bluuebunny/crossref_metadata_2025 huggingface dataset:
Poly(ADP-Ribose) Polymerase 1 Promotes Transcriptional Repression of Integrated Retroviruses
Authors: Bueno Murilo T. D. , Reyes Daniel , Valdes Luis , Saheba Adarsh , Urias Eduardo , Mendoza Crystal , Fregoso Oliver I. , Llano Manuel
Published: December 2012

Poly(ADP-ribose) polymerase 1 (PARP-1) is a cellular enzyme with a fundamental role in DNA repair and the regulation of chromatin structure, processes involved in the cellular response to retroviral DNA integration. However, the function of PARP-1 in retroviral DNA integration is controversial, probably due to the functional redundancy of the PARP family in mammalian cells. We evaluated the function of PARP-1 in retroviral infection using the chicken B lymphoblastoid cell line DT40. These cells lack significant PARP-1 functional redundancy and efficiently support the postentry early events of the mammalian-retrovirus replication cycle. We observed that DT40 PARP-1
−/−
cells were 9- and 6-fold more susceptible to infection by human immunodeficiency virus type 1 (HIV-1)- and murine leukemia virus (MLV)-derived viral vectors, respectively, than cells expressing PARP-1. Production of avian Rous-associated virus type 1 was also impaired by PARP-1. However, the susceptibilities of these cell lines to infection by the nonretrovirus vesicular stomatitis virus were indistinguishable. Real-time PCR analysis of the HIV-1 life cycle demonstrated that PARP-1 did not impair reverse transcription, nuclear import of the preintegration complex, or viral DNA integration, suggesting that PARP-1 regulates a postintegration step. In support of this hypothesis, pharmacological inhibition of the epigenetic mechanism of transcriptional silencing increased retroviral expression in PARP-1-expressing cells, suppressing the differences observed. Further analysis of the implicated molecular mechanism indicated that PARP-1-mediated retroviral silencing requires the C-terminal region, but not the enzymatic activity, of the protein. In sum, our data indicate a novel role of PARP-1 in the transcriptional repression of integrated retroviruses.
Recruitment and Retention of B Cells in the Central Nervous System in Response to Alphavirus Encephalomyelitis
Authors: Metcalf Talibah U. , Baxter Victoria K. , Nilaratanakul Voraphoj , Griffin Diane E.
Published: December 2012

Sindbis virus (SINV) infection of neurons results in nonfatal viral encephalomyelitis and provides a model system for understanding recovery from virus infection of the central nervous system (CNS). Infection is followed by clearance of infectious virus, a gradual decrease in viral RNA, and then long-term maintenance of low levels of viral RNA. Antibody to the E2 glycoprotein is important for virus clearance, and B cells enter the CNS along with CD4+and CD8+T cells during the early clearance phase. Antibody-secreting cells (ASCs) are present in the CNS and become enriched for SINV-specific ASCs. We have evaluated the factors within the CNS that facilitate continued local antibody production after infection. Expression of CXCL9, CXCL10, CCL1, CCL2, and CCL5 chemokine mRNAs increased early, and infiltrating B cells expressed CXCR3, CXCR5, and CCR7. The mRNAs for IL-10 and IL-21, cytokines important for B cell proliferation and differentiation, rose rapidly and remained elevated long after clearance of infectious virus. Active proliferation of B cells, as indicated by Ki-67 expression, continued for months. Bromodeoxyuridine (BrdU) labeling of proliferating cells showed that ASCs produced in the draining cervical lymph nodes during the early germinal center response were preferentially retained in the CNS. Sustained increase in B-cell-activating factor (BAFF) mRNA in the CNS and BAFF receptor expression by B cells coincided with the long-term maintenance of SINV-specific ASCs in the brain. We conclude that multiple changes in the brain microenvironment facilitate B-cell entry and support proliferation and differentiation and long-term survival of antiviral ASCs during recovery from alphaviral encephalomyelitis.
Evidence for a Different Susceptibility of Primate Lentiviruses to Type I Interferons
Authors: Cordeil Stéphanie , Nguyen Xuan-Nhi , Berger Gregory , Durand Stéphanie , Ainouze Michelle , Cimarelli Andrea
Published: December 2012

Type I interferons induce a complex transcriptional program that leads to a generalized antiviral response against a large panel of viruses, including human immunodeficiency virus type 1 (HIV-1). However, despite the fact that interferons negatively regulate HIV-1ex vivo, a chronic interferon state is linked to the progression of AIDS and to robust viral replication, rather than protection,in vivo. To explain this apparent contradiction, we hypothesized that HIV-1 may have evolved a partial resistance to interferon, and to test this hypothesis, we analyzed the effects of alpha interferon (IFN-α) on the infectivity of HIV-1, human immunodeficiency virus type 2 (HIV-2), and rhesus monkey simian immunodeficiency virus (SIVmac). The results we obtained indicate that HIV-1 is more resistant to an IFN-α-induced response than are HIV-2 and SIVmac. Our data indicate that the accumulation of viral DNA is more compromised following the infection of IFN-α-treated cells with HIV-2 and SIVmac than with HIV-1. This defect correlates with a faster destabilization of HIV-2 viral nucleoprotein complexes (VNCs), suggesting a link between VNC destabilization and impaired viral DNA (vDNA) accumulation. The differential susceptibilities to IFN-α of the primate lentiviruses tested here do not map to the capsid protein (CA), excludingde factoa role for human tripartite motif protein isoform 5 alpha (Trim5α) in this restriction; this also suggests that an additional restriction mechanism differentially affects primate lentivirus infection. The different behaviors of HIV-1 and HIV-2 with respect to IFN-α responses may account at least in part for the differences in pathogenesis observed between these two virus types.
Mutant Fusion Proteins with Enhanced Fusion Activity Promote Measles Virus Spread in Human Neuronal Cells and Brains of Suckling Hamsters
Authors: Watanabe Shumpei , Shirogane Yuta , Suzuki Satoshi O. , Ikegame Satoshi , Koga Ritsuko , Yanagi Yusuke
Published: December 2012

Subacute sclerosing panencephalitis (SSPE) is a fatal degenerative disease caused by persistent measles virus (MV) infection in the central nervous system (CNS). From the genetic study of MV isolates obtained from SSPE patients, it is thought that defects of the matrix (M) protein play a crucial role in MV pathogenicity in the CNS. In this study, we report several notable mutations in the extracellular domain of the MV fusion (F) protein, including those found in multiple SSPE strains. The F proteins with these mutations induced syncytium formation in cells lacking SLAM and nectin 4 (receptors used by wild-type MV), including human neuronal cell lines, when expressed together with the attachment protein hemagglutinin. Moreover, recombinant viruses with these mutations exhibited neurovirulence in suckling hamsters, unlike the parental wild-type MV, and the mortality correlated with their fusion activity. In contrast, the recombinant MV lacking the M protein did not induce syncytia in cells lacking SLAM and nectin 4, although it formed larger syncytia in cells with either of the receptors. Since human neuronal cells are mainly SLAM and nectin 4 negative, fusion-enhancing mutations in the extracellular domain of the F protein may greatly contribute to MV spread via cell-to-cell fusion in the CNS, regardless of defects of the M protein.
Early Adaptive Immune Responses in the Respiratory Tract of Foot-and-Mouth Disease Virus-Infected Cattle
Authors: Pega J. , Bucafusco D. , Di Giacomo S. , Schammas J. M. , Malacari D. , Capozzo A. V. , Arzt J. , Pérez-Beascoechea C. , Maradei E. , Rodríguez L. L. , Borca M. V. , Pérez-Filgueira M.
Published: December 2012

Foot-and-mouth disease (FMD) is a highly contagious viral disease which affects both domestic and wild biungulate species. This acute disease, caused by the FMD virus (FMDV), usually includes an active replication phase in the respiratory tract for up to 72 h postinfection, followed by hematogenous dissemination and vesicular lesions at oral and foot epithelia. The role of the early local adaptive immunity of the host in the outcome of the infection is not well understood. Here we report the kinetics of appearance of FMDV-specific antibody-secreting cells (ASC) in lymphoid organs along the respiratory tract and the spleen in cattle infected by aerosol exposure. While no responses were observed for up to 3 days postinfection (dpi), all animals developed FMDV-ASC in all the lymphoid organs studied at 4 dpi. Tracheobronchial lymph nodes were the most reactive organs at this time, and IgM was the predominant isotype, followed by IgG1. Numbers of FMDV-ASC were further augmented at 5 and 6 dpi, with an increasing prevalence in upper respiratory organs. Systemic antibody responses were slightly delayed compared with the local reaction. Also, IgM was the dominant isotype in serum at 5 dpi, coinciding with a sharp decrease of viral RNA detection in peripheral blood. These results indicate that following aerogenous administration, cattle develop a rapid and vigorous genuine local antibody response throughout the respiratory tract. Time course and isotype profiles indicate the presence of an efficient T cell-independent antibody response which drives the IgM-mediated virus clearance in cattle infected by FMDV aerosol exposure.
The PA-Gene-Mediated Lethal Dissemination and Excessive Innate Immune Response Contribute to the High Virulence of H5N1 Avian Influenza Virus in Mice
Authors: Hu Jiao , Hu Zenglei , Song Qingqing , Gu Min , Liu Xiaowen , Wang Xiaoquan , Hu Shunlin , Chen Chaoyang , Liu Huimou , Liu Wenbo , Chen Sujuan , Peng Daxin , Liu Xiufan
Published: December 2012

Highly pathogenic H5N1 influenza A virus remains a substantial threat to public health. To understand the molecular basis and host mechanism for the high virulence of H5N1 viruses in mammals, we compared two H5N1 isolates which have similar genetic backgrounds but greatly differ in their virulence in mice. A/Chicken/Jiangsu/k0402/2010 (CK10) is highly pathogenic, whereas A/Goose/Jiangsu/k0403/2010 (GS10) is nonpathogenic. We first showed that CK10 elicited a more potent innate immune response than did GS10 in mouse lungs by increasing the number and expression levels of activated genes. We then generated a series of reassortants between the two viruses and evaluated their virulence in mice. Inclusion of the CK10 PA gene in the GS10 background resulted in a dramatic increase in virulence. Conversely, expression of the GS10 PA gene in the CK10 background significantly attenuated the virulence. These results demonstrated that the PA gene mainly determines the pathogenicity discrepancy between CK10 and GS10 in mice. We further determined that arginine (R) at position 353 of the PA gene contributes to the high virulence of CK10 in mice. The reciprocal substitution at position 353 in PA or the exchange of the entire PA gene largely caused the transfer of viral phenotypes, including virus replication, polymerase activity, and manipulation of the innate response, between CK10 and GS10. We therefore defined a novel molecular marker associated with the high virulence of H5N1 influenza viruses, providing further insights into the pathogenesis of H5N1 viruses in mammals.
Nectin-4-Dependent Measles Virus Spread to the Cynomolgus Monkey Tracheal Epithelium: Role of Infected Immune Cells Infiltrating the Lamina Propria
Authors: Frenzke Marie , Sawatsky Bevan , Wong Xiao X. , Delpeut Sébastien , Mateo Mathieu , Cattaneo Roberto , von Messling Veronika
Published: December 2012

After the contagion measles virus (MV) crosses the respiratory epithelium within myeloid cells that express the primary receptor signaling lymphocytic activation molecule (SLAM), it replicates briskly in SLAM-expressing cells in lymphatic organs. Later, the infection spreads to epithelia expressing nectin-4, an adherens junction protein expressed preferentially in the trachea, but how it gets there is not understood. To characterize the mechanisms of spread, we infected groups of 5 or 6 cynomolgus monkeys (
Macaca fascicularis
) with either a wild-type MV or its “N4-blind” derivative, which is unable to enter nectin-4-expressing cells because of the targeted mutation of two hemagglutinin residues. As expected, both viruses caused similar levels of immunosuppression, as monitored by reductions in white blood cell counts and lymphocyte proliferation activity. However, monkeys infected with the N4-blind MV cleared infection more rapidly. Wild-type virus-infected monkeys secreted virus, while marginal virus titers were detected in tracheal lavage fluid cells of N4-blind MV-infected hosts. Analyses of tracheal rings obtained at necropsy (day 12) documented widespread infection of individual cells or small cell clusters in the subepithelial lamina propria of monkeys infected with either virus. However, only wild-type MV spread to the epithelium, forming numerous infectious centers comprised of many contiguous columnar cells. Infected CD11c
+
myeloid (macrophage or dendritic) cells were frequently observed in the lamina propria below epithelial infectious centers. Thus, MV may use myeloid cells as vehicles not only immediately after contagion but also to infect epithelia of tissues expressing nectin-4, including the trachea.
Prion Propagation and Toxicity Occur
In Vitro
with Two-Phase Kinetics Specific to Strain and Neuronal Type
Authors: Hannaoui Samia , Maatouk Layal , Privat Nicolas , Levavasseur Etienne , Faucheux Baptiste A. , Haïk Stéphane
Published: December 2012

Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative disorders that occur in humans and animals. The neuropathological hallmarks of TSEs are spongiosis, glial proliferation, and neuronal loss. The only known specific molecular marker of TSEs is the abnormal isoform (PrP
Sc
) of the host-encoded prion protein (PrP
C
), which accumulates in the brain of infected subjects and forms infectious prion particles. Although this transmissible agent lacks a specific nucleic acid component, several prion strains have been isolated. Prion strains are characterized by differences in disease outcome, PrP
Sc
distribution patterns, and brain lesion profiles at the terminal stage of the disease. The molecular factors and cellular mechanisms involved in strain-specific neuronal tropism and toxicity remain largely unknown. Currently, no cellular model exists to facilitate
in vitro
studies of these processes. A few cultured cell lines that maintain persistent scrapie infections have been developed, but only two of them have shown the cytotoxic effects associated with prion propagation. In this study, we have developed primary neuronal cultures to assess
in vitro
neuronal tropism and toxicity of different prion strains (scrapie strains 139A, ME7, and 22L). We have tested primary neuronal cultures enriched in cerebellar granular, striatal, or cortical neurons. Our results showed that (i) a strain-specific neuronal tropism operated
in vitro
; (ii) the cytotoxic effect varied among strains and neuronal cell types; (iii) prion propagation and toxicity occurred in two kinetic phases, a replicative phase followed by a toxic phase; and (iv) neurotoxicity peaked when abnormal PrP accumulation reached a plateau.
The Highly Conserved Layer-3 Component of the HIV-1 gp120 Inner Domain Is Critical for CD4-Required Conformational Transitions
Authors: Désormeaux Anik , Coutu Mathieu , Medjahed Halima , Pacheco Beatriz , Herschhorn Alon , Gu Christopher , Xiang Shi-Hua , Mao Youdong , Sodroski Joseph , Finzi Andrés
Published: December 2012

The trimeric envelope glycoprotein (Env) of human immunodeficiency virus type 1 (HIV-1) mediates virus entry into host cells. CD4 engagement with the gp120 exterior envelope glycoprotein subunit represents the first step during HIV-1 entry. CD4-induced conformational changes in the gp120 inner domain involve three potentially flexible topological layers (layers 1, 2, and 3). Structural rearrangements between layer 1 and layer 2 have been shown to facilitate the transition of the envelope glycoprotein trimer from the unliganded to the CD4-bound state and to stabilize gp120-CD4 interaction. However, our understanding of CD4-induced conformational changes in the gp120 inner domain remains incomplete. Here, we report that a highly conserved element of the gp120 inner domain, layer 3, plays a pivot-like role in these allosteric changes. In the unliganded state, layer 3 modulates the association of gp120 with the Env trimer, probably by influencing the relationship of the gp120 inner and outer domains. Importantly, layer 3 governs the efficiency of the initial gp120 interaction with CD4, a function that can also be fulfilled by filling the Phe43 cavity. This work defines the functional importance of layer 3 and completes a picture detailing the role of the gp120 inner domain in CD4-induced conformational transitions in the HIV-1 Env trimer.
Treatment of acute cervical internal carotid artery dissection using the Solitaire FR revascularization device
Authors: To Chiu Yuen , Badr Yaser , Richards Boyd
Published: December 2012

During treatment of a right internal carotid artery terminus aneurysm, an acute iatrogenic flow limiting dissection was caused in the cervical internal carotid. The true lumen was catheterized using a Mirage 0.008 microwire over an Excelsior SL-10 microcatheter, which was exchanged for a Marksman microcatheter. A 6 mm×30 mm Solitaire FR revascularization device was then deployed across the dissection as a salvage technique.
Impact of prior probabilities of MRSA as an infectious agent on the accuracy of the emerging molecular diagnostic tests: a model simulation
Authors: Zilberberg Marya D , Shorr Andrew F
Published: December 2012

Objectives

Traditional microbiology identification takes 48–72 h to complete. This lag forces clinicians to rely on broad-spectrum empiric coverage. To address this gap, manufacturers are developing rapid molecular diagnostics (RMD). We hypothesised that RMD's accuracy is more dependent upon population risk of harbouring the culprit pathogen than to their sensitivity and specificity.

Design

A mathematical model.

Setting and participants

We used the range of risks (5–50%) for methicillin-resistantStaphylococcus aureus(MRSA) among patients hospitalised with complicated skin and skin structure infections (cSSSI), pneumonia or sepsis.

Main outcome measures

We modelled the impact of changing a test's characteristics on its positive (PPV) and negative (NPV) predictive values, and hence the risk of overtreatment or undertreatment, within strata of an organism's population prevalence. MRSA diagnostics provided assumptions for the test sensitivity and specificity (95–99%). Scenarios with low sensitivity and specificity (90%), and best-case and worst-case scenarios normalised to the annual universe of populations of interest, were examined.

Results

With a low prevalence (5%) and high test specificity, the PPV was 84%. Conversely, with 50% prevalence and 95% test specificity the PPV rose to ≥95%. Even when the test's specificity and sensitivity were both 90%, in a high-risk population both PPV and NPV were ∼90%. In the worst-case scenario, 150 000 patients with cSSSI, pneumonia and sepsis annually were at risk for inappropriate treatment, 91% of these at risk for over-treatment. In the best-case scenario, 81% of 18 000 patients at risk for inappropriate coverage were subject to overtreatment.

Conclusions

Although promising for limiting exposure to excessive antimicrobial coverage, RMDs alone will not solve the issue of inappropriate, and particularly overtreatment. Increasing pretest probability as a strategy to minimise antibiotic abuse results in more accurate patient classification than does developing a test with near-perfect characteristics. The healthcare community must build robust evidence and information technology infrastructure to guide appropriate use of such testing.
Home-based cardiac rehabilitation is an attractive alternative to no cardiac rehabilitation for elderly patients with coronary heart disease: results from a randomised clinical trial
Authors: Oerkild Bodil , Frederiksen Marianne , Hansen Jorgen Fischer , Prescott Eva
Published: December 2012

Objective

To compare home-based cardiac rehabilitation (CR) with usual care (control group with no rehabilitation) in elderly patients who declined participation in centre-based CR.

Design

Randomised clinical trial with 12 months follow-up and mortality data after 5.5 years (mean follow-up 4½ years).

Setting

Rehabilitation unit, Department of Cardiology, Copenhagen, Denmark.

Participants

Elderly patients ≥65 years with coronary heart disease.

Intervention

A physiotherapist made home visits in order to develop an individualised exercise programme that could be performed at home and surrounding outdoor area. Risk factor intervention, medical adjustment, physical and psychological assessments were offered at baseline and after 3, 6 and 12 months.

Main outcome measurements

The primary outcome was 6 min walk test (6MWT). Secondary outcomes were blood pressure, body composition, cholesterol profile, cessation of smoking, health-related quality of life (HRQoL), anxiety and depression.

Results

40 patients participated. The study population was characterised by high age (median age 77 years, range 65–92 years) and high level of comorbidity. Patients receiving home-based CR had a significant increase in the primary outcome 6MWT of 33.5 m (95% CI: 6.2 to 60.8, p=0.02) at 3 months, whereas the usual care group did not significantly improve, but with no significant differences between the groups. At 12 months follow-up, there was a decline in 6MWT in both groups; −55.2 m (95% CI: 18.7 to 91.7, p<0.01) in the home group and −52.1 m (95% CI: −3.0 to 107.1, p=0.06) in the usual care group. There were no significant differences in blood pressure, body composition, cholesterol profile, cessation of smoking or HRQoL after 3, 6 and 12 months follow-up.

Conclusions

Participation in home-based CR improved exercise capacity among elderly patients with coronary heart disease, but there was no significant difference between the home intervention and the control group. In addition, no significant difference was found in the secondary outcomes. When intervention ceased, the initial increase in exercise capacity was rapidly lost.
Family meals can help children reach their 5 A Day: a cross-sectional survey of children's dietary intake from London primary schools
Authors: Christian Meaghan S , Evans Charlotte E L , Hancock Neil , Nykjaer Camilla , Cade Janet E
Published: December 2012

Background

This study aims to explore how the home food environment and parental attitudes and values affect children's fruit and vegetable (F&V) intake.

Methods

The sample consists of 2383 children with a mean age of 8.3 years (95% CI 8.2 to 8.3) attending 52 primary schools in London. These children are taking part in two randomised controlled trials to evaluate a school gardening programme. Diet was assessed using a validated 24-h food tick list, the Child And Diet Evaluation Tool (CADET).

Results

The CADET tool found that children consumed on average 293 g F&V (95% CI 287 to 303) per day. Clustered (by school) multilevel regression models with total F&V as the primary outcome were conducted to explore how the home environment affects children's F&V intake. Children of families who reported ‘always’ eating a family meal together at a table had 125 g (95% CI 92 to 157; p=<0.001) more F&V than families who never ate a meal together. Daily consumption of F&V by parents was associated with higher F&V (88 g, 95% CI 37 to 138) intake in children compared with rarely/never consumption of F&V by parents. Cutting up fruit and vegetables for children was associated with higher consumption. Families who reported always cutting up F&V for their children had 44 g (95% CI 18 to 71) more F&V than families who never cut up F&V.

Conclusions

This study identified that cutting up F&V and family consumption of F&V facilitates children's intake. Eating a family meal together regularly could increase children's F&V intake and help them achieve the recommended intake.

Trial registration

ISRCTN11396528.
Component coding and the neurointerventionalist: a tale with an end
Authors: Hirsch Joshua A , Donovan William D , Leslie-Mazwi Thabele M , Nicola Greg N , Manchikanti Laxmaiah , Silva Ezequiel
Published: December 2012

Component coding is the method NeuroInterventionalists have used for the past 20 years to bill procedural care. The term refers to separate billing for each discrete aspect of a surgical or interventional procedure, and has typically allowed billing the procedural activity, such as catheterization of vessels, separately from the diagnostic evaluation of radiographic images. This work is captured by supervision and interpretation codes. Benefits of component coding will be reviewed in this article. The American Medical Association/Specialty Society Relative Value Scale Update Committee has been filtering for codes that are frequently reported together. NeuroInterventional procedures are going to be caught in this filter as our codes are often reported simultaneously as for example routinely occurs when procedural codes are coupled to those for supervision and interpretation. Unfortunately, history has shown that when bundled codes have been reviewed at the RUC, there has been a trend to lower overall RVU value for the combined service compared with the sum of the values of the separate services.
How doesListeria monocytogenescombat acid conditions?
Authors: Smith James L. , Liu Yanhong , Paoli George C.
Published: December 2012

Listeria monocytogenes, a major foodborne pathogen, possesses a number of mechanisms that enable it to combat the challenges posed by acidic environments, such as that of acidic foods and the gastrointestinal tract. One mechanism employed by L. monocytogenes for survival at low pH is the adaptive acid tolerance response (ATR) in which a short adaptive period at a nonlethal pH induces metabolic changes that allow the organism to survive a lethal pH. Overcoming acid conditions by L. monocytogenes involves a variety of regulatory responses, including the LisRK 2-component regulatory system, the SOS response, components of the σBregulon, changes in membrane fluidity, the F0F1-ATPase proton pump, and at least 2 enzymatic systems that regulate internal hydrogen ion concentration (glutamate decarboxylase and arginine deiminase). It is not clear if these mechanisms exert their protective effects separately or in concert, but it is probable that these mechanisms overlap. Studies using mutants indicate that the glutamate decarboxylase system can protect L. monocytogenes when the organism is present in acidic juices, yogurt, salad dressing, mayonnaise, and modified CO2atmospheres. The glutamate decarboxylase system also has a role in protecting L. monocytogenes against the acidic environment of the stomach. There is a need to study other acid resistance mechanisms of L. monocytogenes to determine their effectiveness in protecting the organism in acidic foods or during transit through the acid stomach.
Why fruits are rich in antioxidants? An opinion review,
Authors: Grover Ashok Kumar
Published: December 2012

We rarely consider whether and how plants benefit from making antioxidant-rich fruits, despite our dependence on fruits as routine sources of these compounds. The hypothesis presented here is that storage of the antioxidant materials is advantageous to the survival of the plant species. This hypothesis is based on the premise that at different stages from flower bud opening to seedling formation, the concentrations of the reactive oxygen species (ROS) needed vary tremendously. Exposing seeds of several plant species to ROS aids germination. However, ROS can cause considerable damage by mutagenesis during plant embryogenesis. It is suggested that the antioxidant-rich environment in fruits protects the developing plant embryos from this damage. It also allows for an antioxidant environment for packaging the embryos into seeds with tight seed coats. After fruit maturation and seed dispersal, a prolonged exposure to oxygen and moisture enables the seeds to produce the ROS needed for seed germination. There is a simultaneous increase in the ROS scavenging systems to allow for protection of the dividing cells afterwards. These observations are unified into the hypothesis that the antioxidant rich fruits aid in the survival of plant species, and discussed in the context of vascular plant evolution.
BUILDING MAP AND POSITIONING SYSTEM FOR INDOOR ROBOT BASED ON PLAYER
Authors: WANG BIN , LU WEI , KONG BIN
Published: December 2012

In this paper, we have proposed a map-building and positioning method for an indoor mobile robot based on the open source platform Player. First, the DP-SLAM algorithm is transplanted to the Player and used to build the dynamic offline map. This would reduce the errors and constraints caused by manual map building. Second, the KLD-Sampling Adaptive Monte Carlo Locating (KLD-AMCL) algorithm is introduced to reduce the number of particles required in locating. Meanwhile, higher accuracy of localization is achieved through calculating the MLE and the real posterior KL distance. Finally, an indoor mobile robot positioning system is built by combining the Player platform, dynamic map building and KLD-AMCL algorithm. Experimental results show that the proposed system has better environmental adaptability and higher positioning accuracy.
Almost Hadamard Matrices: General Theory and Examples
Authors: Banica Teodor , Nechita Ion , Życzkowski Karol
Published: December 2012

We develop a general theory of almost Hadamard matrices. These are by definition the matrices H ∈ MN(ℝ) having the property that [Formula: see text] is orthogonal, and is a local maximum of the 1-norm on O (N). Our study includes a detailed discussion of the circulant case (Hij= γj-i) and of the two-entry case (Hij∈ {x, y}), with the construction of several families of examples, and some 1-norm computations.
Covariant Abstract Description for a Dirac Particle
Authors: Caban Paweł , Rembieliński Jakub , Włodarczyk Marta
Published: December 2012

We give a direct link between covariant description of Dirac particles in the abstract framework of unitary representation of the Poincaré group and description with the help of the Dirac equation. In this context we discuss the spin operator for a relativistic Dirac particle. We show also that the spin operator used in quantum field theory for spin s = 1/2 corresponds to the Foldy-Wouthuysen mean-spin operator. We hope that this formalism will be useful in the theory of relativistic quantum information.
Dietary sodium intake modulates renal excretory responses to intrarenal angiotensin (1–7) administration in anesthetized rats
Authors: O'Neill Julie , Corbett Alan , Johns Edward J.
Published: December 2012

Angiotensin II at the kidney regulates renal hemodynamic and excretory function, but the actions of an alternative metabolite, angiotensin (1–7), are less clear. This study investigated how manipulation of dietary sodium intake influenced the renal hemodynamic and excretory responses to intrarenal administration of angiotensin (1–7). Renal interstitial infusion of angiotensin (1–7) in anesthetized rats fed a normal salt intake had minimal effects on glomerular filtration rate but caused dose-related increases in urine flow and absolute and fractional sodium excretions ranging from 150 to 200%. In rats maintained for 2 wk on a low-sodium diet angiotensin (1–7) increased glomerular filtration rate by some 45%, but the diuretic and natriuretic responses were enhanced compared with those in rats on a normal sodium intake. By contrast, renal interstitial infusion of angiotensin (1–7) in rats maintained on a high-sodium intake had no effect on glomerular filtration rate, whereas the diuresis and natriuresis was markedly attenuated compared with those in rats fed either a normal or low-sodium diet. Plasma renin and angiotensin (1–7) were highest in the rats on the low-sodium diet and depressed in the rats on a high-sodium diet. These findings demonstrate that the renal hemodynamic and excretory responses to locally administered angiotensin (1–7) is dependent on the level of sodium intake and indirectly on the degree of activation of the renin-angiotensin system. The exact way in which angiotensin (1–7) exerts its effects may be dependent on the prevailing levels of angiotensin II and its receptor expression.
The strength of the corticospinal coherence depends on the predictability of modulated isometric forces
Authors: Mendez-Balbuena Ignacio , Naranjo Jose Raul , Wang Xi , Andrykiewicz Agnieska , Huethe Frank , Schulte-Mönting Jürgen , Hepp-Reymond Marie-Claude , Kristeva Rumyana
Published: December 2012

Isometric compensation of predictably frequency-modulated low forces is associated with corticomuscular coherence (CMC) in beta and low gamma range. It remains unclear how the CMC is influenced by unpredictably modulated forces, which create a mismatch between expected and actual sensory feedback. We recorded electroencephalography from the contralateral hand motor area, electromyography (EMG), and the motor performance of 16 subjects during a visuomotor task in which they had to isometrically compensate target forces at 8% of the maximum voluntary contraction with their right index finger. The modulated forces were presented with predictable or unpredictable frequencies. We calculated the CMC, the cortical motor alpha-, beta-, and gamma-range spectral powers (SP), and the task-related desynchronization (TRD), as well as the EMG SP and the performance. We found that in the unpredictable condition the CMC was significantly lower and associated with lower cortical motor SP, stronger TRD, higher EMG SP, and worse performance. The findings suggest that due to the mismatch between predicted and actual sensory feedback leading to higher computational load and less stationary motor state, the unpredictable modulation of the force leads to a decrease in corticospinal synchrony, an increase in cortical and muscle activation, and a worse performance.
Source Detection and Functional Connectivity of the Sensorimotor Cortex during Actual and Imaginary Limb Movement: A Preliminary Study on the Implementation of eConnectome in Motor Imagery Protocols
Authors: Athanasiou Alkinoos , Lithari Chrysa , Kalogianni Konstantina , Klados Manousos A. , Bamidis Panagiotis D.
Published: December 2012

Introduction. Sensorimotor cortex is activated similarly during motor execution and motor imagery. The study of functional connectivity networks (FCNs) aims at successfully modeling the dynamics of information flow between cortical areas.Materials and Methods. Seven healthy subjects performed 4 motor tasks (real foot, imaginary foot, real hand, and imaginary hand movements), while electroencephalography was recorded over the sensorimotor cortex. Event-Related Desynchronization/Synchronization (ERD/ERS) of the mu-rhythm was used to evaluate MI performance. Source detection and FCNs were studied with eConnectome.Results and Discussion. Four subjects produced similar ERD/ERS patterns between motor execution and imagery during both hand and foot tasks, 2 subjects only during hand tasks, and 1 subject only during foot tasks. All subjects showed the expected brain activation in well-performed MI tasks, facilitating cortical source estimation. Preliminary functional connectivity analysis shows formation of networks on the sensorimotor cortex during motor imagery and execution.Conclusions. Cortex activation maps depict sensorimotor cortex activation, while similar functional connectivity networks are formed in the sensorimotor cortex both during actual and imaginary movements. eConnectome is demonstrated as an effective tool for the study of cortex activation and FCN. The implementation of FCN in motor imagery could induce promising advancements in Brain Computer Interfaces.
Prevention of Influenza Pandemic by Multiple Control Strategies
Authors: Ullah Roman , Zaman Gul , Islam Saeed
Published: December 2012

We present the prevention of influenza pandemic by using multiple control functions. First, we adjust the control functions in the pandemic model, then we show the existence of the optimal control problem, and, by using both analytical and numerical techniques, we investigate cost‐effective control effects for the prevention of transmission of disease. To do this, we use four control functions, the first one for increasing the effect of vaccination, the second one for the strategies to isolate infected individuals, and the last two for the antiviral treatment to control clinically infectious and hospitalization
cases, respectively. We completely characterized the optimal control and compute the numerical solution of the optimality system by using an iterative method.
A Graph‐Based Approach to Optimal Scan Chain Stitching Using RTL Design Descriptions
Authors: Zaourar Lilia , Kieffer Yann , Aktouf Chouki
Published: December 2012

The scan chain insertion problem is one of the mandatory logic insertion design tasks. The scanning of designs is a very efficient way of improving their testability. But it does impact size and performance, depending on the stitching ordering of the scan chain. In this paper, we propose a graph‐based approach to a stitching algorithm for automatic and optimal scan chain insertion at the RTL. Our method is divided into two main steps. The first one builds graph models for inferring logical proximity information from the design, and then the second one uses classic approximation algorithms for the traveling salesman problem to determine the best scan‐stitching ordering. We show how this algorithm allows the decrease of the cost of both scan analysis and implementation, by measuring total wirelength on placed and routed benchmark designs, both academic and industrial.
Modeling Airflow Using Subject-Specific 4DCT-Based Deformable Volumetric Lung Models
Authors: Ilegbusi Olusegun J. , Li Zhiliang , Seyfi Behnaz , Min Yugang , Meeks Sanford , Kupelian Patrick , Santhanam Anand P.
Published: December 2012

Lung radiotherapy is greatly benefitted when the tumor motion caused by breathing can be modeled. The aim of this paper is to present the importance of using anisotropic and subject-specific tissue elasticity for simulating the airflow inside the lungs. A computational-fluid-dynamics (CFD) based approach is presented to simulate airflow inside a subject-specific deformable lung for modeling lung tumor motion and the motion of the surrounding tissues during radiotherapy. A flow-structure interaction technique is employed that simultaneously models airflow and lung deformation. The lung is modeled as a poroelastic medium with subject-specific anisotropic poroelastic properties on a geometry, which was reconstructed from four-dimensional computed tomography (4DCT) scan datasets of humans with lung cancer. The results include the 3D anisotropic lung deformation for known airflow pattern inside the lungs. The effects of anisotropy are also presented on both the spatiotemporal volumetric lung displacement and the regional lung hysteresis.
Malignant Melanoma of the Urethra: A Rare Histologic Subdivision of Vulvar Cancer with a Poor Prognosis
Authors: Günther Veronika , Alkatout I. , Lez C. , Altarac S. , Fures R. , Cupic H. , Persec Z. , Hrgovic Z. , Mundhenke C.
Published: December 2012

Malignant melanoma of the urethra is a rare tumour that is difficult to diagnose and treat, resulting in a poor prognosis. In this paper, we present the case of a 65-year-old woman who was referred to a gynaecologist because of a urethral mass that mimicked a caruncle. The tumour was removed by local excision, and a pathological analysis revealed a malignant melanoma. Distal urethrectomy was performed after three months with no evidence of residual tumour. There was no evidence of disease at a six-year followup. In this paper, we compare the epidemiology, treatment, staging, and prognosis of vulvar cancer in general to malignant melanoma of the vulva in particular.
On the Hermitian R‐Conjugate Solution of a System of Matrix Equations
Authors: Dong Chang-Zhou , Wang Qing-Wen , Zhang Yu-Ping
Published: December 2012

Let R be an n by n nontrivial real symmetric involution matrix, that is,
R = R−1 = RT ≠ In. An n × n complex matrix A is termed R‐conjugate if
, where denotes the conjugate of A. We give necessary and sufficient
conditions for the existence of the Hermitian R‐conjugate solution to the system
of complex matrix equations AX = C and XB = D and present an expression of
the Hermitian R‐conjugate solution to this system when the solvability conditions
are satisfied. In addition, the solution to an optimal approximation problem is
obtained. Furthermore, the least squares Hermitian R‐conjugate solution with the
least norm to this system mentioned above is considered. The representation of
such solution is also derived. Finally, an algorithm and numerical examples are
given.
Atrioventricular Conduction Delay in Fetuses Exposed to Anti-SSA/Ro and Anti-SSB/La Antibodies: A Magnetocardiography Study
Authors: Wacker-Gußmann Annette , Paulsen Henrike , Kiefer-Schmidt Isabelle , Henes Joerg , Muenssinger Jana , Weiss Magdalene , Goelz Rangmar , Preissl Hubert
Published: December 2012

Background. The presence of anti-SSA/Ro and anti-SSB/La antibodies during pregnancy is associated with fetal congenital heart block (CHB), which is primarily diagnosed through fetal echocardiography. Conclusive information about the complete electrophysiology of the fetal cardiac conducting system is still lacking. In addition to echocardiography, fetal magnetocardiography (fMCG) can be used. fMCG is the magnetic analogue of the fetal electrocardiogram (ECG).Patients and Methods. Forty-eight pregnant women were enrolled in an observational study; 16 of them tested positive for anti-SSA/Ro and anti-SSB/La antibodies. In addition to routine fetal echocardiography, fMCG was used. Fetal cardiac time intervals (fCTIs) were extracted from the magnetic recordings by predefined procedures. ECGs in the neonates of the study group were performed within the first month after delivery.Results. The PQ segment of the fCTI was significantly prolonged in the study group (P=0.007), representing a delay of the electrical impulse in the atrioventricular (AV) node. Other fCTIs were within normal range. None of the anti-SSA/Ro and/or anti-SSB/La fetuses progressed to a more advanced heart block during pregnancy or after birth.Conclusion. The study identified a low-risk population within antibody positive mothers, where PQ segment prolongation is associated with a lack of progression of the disease.
Signaling Crosstalk between PPARγand BMP2 in Mesenchymal Stem Cells
Authors: Takada Ichiro , Yogiashi Yoshiko , Kato Shigeaki
Published: December 2012

Recent studies have revealed that PPARγ’s transactivation function is regulated by extracellular signals. In particular, cytokines and Wnt family proteins suppress the ligand-inducible transactivation function of PPARγand attenuate adipogenesis/osteoblastogenesis switching in mesenchymal stem cells (MSCs). For example, Wnt5a suppresses PPARγtranscriptional activity through the NLK/SETDB1/CHD7 pathway. Among these factors, BMP2 strongly induces bone formation, but the effect of BMP2 on PPARγfunction remains unclear. We examined the effect of BMP2 and PPARγin ST2 cells and found that PPARγactivation affected BMP2’s signaling pathway through epigenetic regulation. Although BMP2 did not interfere with PPARγ-mediated adipogenesis, BMP2 increased mRNA expression levels of PPARγtarget genes (such asFabp4andNr1h3) when cells were first treated with troglitazone (TRO). Moreover, PPARγactivation affected BMP2 through enhancement of histone activation markers (acetylated histone H3 and trimethylated Lys4 of histone H3) on theRunx2promoter. After TRO treatment for three hours, BMP2 enhanced the levels of active histone marks on the promoter of a PPARγtarget gene. These results suggest that the order of treatment with BMP2 and a PPARγligand is critical for adipogenesis and osteoblastogenesis switching in MSCs.
Analysis of Flavonoids fromEugenia unifloraLeaves and Its Protective Effect against Murine Sepsis
Authors: Rattmann Yanna D. , de Souza Lauro Mera , Malquevicz-Paiva Simone M. , Dartora Nessana , Sassaki Guilherme Lanzi , Gorin Philip A. J. , Iacomini Marcello
Published: December 2012

Eugenia uniflora, referred to as Pitanga cherry shrub, is largely distributed in tropical and subtropical America. This plant is cultivated in many countries and it is suitable for the production of juice, frozen pulp, and tea. Besides, it can be used as treatment for inflammatory diseases. We reported that a flavonoid-rich fraction (HE-Bu) obtained from leaves decreased the lethality induced by cecal ligation and puncture (CLP), a clinically relevant model of sepsis. The oral administration of HE-Bu reduced the late mortality rate by 30%, prevented neutrophil accumulation in lungs, decreased TNF-αand IL-1βserum levels, and markedly decreased iNOS and COX-2 protein expression by ileum cells. Chemical investigation showed myricetin and quercetin rhamnosides as the major components of this fraction. The results showed that HE-Bu protected mice from sepsis and indicated that this edible plant produces compounds that could be considered as potential adjuvants for sepsis treatment.
Electrical Potential of Acupuncture Points: Use of a Noncontact Scanning Kelvin Probe
Authors: Gow Brian J. , Cheng Justine L. , Baikie Iain D. , Martinsen Ørjan G. , Zhao Min , Smith Stephanie , Ahn Andrew C.
Published: December 2012

Objective. Acupuncture points are reportedly distinguishable by their electrical properties. However, confounders arising from skin-to-electrode contact used in traditional electrodermal methods have contributed to controversies over this claim. The Scanning Kelvin Probe is a state-of-the-art device that measures electrical potential without actually touching the skin and is thus capable of overcoming these confounding effects. In this study, we evaluated the electrical potential profiles of acupoints LI-4 and PC-6 and their adjacent controls. We hypothesize that acupuncture point sites are associated with increased variability in potential compared to adjacent control sites.Methods. Twelve healthy individuals were recruited for this study. Acupuncture points LI-4 and PC-6 and their adjacent controls were assessed. A 2 mm probe tip was placed over the predetermined skin site and adjusted to a tip-to-sample distance of 1.0 mm under tip oscillation settings of 62.4 Hz frequency. A surface potential scan spanning a 1.0 cm × 1.0 cm area was obtained.Results. At both the PC-6 and LI-4 sites, no significant differences in mean potential were observed compared to their respective controls (Wilcoxon rank-sum test, and 0.79, resp.). However, the LI-4 site was associated with significant increase in variability compared to its control as denoted by standard deviation and range ( and 0.0005, resp.). At the PC-6 site, no statistical differences in variability were observed.Conclusion. Acupuncture points may be associated with increased variability in electrical potential.