1 protein. The BZLF1 promoter (Zp) normally exhibits only low basal activity but is activated in response to chemical or biological inducers, such as 12-
O
-tetradecanoylphorbol-13-acetate (TPA), calcium ionophores, or histone deacetylase (HDAC) inhibitors. In some cell lines latently infected with EBV, an HDAC inhibitor alone can induce BZLF1 transcription, while the treatment does not enhance expression in other cell lines, such as B95-8 or Raji cells, suggesting unknown suppressive mechanisms besides histone deacetylation in those cells. Here, we found the epigenetic modification of the BZLF1 promoter in latent Raji cells by histone H3 lysine 27 trimethylation (H3K27me3), H3K9me2/me3, and H4K20me3. Levels of active markers such as histone acetylation and H3K4me3 were low in latent cells but increased upon reactivation. Treatment with 3-deazaneplanocin A (DZNep), an inhibitor of H3K27me3 and H4K20me3, significantly enhanced the BZLF1 transcription in Raji cells when in combination with an HDAC inhibitor, trichostatin A (TSA). The knockdown of Ezh2 or Suv420h1, histone methyltransferases for H3K27me3 or H4K20me3, respectively, further proved the suppression of Zp by the methylations. Taken together, the results indicate that H3K27 methylation and H4K20 methylation are involved, at least partly, in the maintenance of latency, and histone acetylation and H3K4 methylation correlate with the reactivation of the virus in Raji cells.
Vpu Augments the Initial Burst Phase of HIV-1 Propagation and Downregulates BST2 and CD4 in Humanized Mice
Authors: Sato Kei , Misawa Naoko , Fukuhara Mitsuko , Iwami Shingo , An Dong Sung , Ito Mamoru , Koyanagi Yoshio
Published: February 2012

While human cells express potent antiviral proteins as part of the host defense repertoire, viruses have evolved their own arsenal of proteins to antagonize them. BST2 was identified as an inhibitory cellular protein of HIV-1 replication, which tethers virions to the cell surface to prevent their release. On the other hand, the HIV-1 accessory protein, Vpu, has the ability to downregulate and counteract BST2. Vpu also possesses the ability to downmodulate cellular CD4 and SLAMF6 molecules expressed on infected cells. However, the role of Vpu in HIV-1 infection
in vivo
remains unclear. Here, using a human hematopoietic stem cell-transplanted humanized mouse model, we demonstrate that Vpu contributes to the efficient spread of HIV-1
in vivo
during the acute phase of infection. Although Vpu did not affect viral cytopathicity, target cell preference, and the level of viral protein expression, the amount of cell-free virions in
vpu
-deficient HIV-1-infected mice was profoundly lower than that in wild-type HIV-1-infected mice. We provide a novel insight suggesting that Vpu concomitantly downregulates BST2 and CD4, but not SLAMF6, from the surface of infected cells. Furthermore, we show evidence suggesting that BST2 and CD4 impair the production of cell-free infectious virions but do not associate with the efficiency of cell-to-cell HIV-1 transmission. Taken together, our findings suggest that Vpu downmodulates BST2 and CD4 in infected cells and augments the initial burst of HIV-1 replication
in vivo
. This is the first report demonstrating the role of Vpu in HIV-1 infection in an
in vivo
model.
Downregulation of Integrin Receptor-Signaling Genes by Epstein-Barr Virus EBNA 3C via Promoter-Proximal and -Distal Binding Elements
Authors: McClellan Michael J. , Khasnis Sarika , Wood C. David , Palermo Richard D. , Schlick Sandra N. , Kanhere Aditi S. , Jenner Richard G. , West Michelle J.
Published: February 2012

Epstein-Barr virus (EBV) establishes a persistent latent infection in B lymphocytes and is associated with the development of numerous human tumors. Epstein-Barr nuclear antigen 3C (EBNA 3C) is essential for B-cell immortalization, has potent cell cycle deregulation capabilities, and functions as a regulator of both viral- and cellular-gene expression. We performed transcription profiling on EBNA 3C-expressing B cells and identified several chemokines and members of integrin receptor-signaling pathways, including
CCL3
,
CCL4
,
CXCL10
,
CXCL11
,
ITGA4
,
ITGB1
,
ADAM28
, and
ADAMDEC1
, as cellular target genes that could be repressed by the action of EBNA 3C alone. Chemotaxis assays demonstrated that downregulation of
CXCL10
and -
11
by EBNA 3C is sufficient to reduce the migration of cells expressing the CXCL10 and -11 receptor CXCR3. Gene repression by EBNA 3C was accompanied by decreased histone H3 lysine 9/14 acetylation and increased histone H3 lysine 27 trimethylation. In an EBV-positive cell line expressing all latent genes, we identified binding sites for EBNA 3C at
ITGB1
and
ITGA4
and in a distal regulatory region between
ADAMDEC1
and
ADAM28
, providing the first demonstration of EBNA 3C association with cellular-gene control regions. Our data implicate indirect mechanisms in
CXCL10
and
CXCL11
repression by EBNA 3C. In summary, we have unveiled key cellular pathways repressed by EBNA 3C that are likely to contribute to the ability of EBV-immortalized cells to modulate immune responses, adhesion, and B-lymphocyte migration to facilitate persistence in the host.
Criminality in men with Klinefelter's syndrome and XYY syndrome: a cohort study
Authors: Stochholm Kirstine , Bojesen Anders , Jensen Anne Skakkebæk , Juul Svend , Gravholt Claus Højbjerg
Published: February 2012

Objective

To investigate the criminal pattern in men between 15 and 70 years of age diagnosed with 47,XXY (Klinefelter's syndrome (KS)) or 47,XYY compared to the general population.

Design

Register-based cohort study comparing the incidence of convictions among men with KS and with 47,XYY with age- and calendar-matched samples of the general population. Crime was classified into eight types (sexual abuse, homicide, burglary, violence, traffic, drug-related, arson and ‘others’).

Setting

Denmark 1978–2006.

Participants

All men diagnosed with KS (N=934) or 47,XYY (N=161) at risk and their age- and calendar-time-matched controls (N=88 979 and 15 356, respectively).

Results

The incidence of convictions was increased in men with KS (omitting traffic offenses) compared to controls with a HR of 1.40 (95% CI 1.23 to 1.59, p<0.001), with significant increases in sexual abuse, burglary, arson and ‘others’, but with a decreased risk of traffic and drug-related offenses. The incidence of convictions was significantly increased among men with 47,XYY compared to controls with a HR of 1.42 (95% CI 1.14 to 1.77, p<0.005) in all crime types, except drug-related crimes and traffic. Adjusting for socioeconomic variables (education, fatherhood, retirement and cohabitation) reduced the total HR for both KS and 47,XYY to levels similar to controls, while some specific crime types (sexual abuse, arson, etc) remained increased.

Conclusion

The overall risk of conviction (excluding traffic offenses) was moderately increased in men with 47,XYY or KS; however, it was similar to controls when adjusting for socioeconomic parameters. Convictions for sexual abuse, burglary, arson and ‘others’ were significantly increased. The increased risk of convictions may be partly or fully explained by the poor socioeconomic conditions related to the chromosome aberrations.
An analysis of predictive markers for intracranial haemorrhage in warfarinised head injury patients
Authors: Rendell Simon , Batchelor John S
Published: February 2012

Introduction

Minor head injury in older patients on warfarin may present in a variety of ways that often fall outside the remit of conventional guidelines. The aim of this study was to determine the relative risks for intracranial haemorrhage (ICH) in patients with subtherapeutic, therapeutic and supratherapeutic INR levels, in addition to the relative risks for the common symptoms at presentation.

Methods

The notes were retrospectively reviewed of all patients who had a CT scan requested by the emergency department over a 2-year period (January 2008 to December 2009) and from these warfarinised head injuries were identified.

Results

82 warfarinised head injury patients were identified from 3338 requested CT scans. 12 of these patients (15%) had evidence of ICH on the CT. 72 patients had their INR checked (88%) and the RR of ICH for the INR subgroups were calculated: INR <2 (RR 1.89; 95% CI 0.65 to 5.55); INR 2–3 (RR 0.84; 95% CI 0.27 to 2.64); and INR >3 (RR 0.53; 95% CI 0.13 to 2.29). The greatest proportion of those with ICH (42%) had a subtherapeutic INR. 2 out of the 12 patients (17%) were found to have intracranial bleeding despite not meeting the criteria for a CT scan according to the NICE guidelines.

Conclusion

The results of the INR subgroup analysis suggest that a subtherapeutic INR may not be protective against ICH in patients with minor head injury.
Aetiological relationships of nasal mucus cyclic nucleotides in patients with taste and smell dysfunction
Authors: Henkin Robert I , Velicu Irina
Published: February 2012

Aims

The authors previously demonstrated that nasal mucus cyclic adenosine 3′, 5′-monophosphate (cAMP) and cyclic 3′, 5′-guanosine monophosphate (cGMP) were lower in patients with smell and taste dysfunction than in normal individuals. To learn more about these differences this study related levels of nasal mucus cAMP and cGMP in patients with smell and taste dysfunction to the aetiology of their sensory loss and compared these results with those in normal individuals.

Methods

Nasal mucus cAMP and cGMP levels in patients with smell loss (hyposmia) were calculated after assembling data into aetiological groups. Levels were compared with each clinical group, with the entire patient group and with normal individuals. Data were obtained from initial values among patients with hyposmia who participated in a clinical trial of treatment with the phosphodiesterase inhibitor theophylline.

Results

Nasal mucus cyclic nucleotides in the entire patient group before treatment were below normal as previously demonstrated. Stratification by aetiology revealed differences not previously apparent. In some groups levels of cAMP and cGMP were below normal, some were similar to normal and some were above the normal mean.

Conclusions

As nasal mucus cyclic nucleotides relate to the growth and development of olfactory epithelial cells these results indicate there are differential alterations in nasal mucus cAMP and cGMP related to the aetiology of smell and taste dysfunction.
The first case record of a female patient with bubonic lymphogranuloma venereum (LGV), serovariant L2b
Authors: Verweij Stephan P , Ouburg Sander , de Vries Harry , Morré Servaas A , van Ginkel Cees J W , Bos Hanna , Sebens Fré W
Published: February 2012

Since 2003, a lymphogranuloma venereum epidemic has been reported in The Netherlands and other European countries. This epidemic is caused byChlamydia trachomatisserovariant L2b and has only been seen in men having sex with men. The authors investigated a woman presenting with a bubo in her right groin. The authors showed by real-time PCR that the woman was infected withC trachomatis, serovariant L2b. This is the first reported case study of a female patient with bubonic lymphogranuloma venereum caused by serovariant L2b, which was probably contracted via her bisexual male partner.
The Program Science initiative: improving the planning, implementation and evaluation of HIV/STI prevention programs
Authors: Aral Sevgi O , Blanchard James F
Published: February 2012

In this article, the authors describe the Program Science initiative in detail, discuss some of its recent accomplishments and explore its significance and timeliness in light of the HIV prevention challenges. The authors also describe the Program Science series being launched and present a preview of future articles.
Using recent infection testing algorithm tests in clinical practice
Authors: Carlin Elizabeth , Taha Yusri
Published: February 2012

Objectives

Recent Infection Testing Algorithm (RITA) tests are used in public health surveillance to identify the incidence of recently acquired HIV infection. This can then be used to direct public health interventions and evaluate their effects. We aimed to outline how RITA tests may be used in clinical practice with individual patients, as well as highlighting the cautions needed.

Methods

The clinical and laboratory aspects of RITA tests have been reviewed in the paper together with their clinical applications.

Results

For individuals, RITA tests can help to confirm primary HIV infection and can be useful with elements of partner notification. However, careful evaluation of the result is required and it should be considered in conjunction with the clinical history and findings.

Conclusions

There are major epidemiological and public health advantages in using RITA testing but there are also advantages to using the RITA test on an individual basis, provided that it is used appropriately.
The variation of angles between anterior and posterior carinae of tyrannosaurid teeth
Authors: Reichel Miriam
Published: February 2012

Tyrannosaurid tooth measurements have been shown to be a powerful tool for systematic analyses, as well as for studies on function and evolution of theropod dentition. In this analysis, a variable not previously addressed in depth is added to the tyrannosaurid data set. The angle between the anterior and posterior carinae can be difficult to measure consistently and a method is hereby proposed through the use of a digitizer. Five tyrannosaurid genera were analyzed: Tyrannosaurus , Tarbosaurus , Albertosaurus , Daspletosaurus , and Gorgosaurus . Only in situ data were used, and therefore some of the taxa had a limited amount of information available for this analysis. The measurements were analyzed through multivariate analyses using Paleontological Statistics (PAST), version 2.06. The analyses included principal component analyses (PCAs), discriminant analyses (DAs), and canonical variates analyses (CVAs). The results of these analyses revealed that the angle between carinae contributes significantly to the variation in the tyrannosaurid tooth data set. Additionally, this variable showed a strong correlation to tooth function (and, consequently, to tooth families), rather than tooth size. The variation observed between taxa at this stage seems insufficient for systematic purposes, however additional in situ data would help improve the effectiveness of this tool.
A Paleogene flora from the upper Bonnet Plume Formation of northeast Yukon Territory, Canada
Authors: Vavrek Matthew J. , Evans David C. , Braman Dennis R. , Campione Nicolás E. , Zazula Grant D.
Published: February 2012

Palaeontological exploration of the Bonnet Plume Basin in northwestern Yukon Territory, Canada, has revealed a Late Paleocene to Early Eocene macrofloral assemblage from a channel fill deposit. The flora is typified by cosmopolitan taxa and dominated by deciduous angiosperms, with the notable presence of Zizyphoides , Ettingshausenia , and Corylites . Floras with a similar composition are known from Late Cretaceous through Early Eocene deposits in Alaska and the Canadian Arctic Archipelago, where they have been interpreted as evidence for warm, equable temperatures. This collection represents the most diverse known Paleogene plant macrofossil assemblage from the Yukon Territory and helps to expand our knowledge of ancient high-latitude floras.
ONE-DIMENSIONAL QUANTUM WALKS WITH ONE DEFECT
Authors: CANTERO M. J. , GRÜNBAUM F. A. , MORAL L. , VELÁZQUEZ L.
Published: February 2012

The CGMV method allows for the general discussion of localization properties for the states of a one-dimensional quantum walk, both in the case of the integers and in the case of the nonnegative integers. Using this method we classify, according to such localization properties, all the quantum walks with one defect at the origin, providing explicit expressions for the asymptotic return probabilities to the origin.
A DESIGN OF PSEUDO-RANDOM BIT GENERATOR BASED ON SINGLE CHAOTIC SYSTEM
Authors: WANG XING-YUAN , XIE YI-XIN
Published: February 2012

Pseudo-random bit sequence have a wide range of applications in the field of cryptography and communications. For the good chaotic dynamical properties of chaotic systems sequence such as randomness and initial sensitivity, chaotic systems have a strong advantage in generating the pseudo-random bit sequence. However, in practical use, the dynamical properties of chaotic systems will be degraded because of the limited calculation accuracy and it even could cause a variety of security issues. To improve the security, in full analyses of the pseudo-random bit generator proposed in our former paper, we point out some problems in our former design and redesign a better pseudo-random bit generator base on it. At the same time, we make some relevant theoretical and experimental analyses on it. The experiments show that the design proposed in this paper has good statistical properties and security features.
BLACK HOLES AND ASYMPTOTICALLY SAFE GRAVITY
Authors: FALLS KEVIN , LITIM DANIEL F. , RAGHURAMAN AARTI
Published: February 2012

Quantum gravitational corrections to black holes are studied in four and higher dimensions using a renormalisation group improvement of the metric. The quantum effects are worked out in detail for asymptotically safe gravity, where the short-distance physics is characterized by a nontrivial fixed point of the gravitational coupling. We find that a weakening of gravity implies a decrease of the event horizon, and the existence of a Planck-size black hole remnant with vanishing temperature and vanishing heat capacity. The absence of curvature singularities is generic and discussed together with the conformal structure and the Penrose diagram of asymptotically safe black holes. The production cross-section of mini-black holes in energetic particle collisions, such as those at the Large Hadron Collider, is analysed within low-scale quantum gravity models. Quantum gravity corrections imply that cross-sections display a threshold, are suppressed in the Planckian, and reproduce the semiclassical result in the deep trans-Planckian region. Further implications are discussed.
WHAT THE OBLIQUE PARAMETERS S, T AND U AND THEIR EXTENSIONS REVEAL ABOUT THE 2HDM: A NUMERICAL ANALYSIS
Authors: FUNK GERHARDT , O'NEIL DEVA , WINTERS R. MICHAEL
Published: February 2012

The oblique parameters S, T and U and their higher-order extensions (V, W and X) are observables that combine electroweak precision data to quantify deviation from the Standard Model. These parameters were calculated at one loop in the basis-independent CP-violating Two-Higgs Doublet Model (2HDM). The scalar parameter space of the 2HDM was randomly sampled within limits imposed by unitarity and found to produce values of the oblique parameters within experimental bounds, with the exception of T. The experimental limits on T were used to predict information about the mass of the charged Higgs boson and the difference in mass between the charged Higgs boson and the heaviest neutral Higgs boson. In particular, it was found that the 2HDM predicts -600 GeV < mH± - m3 < 100 GeV , with values of mH± > 250 GeV being preferred. The mass scale of the new physics (M NP ) produced by random sampling was consistently fairly high, with the average of the scalar masses falling between 400 and 800 GeV for [Formula: see text], although the model can be tuned to produce a light neutral Higgs mass (~120 GeV). Hence, the values produced for V, W and X fell well within 0.01 of zero, confirming the robustness of the linear expansion approximation. Taking the CP-conserving limit of the model was found to not significantly affect the values generated for the oblique parameters.
QUANTUM D-BRANES AND EXOTIC SMOOTH ℝ4
Authors: ASSELMEYER-MALUGA TORSTEN , KRÓL JERZY
Published: February 2012

In this paper, we present the idea that the formalism of string theory is connected with the dimension 4 in a new way, not covered by phenomenological or model-building approaches. The main connection is given by structures induced by small exotic smooth ℝ4's having intrinsic meaning for physics in dimension 4. We extend the notion of stable quantum D-branes in a separable noncommutative C⋆-algebras over convolution algebras corresponding to the codimension-1 foliations of S3which are mainly connected to small exotic ℝ4. The tools of topological K-homology and K-theory as well as KK-theory describe stable quantum branes in the C⋆-algebras when naturally extended to algebras. In case of convolution algebras, small exotic smooth ℝ4's embedded in exotic ℝ4correspond to a generalized quantum brane on the algebras. These results extend the correspondence between exotic ℝ4and classical D and NS-branes from our previous work.
CURVATURE PROPERTIES OF PSEUDO-SPHERE BUNDLES OVER PARAQUATERNIONIC MANIFOLDS
Authors: VÎLCU GABRIEL EDUARD , VOICU RODICA CRISTINA
Published: February 2012

In this paper we obtain several curvature properties of the twistor and reflector spaces of a paraquaternionic Kähler manifold and prove the existence of both positive and negative mixed 3-Sasakian structures in a principal SO (2, 1)-bundle over a paraquaternionic Kähler manifold.
Effects of insulin on Na and K transporters in the rat CCD
Authors: Frindt Gustavo , Palmer Lawrence G.
Published: February 2012

We tested the effects of insulin (2 nM, 30–60 min) on principal cells of isolated split-open rat cortical collecting ducts (CCD) using whole-cell current measurements. Insulin addition to the superfusate of the tubules enhanced Na pump (ouabain-sensitive) current from 18 ± 3 to 31 ± 3 pA/cell in control and from 74 ± 9 to 126 ± 11 pA/cell in high K-fed animals. It also more than doubled ROMK (tertiapin-Q-sensitive) K+currents in control CCD from 320 ± 40 to 700 ± 80 pA/cell, although it did not affect this current in tubules from K-loaded rats. Insulin did not induce the appearance of amiloride-sensitive Na+current in control animals, while in high K-fed animals the currents were similar in the presence (140 ± 30) and the absence (180 ± 70 pA/cell) of insulin. Intraperitoneal injection of insulin plus hypertonic dextrose decreased Na excretion, as previously reported. However, injection of dextrose alone, or the nonmetabolized sugar mannose, had similar effects, suggesting that they were largely the result of vascular volume depletion rather than specific actions of the hormone. In summary, we find no evidence for acute upregulation of the epithelial Na channel (ENaC) by physiological concentrations of insulin in the mammalian CCD. However, the hormone does activate both the Na/K pump and apical K+channels and could, under some conditions, enhance renal K+secretion.
Distinct developmental profiles in typical speech acquisition
Authors: Vick Jennell C. , Campbell Thomas F. , Shriberg Lawrence D. , Green Jordan R. , Abdi Hervé , Rusiewicz Heather Leavy , Venkatesh Lakshmi , Moore Christopher A.
Published: February 2012

Three- to five-year-old children produce speech that is characterized by a high level of variability within and across individuals. This variability, which is manifest in speech movements, acoustics, and overt behaviors, can be input to subgroup discovery methods to identify cohesive subgroups of speakers or to reveal distinct developmental pathways or profiles. This investigation characterized three distinct groups of typically developing children and provided normative benchmarks for speech development. These speech development profiles, identified among 63 typically developing preschool-aged speakers (ages 36–59 mo), were derived from the children's performance on multiple measures. These profiles were obtained by submitting to a k-means cluster analysis of 72 measures that composed three levels of speech analysis: behavioral (e.g., task accuracy, percentage of consonants correct), acoustic (e.g., syllable duration, syllable stress), and kinematic (e.g., variability of movements of the upper lip, lower lip, and jaw). Two of the discovered group profiles were distinguished by measures of variability but not by phonemic accuracy; the third group of children was characterized by their relatively low phonemic accuracy but not by an increase in measures of variability. Analyses revealed that of the original 72 measures, 8 key measures were sufficient to best distinguish the 3 profile groups.
Impaired crossed facilitation of the corticospinal pathway after cervical spinal cord injury
Authors: Bunday Karen L. , Perez Monica A.
Published: February 2012

In uninjured humans, it is well established that voluntary contraction of muscles on one side of the body can facilitate transmission in the contralateral corticospinal pathway. This crossed facilitatory effect may favor interlimb coordination and motor performance. Whether this aspect of corticospinal function is preserved after chronic spinal cord injury (SCI) is unknown. Here, using transcranial magnetic stimulation, we show in patients with chronic cervical SCI (C5–C8) that the size of motor evoked potentials (MEPs) in a resting intrinsic hand muscle remained unchanged during increasing levels of voluntary contraction with a contralateral distal or proximal arm muscle. In contrast, MEP size in a resting hand muscle was increased during the same motor tasks in healthy control subjects. The magnitude of voluntary electromyography was negatively correlated with MEP size after chronic cervical SCI and positively correlated in healthy control subjects. To examine the mechanisms contributing to MEP crossed facilitation we examined short-interval intracortical inhibition (SICI), interhemispheric inhibition (IHI), and motoneuronal behavior by testing F waves and cervicomedullary MEPs (CMEPs). During strong voluntary contractions SICI was unchanged after cervical SCI and decreased in healthy control subjects compared with rest. F-wave amplitude and persistence and CMEP size remained unchanged after cervical SCI and increased in healthy control subjects compared with rest. In addition, during strong voluntary contractions IHI was unchanged in cervical SCI compared with rest. Our results indicate that GABAergic intracortical circuits, interhemispheric glutamatergic projections between motor cortices, and excitability of index finger motoneurons are neural mechanisms underlying, at least in part, the lack of crossed corticospinal facilitation observed after SCI. Our data point to the spinal motoneurons as a critical site for modulating corticospinal transmission after chronic cervical SCI.
Electrical stimulation of retinal neurons in epiretinal and subretinal configuration using a multicapacitor array
Authors: Eickenscheidt Max , Jenkner Martin , Thewes Roland , Fromherz Peter , Zeck Günther
Published: February 2012

Electrical stimulation of retinal neurons offers the possibility of partial restoration of visual function. Challenges in neuroprosthetic applications are the long-term stability of the metal-based devices and the physiological activation of retinal circuitry. In this study, we demonstrate electrical stimulation of different classes of retinal neurons with a multicapacitor array. The array—insulated by an inert oxide—allows for safe stimulation with monophasic anodal or cathodal current pulses of low amplitude. Ex vivo rabbit retinas were interfaced in either epiretinal or subretinal configuration to the multicapacitor array. The evoked activity was recorded from ganglion cells that respond to light increments by an extracellular tungsten electrode. First, a monophasic epiretinal cathodal or a subretinal anodal current pulse evokes a complex burst of action potentials in ganglion cells. The first action potential occurs within 1 ms and is attributed to direct stimulation. Within the next milliseconds additional spikes are evoked through bipolar cell or photoreceptor depolarization, as confirmed by pharmacological blockers. Second, monophasic epiretinal anodal or subretinal cathodal currents elicit spikes in ganglion cells by hyperpolarization of photoreceptor terminals. These stimuli mimic the photoreceptor response to light increments. Third, the stimulation symmetry between current polarities (anodal/cathodal) and retina-array configuration (epi/sub) is confirmed in an experiment in which stimuli presented at different positions reveal the center-surround organization of the ganglion cell. A simple biophysical model that relies on voltage changes of cell terminals in the transretinal electric field above the stimulation capacitor explains our results. This study provides a comprehensive guide for efficient stimulation of different retinal neuronal classes with low-amplitude capacitive currents.
Myco-Biocontrol of Insect Pests: Factors Involved, Mechanism, and Regulation
Authors: Sandhu Sardul Singh , Sharma Anil K. , Beniwal Vikas , Goel Gunjan , Batra Priya , Kumar Anil , Jaglan Sundeep , Sharma A. K. , Malhotra Sonal
Published: February 2012

The growing demand for reducing chemical inputs in agriculture and increased resistance to insecticides have provided great impetus to the development of alternative forms of insect-pest control. Myco-biocontrol offers an attractive alternative to the use of chemical pesticides. Myco-biocontrol agents are naturally occurring organisms which are perceived as less damaging to the environment. Their mode of action appears little complex which makes it highly unlikely that resistance could be developed to a biopesticide. Past research has shown some promise of the use of fungi as a selective pesticide. The current paper updates us about the recent progress in the field of myco-biocontrol of insect pests and their possible mechanism of action to further enhance our understanding about the biological control of insect pests.
The Role of Pathogenesis-Related Proteins in the Tomato-Rhizoctonia solani Interaction
Authors: Taheri Parissa , Tarighi Saeed
Published: February 2012

Rhizoctonia solani is one of the most destructive pathogens causing foot rot disease on tomato. In this study, the molecular and cellular changes of a partially resistant (Sunny 6066) and a susceptible (Rio Grande) tomato cultivar after infection with necrotrophic soil-borne fungus R. solani were compared. The expression of defense-related genes such as chitinase (LOC544149) and peroxidase (CEVI-1) in infected tomato cultivars was investigated using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). This method revealed elevated levels of expression for both genes in the partially resistant cultivar compared to the susceptible cultivar. One of the most prominent facets of basal plant defense responses is the formation of physical barriers at sites of attempted fungal penetration. These structures are produced around the sites of potential pathogen ingress to prevent pathogen progress in plant tissues. We investigated formation of lignin, as one of the most important structural barriers affecting plant resistance, using thioglycolic acid assay. A correlation was found between lignification and higher level of resistance in Sunny 6066 compared to Rio Grande cultivar. These findings suggest the involvement of chitinase, peroxidase, and lignin formation in defense responses of tomato plants against R. solani as a destructive pathogen.
Molecular Mechanisms of Preeclampsia
Authors: Vitoratos N. , Hassiakos D. , Iavazzo C.
Published: February 2012

Preeclampsia is one of the leading causes of maternal morbidity/mortality. The pathogenesis of preeclampsia is still under investigation. The aim of this paper is to present the molecular mechanisms implicating in the pathway leading to preeclampsia.
Risk of Orthopedic Surgical Site Infections in Patients with Rheumatoid Arthritis Treated with Antitumor Necrosis Factor Alfa Therapy
Authors: da Cunha Bernardo Matos , Maria Henrique da Mota Licia , dos Santos-Neto Leopoldo Luiz
Published: February 2012

Introduction. International guidelines recommend interruption of anti-TNF medications in the perioperative period, but there are no randomized trials to support such recommendation.Objectives. To study literature evidence assessing the risk of surgical site infections in orthopedic surgery patients with RA using anti-TNF drugs, compared to untreated patients or those using conventional DMARD.Methods. Systematic review of cohort studies is concerning surgical site infections in orthopedic procedures in patients with RA.Results. Three studies were selected. Only one was considered of high-quality, albeit with low statistical power. The review resulted in inconclusive data, since the best quality study showed no significant differences between groups, while others showed increased risk of infections in patients using anti-TNF medications.Conclusion. It is unclear whether patients with RA using anti-TNF medications are at increased risk of surgical site infections. Randomized controlled trials or new high quality observational studies are needed to clarify the issue.
Test Gas Generation from Pure Liquids: An Application-Oriented Overview of Methods in a Nutshell
Authors: Li Yue , Täffner Tim , Bischoff Michael , Niemeyer Bernd
Published: February 2012

The generation of test gas from pure liquids has a wide variety of applications in laboratory and field experiments, for which the quality of the test gas is of significance. Therefore, various methods for test gas generation have been designed. Each method has unique advantages and disadvantages. Thus, a short overview is presented within the scope of this paper. Furthermore, a common bubbler system is presented, which was built to generate test gas from volatile organic compounds for experimental usage in laboratory applications. An analysis is conducted with respect to the generated concentrations at different temperatures and flow rates of the diluting gas. Accuracy and stability of this method are investigated.
Interaction between Chronic Inflammation and Oral HPV Infection in the Etiology of Head and Neck Cancers
Authors: Tezal Mine
Published: February 2012

Incidences of oral tongue, base of the tongue, and tonsil cancers have been increasing steadily in many parts of the world in spite of declining rates of tobacco use over the last four decades. A better understanding of the etiology, interactions between risk factors, and new approaches to prevention and treatment are necessary to change this course. This paper will present evidence supporting a potential role of chronic inflammation in the etiologies of oral human papillomavirus infection and head and neck squamous cell carcinoma, and it will discuss the implications for prevention and treatment.
Synthesis of Poly(Ortho‐Phenylenediamine) Fluffy Microspheres and Application for the Removal of Cr(VI)
Authors: Wang Zhoufeng , Liao Fang
Published: February 2012

We reported the synthesis of fluffy poly(o‐phenylenediamine) (PoPD) microspheres via chemical polymerization of oPD monomers by ammonium persulfate (APS) at room temperature. The SEM images showed that PoPD microspheres with an average diameter of 1.5 μm and their surfaces consist of highly oriented nanofibers. Furthermore, PoPD microspheres were used as adsorbent materials for the removal of Cr(VI) from aqueous solutions. The Cr(VI) adsorption behavior on the prepared PoPD microspheres was studied at different adsorption contact times, solution pH values, and amount of the adsorbent. Experimental isotherms of Cr(VI) ions were successfully fit to the Langmuir isotherm model. The results indicate that the PoPD fluffy microspheres are an effective adsorbent for the removal of Cr(VI) ions from aqueous solutions, and they could be useful in treatment of Cr(VI)‐polluted wastewaters.
A Novel Fractional‐Discrete‐Cosine‐Transform‐Based Reversible Watermarking for Healthcare Information Management Systems
Authors: Ko Lu-Ting , Chen Jwu-E , Shieh Yaw-Shih , Scalia Massimo , Sung Tze-Yun
Published: February 2012

Digital watermarking is a good tool for healthcare information management systems. The well‐known quantization‐index‐modulation‐ (QIM‐) based watermarking has its limitations as the host image will be destroyed; however, the recovery of medical image is essential to avoid misdiagnosis. A transparent yet reversible watermarking algorithm is required for medical image applications. In this paper, we propose a fractional‐discrete‐cosine‐transform‐ (FDCT‐) based watermarking to exactly reconstruct the host image. Experimental results show that the FDCT‐based watermarking is preferable to the QIM‐based watermarking for the medical image applications.
GABA Metabolism and Transport: Effects on Synaptic Efficacy
Authors: Roth Fabian C. , Draguhn Andreas
Published: February 2012

GABAergic inhibition is an important regulator of excitability in neuronal networks. In addition, inhibitory synaptic signals contribute crucially to the organization of spatiotemporal patterns of network activity, especially during coherent oscillations. In order to maintain stable network states, the release of GABA by interneurons must be plastic in timing and amount. This homeostatic regulation is achieved by several pre- and postsynaptic mechanisms and is triggered by various activity-dependent local signals such as excitatory input or ambient levels of neurotransmitters. Here, we review findings on the availability of GABA for release at presynaptic terminals of interneurons. Presynaptic GABA content seems to be an important determinant of inhibitory efficacy and can be differentially regulated by changing synthesis, transport, and degradation of GABA or related molecules. We will discuss the functional impact of such regulations on neuronal network patterns and, finally, point towards pharmacological approaches targeting these processes.
A Distributed Algorithm for Virtual Backbone Construction with Cellular Structure in WSNs
Authors: Xiang Yu , Liu Xiaojuan , Tang Yong , Xiao Juncong , Zhang Jun
Published: February 2012

The normal node in wireless sensor networks (WSNs) often has no constant energy supply. To make efficient use of limited energy resources significant, a major way to save limited energy resources is constructing a smaller virtual backbone in WSNs. In this paper, we propose a distributed algorithm for virtual backbone construction with cellular structure in WSNs (DBC), which is an improvement of algorithm ABP (Duresi and Paruchuri, 2008) and minimize the distortion of constructed cellular structure by improving the way of calculating strategic points using 1-hop neighbor information. Our simulation results show that algorithm DBC has smaller virtual backbone than algorithm ABP, and the number of backbone nodes is much fewer than that one.
Pattern and Determinants of Antiretroviral Drug Adherence among Nigerian Pregnant Women
Authors: Ekama S. O. , Herbertson E. C. , Addeh E. J. , Gab-Okafor C. V. , Onwujekwe D. I. , Tayo F. , Ezechi O. C.
Published: February 2012

Background. The need for a high level of adherence to antiretroviral drugs has remained a major hurdle to achieving maximal benefit from its use in pregnancy. This study was designed to determine the level of adherence and identify factors that influence adherence during pregnancy.Method. This is a cross-sectional study utilizing a semistructured questionnaire. Bivariate and multiple logistic regression models were used to determine factors independently associated with good drug adherence during pregnancy.Result. 137 (80.6%) of the interviewed 170 women achieved adherence level of ≥95% using 3 day recall. The desire to protect the unborn child was the greatest motivation (51.8%) for good adherence. Fear of being identified as HIV positive (63.6%) was the most common reason for nonadherence. Marital status, disclosure of HIV status, good knowledge of ART, and having a treatment supporter were found to be significantly associated with good adherence at bivariate analysis. However, after controlling for confounders, only HIV status disclosure and having a treatment partner retained their association with good adherence.Conclusion. Disclosure of HIV status and having treatment support are associated with good adherence. Maternal desire to protect the child was the greatest motivator for adherence.
Expression of CD44v6 and Its Association with Prognosis in Epithelial Ovarian Carcinomas
Authors: Zhou Dang-xia , Liu Yun-xia , Xue Ya-hong
Published: February 2012

The aim of this study was to evaluate CD44v6 protein expression and its prognostic value of CD44v6 in ovarian carcinoma. The expression of CD44v6 was analyzed in 62 patients with ovarian carcinoma by immunohistochemical method. The data obtained were analyzed by univariate and multivariate analyses. The present study clearly demonstrates that tumor tissues from 41 (66.1%) patients showed positive expression with CD44v6. The expression of CD44v6 was significantly correlated with histological type, FIGO stage and histological grade of ovarian carcinomas. Concerning the prognosis, the survival period of patients with CD44v6 positive was shorter than that of patients with CD44v6 negative (36.6% versus 66.7%, 5-year survival, P<0.05). Univariate analysis showed that CD44v6 expression, histological type, FIGO stage and histological grade were associated with 5-year survival, and CD44v6 expression was associated with histological type, FIGO stage and histological grade and 5-year survival. In multivariate analysis, using the COX-regression model, CD44v6 expression was important prognostic factor. In conclusion, these results suggest that CD44v6 may be related to histological type, FIGO stage and histological grade of ovarian carcinomas, and CD44v6 may be an important molecular marker for poor prognosis in ovarian carcinomas.
A 10-Year Experience in Intraoperative Parathyroid Hormone Measurements for Primary Hyperparathyroidism: A Prospective Study of 91 Previous Unexplored Patients
Authors: Neves M. C. , Ohe M. N. , Rosano M. , Abrahão M. , Cervantes O. , Lazaretti-Castro M. , Vieira J. G. H. , Kunii I. S. , Santos R. O.
Published: February 2012

Introduction. Primary hyperparathyroidism (PHP) is characteristically determined by high levels of calcium and high or inappropriate levels of parathyroid hormone (PTH). Technological advances have dramatically changed the surgical technique over the years once intraoperative parathyroid hormone (IOPTH) assay had allowed for focused approaches.Objective. To evaluate our 10-year experience in employing a rapid intraoperative PTH assay for PHP.Methods. A prospective cohort of 91 PHP-operated patients in a tertiary institution in São Paulo, Brazil, from June 2000 to April 2011.Results. We had 85 (93.4%) successful parathyroidectomies, 6 (6.6%) failed parathyroidectomies in 91 previous unexplored patients, and 5 (100%) successful remedial surgeries. The IOPTH was true-positive in 88.5%, true-negative in 7.3%, false-positive in 2.1%, and false-negative in 2.1% of the procedures. IOPTH was able to obviate additional exploration or to ask for additional exploration in 92 (95.8%) procedures.Conclusion. The IOPTH revealed to be an important technological adjunct in the current parathyroid surgery for PHP.
Adolescents, Graduated Autonomy, and Genetic Testing
Authors: Fox Susan
Published: February 2012

Autonomy takes many shapes. The concept of “graduated autonomy” is conceived as comprising several unique features: (1) it is incremental, (2) it is proportional, and (3) it is related to thetelosof the life stage during which it occurs. This paper focuses on graduated autonomy in the context of genetic testing during adolescence. Questions can be raised about other life stages as well, and some of these questions will be addressed by discussing a possible fourth characteristic of graduated autonomy, that is, its elasticity. Further scholarship and analysis is needed to refine the concept of graduated autonomy and examine its applications.
Prognostic Role of PIK3CA Mutation in Colorectal Cancer: Cohort Study and Literature Review
Authors: Liao Xiaoyun , Morikawa Teppei , Lochhead Paul , Imamura Yu , Kuchiba Aya , Yamauchi Mai , Nosho Katsuhiko , Qian Zhi Rong , Nishihara Reiko , Meyerhardt Jeffrey A. , Fuchs Charles S. , Ogino Shuji
Published: February 2012

Purpose: Mutations in PIK3CA [the gene encoding the p110α catalytic subunit of phosphatidylinositide-3-kinase (PI3K)] play an important role in colorectal carcinogenesis. Experimental evidence suggests that PIK3CA exon 9 and exon 20 mutations trigger different biologic effects, and that concomitant mutations in both exons 9 and 20 synergistically enhance tumorigenic effects. Thus, we hypothesized that PIK3CA exon 9 and exon 20 mutations might have differential effects on clinical outcome in colorectal cancer, and that concomitant PIK3CA exon 9 and 20 mutations might confer aggressive tumor behavior.

Experimental Design: We sequenced PIK3CA by pyrosequencing in 1,170 rectal and colon cancers in two prospective cohort studies, and found 189 (16%) PIK3CA mutated tumors. Mortality HR according to PIK3CA status was computed using Cox proportional hazards model, adjusting for clinical and molecular features, including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation, and BRAF and KRAS mutations.

Results: Compared with PIK3CA wild-type cases, patients with concomitant PIK3CA mutations in exons 9 and 20 experienced significantly worse cancer-specific survival [log-rank P = 0.031; multivariate HR = 3.51; 95% confidence interval (CI): 1.28–9.62] and overall survival (log-rank P = 0.0008; multivariate HR = 2.68; 95% CI: 1.24–5.77). PIK3CA mutation in either exon 9 or 20 alone was not significantly associated with patient survival. No significant interaction of PIK3CA mutation with BRAF or KRAS mutation was observed in survival analysis.

Conclusion: Coexistence of PIK3CA (the PI3K p110α subunit) exon 9 and 20 mutations, but not PIK3CA mutation in either exon 9 or 20 alone, is associated with poor prognosis of colorectal cancer patients. Clin Cancer Res; 18(8); 2257–68. ©2012 AACR.