bluuebunny/crossref_metadata_2025 huggingface dataset:
Replacing Traditional Diagnostics of Fecal Viral Pathogens by a Comprehensive Panel of Real-Time PCRs
Authors: Wolffs Petra F. G. , Bruggeman Cathrien A. , van Well Gijs T. J. , van Loo Inge H. M.
Published: March 2011

Molecular DNA-based diagnostics are increasingly being used for diagnosis of viral infections. For enteric viruses, PCR assays have also been developed. The aims of this study were to compile and evaluate a comprehensive panel of PCR assays for diagnosis of viruses causing diarrheal disease and to evaluate its use in a largely pediatric population in a 750-bed university medical center. The PCR panel was designed to include assays for detection of adenovirus, astrovirus, enterovirus, norovirus, parechovirus, rotavirus, and sapovirus. The results of the PCR panel were evaluated in relation to conventional viral diagnostics consisting of viral culture and/or rotavirus and adenovirus rapid antigen tests on samples that were taken for routine diagnostics. Comparing conventional with PCR-based testing, the number of viruses detected increased dramatically from 25 to 106 when PCR assays were used. This increase was due mainly to detection of previously undetected viruses, i.e., astrovirus, norovirus, and sapovirus. In 24% of the samples, norovirus was detected. Also, the lower detection limit of PCR-based adenovirus, enterovirus, parechovirus, and rotavirus diagnostics further increased the detection rate. By focusing on samples from patients with complaints of gastroenteritis, detection of a causative agent was increased from 49% by conventional tests to 97% by molecular diagnostics. However, many samples containing low viral loads were found in patients with complaints other than intestinal complaints. In conclusion, the proposed comprehensive PCR panel with appropriate cutoff values can be used for sensitive, rapid, and clinically relevant diagnosis of gastrointestinal viruses.
Case of Mycobacterium marinum Infection with Unusual Patterns of Susceptibility to Commonly Used Antibiotics
Authors: Parrish Nicole , Luethke Ronald , Dionne Kim , Carroll Karen , Riedel Stefan
Published: March 2011

Mycobacterium marinum
, found commonly in salt water and freshwater, is the causative agent of disease in many species of fish and occasionally in humans. MICs to most antimicrobial agents are relatively low. Susceptibility testing is not routinely performed, and single-drug therapy is used for the treatment of most infections. Here, we report an infection caused by a drug-resistant
M. marinum
strain in an otherwise healthy patient.
JC Virus Variant Associated with Cerebellar Atrophy in a Patient with AIDS
Authors: Roux Damien , Bouldouyre Marie-Anne , Mercier-Delarue Séverine , Seilhean Danielle , Zagdanski Anne-Marie , Delaugerre Constance , Simon François , Molina Jean-Michel , Legoff Jerôme
Published: March 2011

The human polyomavirus JC virus (JCV) is the agent of progressive multifocal leukoencephalopathy (PML). It has also recently been involved in cerebellar atrophy. Factors involved in this entity are elusive. We present a case of a human immunodeficiency virus (HIV)-infected patient with PML and cerebellar atrophy. In addition to a compartmentalization of JCV strains between urine, cerebrospinal fluid, and cerebellum, specific rearrangements in the JCV regulatory region were observed in the cerebellum, resulting in alterations of transcription factor binding sites. Our data underline the importance of searching for JCV in HIV-infected patients with cerebellar disorders and suggest that mutations in the regulatory region may be involved in cerebellar degeneration.
Investigating Transmission of Mycobacterium bovis in the United Kingdom in 2005 to 2008
Authors: Mandal Sema , Bradshaw Louise , Anderson Laura F. , Brown Tim , Evans Jason T. , Drobniewski Francis , Smith Grace , Magee John G. , Barrett Anne , Blatchford Oliver , Laurenson Ian F. , Seagar Amie-Louise , Ruddy Michael , White P. Lewis , Myers Richard , Hawkey Peter , Abubakar Ibrahim
Published: March 2011

Due to an increase in bovine tuberculosis in cattle in the United Kingdom, we investigated the characteristics of
Mycobacterium bovis
infection in humans and assessed whether extensive transmission of
M. bovis
between humans has occurred. A cross-sectional study linking demographic, clinical, and DNA fingerprinting (using 15-locus mycobacterial interspersed repetitive-unit–variable-number tandem-repeat [MIRU-VNTR] typing) data on cases reported between 2005 and 2008 was undertaken. A total of 129 cases of
M. bovis
infection in humans were reported over the period, with a decrease in annual incidence from 0.065 to 0.047 cases per 100,000 persons. Most patients were born pre-1960, before widespread pasteurization was introduced (73%), were of white ethnicity (83%), and were born in the United Kingdom (76%). A total of 102 patients (79%) had MIRU-VNTR typing data. A total of 31 of 69 complete MIRU-VNTR profiles formed eight distinct clusters. The overall clustering proportion determined using the
n
− 1 method was 33%. The largest cluster, comprising 12 cases, was indistinguishable from a previously reported West Midlands outbreak strain cluster and included those cases. This cluster was heterogeneous, having characteristics supporting recent zoonotic and human-to-human transmission as well as reactivation of latent disease. Seven other, smaller clusters identified had demographics supporting recrudescence rather than recent infection. A total of 33 patients had incomplete MIRU-VNTR profiles, of which 11 may have yielded 2 to 6 further small clusters if typed to completion. The incidence of
M. bovis
in humans in the United Kingdom remains low, and the epidemiology is predominantly that of reactivated disease.
Methicillin-Resistant Staphylococcus aureus USA300 Clone as a Cause of Lemierre's Syndrome
Authors: Chanin Jake M. , Marcos Luis A. , Thompson Bithika M. , Yusen Roger D. , Dunne W. Michael , Warren David K. , Santos Carlos A. Q.
Published: March 2011

We describe a case of a young woman who had methicillin-resistant
Staphylococcus aureus
USA300 clone (MRSA-USA300)-associated Lemierre's syndrome and secondary necrotizing pneumonia and cerebral infarcts. We also review 11 cases of
S. aureus
-associated Lemierre's syndrome reported in the literature from 1965 to 2010. Recognition of
S. aureus
as an emergent cause of Lemierre's syndrome informs the initial empirical antibiotic choice for this life-threatening condition and may positively impact patient outcomes.
Multicenter Comparison of the Vitek 2 Antifungal Susceptibility Test with the CLSI Broth Microdilution Reference Method for Testing Caspofungin, Micafungin, and Posaconazole against Candida spp
Authors: Peterson Jess F. , Pfaller Michael A. , Diekema Daniel J. , Rinaldi Michael G. , Riebe Katherine M. , Ledeboer Nathan A.
Published: March 2011

The performance of the automated Vitek 2 (bioMérieux, Inc., Marcy l'Etoile, France) antifungal susceptibility system was compared to that of broth microdilution (BMD) for the determination of MICs of various antifungal drugs. A total of 112 challenge strains and 755 clinical isolates of
Candida
spp. were tested against caspofungin and micafungin. An additional 452 clinical isolates of
Candida albicans
were tested against posaconazole. Reference BMD MIC endpoints were established after 24 h of incubation for caspofungin and micafungin and after 48 h of incubation for posaconazole. Essential agreements (EAs) between the Vitek 2 and BMD methods for caspofungin and micafungin were 99.5% and 98.6%, respectively. EA between the Vitek 2 and BMD methods was 95.6% for posaconazole. The overall categorical agreements (CAs) between the Vitek 2 system and BMD were 99.8% for caspofungin, 98.2% for micafungin, and 98.1% for posaconazole. The Vitek 2 system reliably determined caspofungin and micafungin MICs among
Candida
spp. and posaconazole MICs among
C. albicans
isolates and demonstrated excellent quantitative and qualitative agreement with the reference BMD method.
Fatal Mycotic Aneurysms Due to Scedosporium and Pseudallescheria Infection
Authors: Ong Adrian , Blyth Christopher C. , Bency Rosamma , Vicaretti Mauro , Harun Azian , Meyer Wieland , Shingde Meena , Gilroy Nicky , Chapman Jeremy , Chen Sharon C.-A.
Published: March 2011

Angioinvasive complications of
Scedosporium
infections are rare. We report two cases of mycotic aneurysm, following apparent localized infection, due to
Scedosporium apiospermum
and
Pseudallescheria boydii
. The thoracoabdominal aorta was affected in one patient, and cerebral vessels were affected in the other. Despite voriconazole therapy and surgical resection, the patients died. Previously reported cases are reviewed.
The Alphaherpesvirus Serine/Threonine Kinase Us3 Disrupts Promyelocytic Leukemia Protein Nuclear Bodies
Authors: Jung Masany , Finnen Renée L. , Neron Casey E. , Banfield Bruce W.
Published: March 2011

Us3, a serine/threonine kinase encoded by all alphaherpesviruses, plays diverse roles during virus infection, including preventing virus-induced apoptosis, facilitating nuclear egress of capsids, stimulating mRNA translation and promoting cell-to-cell spread of virus infection. Given this diversity, the full spectrum of Us3 function may not yet be recognized. We noted, in transiently transfected cells, that herpes simplex virus type 2 (HSV-2) Us3 disrupted promyelocytic leukemia protein nuclear bodies (PML-NBs). However, PML-NB disruption was not observed in cells expressing catalytically inactive HSV-2 Us3. Analysis of PML-NBs in Vero cells transfected with pseudorabies virus (PRV) Us3 and those in Vero cells infected with Us3-null or -repaired PRV strains indicated that PRV Us3 expression also leads to the disruption of PML-NBs. While loss of PML-NBs in response to Us3 expression was prevented by the proteasome inhibitor MG132, Us3-mediated degradation of PML was not observed in infected cells or in transfected cells expressing enhanced green fluorescent protein (EGFP)-tagged PML isoform IV. These findings demonstrate that Us3 orthologues derived from distantly related alphaherpesviruses cause a disruption of PML-NBs in a kinase- and proteasome-dependent manner but, unlike the alphaherpesvirus ICP0 orthologues, do not target PML for degradation.
The Herpes Simplex Virus 1 vhs Protein Enhances Translation of Viral True Late mRNAs and Virus Production in a Cell Type-Dependent Manner
Authors: Dauber Bianca , Pelletier Jerry , Smiley James R.
Published: March 2011

The herpes simplex virus 1 (HSV-1) virion host shutoff protein (vhs) degrades viral and cellular mRNAs. Here, we demonstrate for the first time that vhs also boosts translation of viral true late mRNAs in a cell type-dependent manner and that this effect determines the viral growth phenotype in the respective cell type. Our study was prompted by the detection of stress granules, indicators of stalled translation initiation, in cells infected with vhs mutants but not in wild-type-virus-infected cells. Accumulation of true late-gene products gC and US11 was strongly reduced in the absence of vhs in HeLa cells and several other restrictive cell lines but not in Vero and other permissive cells and was independent of phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α). Polysome analysis showed that gC and US11 transcripts were poorly translated in vhs-null-virus-infected HeLa cells, while translation of a cellular mRNA was not affected. Interestingly, hippuristanol, an eIF4A inhibitor, produced a similar phenotype in HeLa cells infected with wild-type HSV-1, while Vero cells were much more resistant to the inhibitor. These results suggest that translation of true late-gene transcripts is particularly sensitive to conditions of limited access to translation factors and that vhs is able either to prevent the limiting conditions or to facilitate translation initiation under these conditions. The varied permissivity of cell lines to vhs-null infection may stem from differences in the resilience of the translation machinery or the ability to control the accumulation of mRNAs.
Activation of the Alphavirus Spike Protein Is Suppressed by Bound E3
Authors: Sjöberg Mathilda , Lindqvist Birgitta , Garoff Henrik
Published: March 2011

Alphaviruses are taken up into the endosome of the cell, where acidic conditions activate the spikes for membrane fusion. This involves dissociation of the three E2-E1 heterodimers of the spike and E1 interaction with the target membrane as a homotrimer. The biosynthesis of the heterodimer as a pH-resistant p62-E1 precursor appeared to solve the problem of premature activation in the late and acidic parts of the biosynthetic transport pathway in the cell. However, p62 cleavage into E2 and E3 by furin occurs before the spike has left the acidic compartments, accentuating the problem. In this work, we used a furin-resistant Semliki Forest virus (SFV) mutant, SFV
SQL
, to study the role of E3 in spike activation. The cleavage was reconstituted with proteinase K
in vitro
using free virus or spikes on SFV
SQL
-infected cells. We found that E3 association with the spikes was pH dependent, requiring acidic conditions, and that the bound E3 suppressed spike activation. This was shown in an
in vitro
spike activation assay monitoring E1 trimer formation with liposomes and a fusion-from-within assay with infected cells. Furthermore, the wild type, SFV
wt
, was found to bind significant amounts of E3, especially if produced in dense cultures, which lowered the pH of the culture medium. This E3 also suppressed spike activation. The results suggest that furin-cleaved E3 continues to protect the spike from premature activation in acidic compartments of the cell and that its release in the neutral extracellular space primes the spike for low-pH activation.
Identification of a Single Amino Acid Required for APOBEC3 Antiretroviral Cytidine Deaminase Activity
Authors: Dang Ying , Abudu Aierken , Son SungMo , Harjes Elena , Spearman Paul , Matsuo Hiroshi , Zheng Yong-Hui
Published: March 2011

During studies of APOBEC3 (A3) anti-human immunodeficiency virus type 1 (anti-HIV-1) mechanisms, we identified a single cysteine at position 320 (C320) that disrupts A3DE activity. This residue is located in the recently identified DNA binding domain in A3G. Replacing C320 with a corresponding tyrosine from A3F (Y307) increased A3DE antiviral activity more than 20-fold. Conversely, replacing A3F Y307 with a cysteine or inserting a similar cysteine into A3B or A3G disrupted the anti-HIV activity of A3. Further investigation uncovered that C320 significantly reduces A3DE catalytic activity.
Caveolin 1 Inhibits HIV Replication by Transcriptional Repression Mediated through NF-κB
Authors: Wang Xiao Mei , Nadeau Peter E. , Lin Shanshan , Abbott Jeffrey R. , Mergia Ayalew
Published: March 2011

Caveolin 1 (Cav-1), the scaffold protein of a specific membrane lipid raft called caveolae, has been reported to suppress HIV-1 replication. However, the mechanism by which Cav-1 inhibits HIV replication remains unclear. In this study, we investigated the mechanism by which Cav-1 inhibits HIV replication at the level of gene expression. Our results show that Cav-1 represses viral gene expression and that this suppression involves the NF-κB pathway. We used several approaches in different cell types, including primary CD4+T cells and macrophages, to demonstrate the role of nuclear factor κB (NF-κB) in Cav-1-mediated inhibition of viral expression. A mutational analysis of thecis-acting element shows that the two NF-κB sites in the U3 region of the long terminal repeat (LTR) are critical for Cav-1-mediated inhibition of viral expression. In the presence of Cav-1, phosphorylation of IKKβ, IKKα, IκBα, and NF-κB p65 is dramatically reduced, while viral gene expression is suppressed. In addition, translocation of NF-κB p65 to the nucleus decreases substantially in the presence of Cav-1. Furthermore, significant inhibition of NF-κB activation and binding to target DNA are evident in the presence of Cav-1. These results establish evidence that Cav-1 inhibits HIV replication by transcriptional repression of viral gene expression and contributes to HIV's persistent infection of macrophages.
Development and RNA-Synthesizing Activity of Coronavirus Replication Structures in the Absence of Protein Synthesis
Authors: van den Worm Sjoerd H. E. , Knoops Kèvin , Zevenhoven-Dobbe Jessika C. , Beugeling Corrine , van der Meer Yvonne , Mommaas A. Mieke , Snijder Eric J.
Published: March 2011

The RNA replication and transcription complex of coronaviruses is associated with an elaborate reticulovesicular network (RVN) of modified endoplasmic reticulum. Using cycloheximide and puromycin, we have studied the effect of translation inhibition on the RNA synthesis of severe acute respiratory syndrome coronavirus and mouse hepatitis virus. Both inhibitors prevented the usual exponential increase in viral RNA synthesis, with immunofluorescence and electron microscopy indicating that RVN development came to a standstill. Nevertheless, limited RNA synthesis was supported, implying that continued translation is not an absolute requirement and suggesting a direct link between RVN formation and accumulation of coronavirus proteins.
Identification and Characterization of a Ross River Virus Variant That Grows Persistently in Macrophages, Shows Altered Disease Kinetics in a Mouse Model, and Exhibits Resistance to Type I Interferon
Authors: Lidbury Brett A. , Rulli Nestor E. , Musso Cristina M. , Cossetto Susan B. , Zaid Ali , Suhrbier Andreas , Rothenfluh Harald S. , Rolph Michael S. , Mahalingam Suresh
Published: March 2011

Alphaviruses, such as chikungunya virus, o'nyong-nyong virus, and Ross River virus (RRV), cause outbreaks of human rheumatic disease worldwide. RRV is a positive-sense single-stranded RNA virus endemic to Australia and Papua New Guinea. In this study, we sought to establish anin vitromodel of RRV evolution in response to cellular antiviral defense mechanisms. RRV was able to establish persistent infection in activated macrophages, and a small-plaque variant (RRVPERS) was isolated after several weeks of culture. Nucleotide sequence analysis of RRVPERSfound several nucleotide differences in the nonstructural protein (nsP) region of the RRVPERSgenome. A point mutation was also detected in the E2 gene. Compared to the parent virus (RRV-T48), RRVPERSshowed significantly enhanced resistance to beta interferon (IFN-β)-stimulated antiviral activity. RRVPERSinfection of RAW 264.7 macrophages induced lower levels of IFN-β expression and production than infection with RRV-T48. RRVPERSwas also able to inhibit type I IFN signaling. Mice infected with RRVPERSexhibited significantly enhanced disease severity and mortality compared to mice infected with RRV-T48. These results provide strong evidence that the cellular antiviral response can direct selective pressure for viral sequence evolution that impacts on virus fitness and sensitivity to alpha/beta IFN (IFN-α/β).
Influence of Host Gene Transcription Level and Orientation on HIV-1 Latency in a Primary-Cell Model
Authors: Shan Liang , Yang Hung-Chih , Rabi S. Alireza , Bravo Hector C. , Shroff Neeta S. , Irizarry Rafael A. , Zhang Hao , Margolick Joseph B. , Siliciano Janet D. , Siliciano Robert F.
Published: March 2011

Human immunodeficiency virus type 1 (HIV-1) establishes a latent reservoir in resting memory CD4
+
T cells. This latent reservoir is a major barrier to the eradication of HIV-1 in infected individuals and is not affected by highly active antiretroviral therapy (HAART). Reactivation of latent HIV-1 is a possible strategy for elimination of this reservoir. The mechanisms with which latency is maintained are unclear. In the analysis of the regulation of HIV-1 gene expression, it is important to consider the nature of HIV-1 integration sites. In this study, we analyzed the integration and transcription of latent HIV-1 in a primary CD4
+
T cell model of latency. The majority of integration sites in latently infected cells were in introns of transcription units. Serial analysis of gene expression (SAGE) demonstrated that more than 90% of those host genes harboring a latent integrated provirus were transcriptionally active, mostly at high levels. For latently infected cells, we observed a modest preference for integration in the same transcriptional orientation as the host gene (63.8% versus 36.2%). In contrast, this orientation preference was not observed in acutely infected or persistently infected cells. These results suggest that transcriptional interference may be one of the important factors in the establishment and maintenance of HIV-1 latency. Our findings suggest that disrupting the negative control of HIV-1 transcription by upstream host promoters could facilitate the reactivation of latent HIV-1 in some resting CD4
+
T cells.
Genome-Scale Evolution and Phylodynamics of Equine H3N8 Influenza A Virus
Authors: Murcia Pablo R. , Wood James L. N. , Holmes Edward C.
Published: March 2011

Equine influenza viruses (EIVs) of the H3N8 and H7N7 subtypes are the causative agents of an important disease of horses. While EIV H7N7 apparently is extinct, H3N8 viruses have circulated for more than 50 years. Like human influenza viruses, EIV H3N8 caused a transcontinental pandemic followed by further outbreaks and epidemics, even in populations with high vaccination coverage. Recently, EIV H3N8 jumped the species barrier to infect dogs. Despite its importance as an agent of infectious disease, the mechanisms that underpin the evolutionary and epidemiological dynamics of EIV are poorly understood, particularly at a genomic scale. To determine the evolutionary history and phylodynamics of EIV H3N8, we conducted an extensive analysis of 82 complete viral genomes sampled during a 45-year span. We show that both intra- and intersubtype reassortment have played a major role in the evolution of EIV, and we suggest that intrasubtype reassortment resulted in enhanced virulence while heterosubtypic reassortment contributed to the extinction of EIV H7N7. We also show that EIV evolves at a slower rate than other influenza viruses, even though it seems to be subject to similar immune selection pressures. However, a relatively high rate of amino acid replacement is observed in the polymerase acidic (PA) segment, with some evidence for adaptive evolution. Most notably, an analysis of viral population dynamics provided evidence for a major population bottleneck of EIV H3N8 during the 1980s, which we suggest resulted from changes in herd immunity due to an increase in vaccination coverage.
Persistence of Multiple Genetic Lineages within Intrahost Populations of Ross River Virus
Authors: Liu Wen J. , Rourke Michelle F. , Holmes Edward C. , Aaskov John G.
Published: March 2011

We examined the structure and extent of genetic diversity in intrahost populations of Ross River virus (RRV) in samples from six human patients, focusing on the nonstructural (nsP3) and structural (E2) protein genes. Strikingly, although the samples were collected from contrasting ecological settings 3,000 kilometers apart in Australia, we observed multiple viral lineages in four of the six individuals, which is indicative of widespread mixed infections. In addition, a comparison with previously published RRV sequences revealed that these distinct lineages have been in circulation for at least 5 years, and we were able to document their long-term persistence over extensive geographical distances.
Potential energy curve of N2 revisited
Authors: Špirko Vladimír , Li Xiangzhu , Paldus Josef
Published: March 2011

Recently generated ground state potential energy curves (PECs) for the nitrogen molecule, as obtained with the reduced multireference (RMR) coupled-cluster (CC) method with singles and doubles (RMR-CCSD), and its version corrected for the secondary triples RMR-CCSD(T), using cc-pVXZ basis sets with X = D, T, and Q, as well as the extrapolated complete basis set (cbs) limit (X. Li and J. Paldus: J. Chem. Phys. 2008, 129, 054104), are compared with both the highly accurate theoretical configuration interaction PEC of Gdanitz (Chem. Phys. Lett. 1998, 283, 253) and analytic PECs obtained by fitting an extensive set of experimental data (R. J. Le Roy et al.: J. Chem. Phys. 2006, 125, 164310). These results are analyzed using a morphing procedure based on the reduced potential curve (RPC) method of Jenč. It is found that an RPC fit of both theoretical potentials can be achieved with only a few parameters. The RMR PECs are found to provide an excellent description of experimentally available vibrational levels, but significantly deviate from those of Gdanitz’s PEC for highly stretched geometries, yet still do provide a qualitatively correct PECs that lie within the region delimited by Le Roy’s analytical PECs.
Disclosure of terminal illness to patients and families: diversity of governing codes in 14 Islamic countries
Authors: Abdulhameed Hunida E , Hammami Muhammad M , Hameed Mohamed Elbushra A
Published: March 2011

Background

The consistency of codes governing disclosure of terminal illness to patients and families in Islamic countries has not been studied until now.

Objectives

To review available codes on disclosure of terminal illness in Islamic countries.

Data source and extraction

Data were extracted through searches on Google and PubMed. Codes related to disclosure of terminal illness to patients or families were abstracted, and then classified independently by the three authors.

Data synthesis

Codes for 14 Islamic countries were located. Five codes were silent regarding informing the patient, seven allowed concealment, one mandated disclosure and one prohibited disclosure. Five codes were silent regarding informing the family, four allowed disclosure and five mandated/recommended disclosure. The Islamic Organization for Medical Sciences code was silent on both issues.

Conclusion

Codes regarding disclosure of terminal illness to patients and families differed markedly among Islamic countries. They were silent in one-third of the codes, and tended to favour a paternalistic/utilitarian, family-centred approach over an autonomous, patient-centred approach.
Women's views on the moral status of nature in the context of prenatal screening decisions
Authors: García Elisa , Timmermans Danielle R M , van Leeuwen Evert
Published: March 2011

Appeals to the moral authority of nature play an important role in ethical discussions about the acceptability of prenatal testing. While opponents consider testing a dangerous violation of the moral inviolable course of nature, defenders see testing as a new step in improving dominion over nature. In this study we explored the meaning of appeals to nature among pregnant women to whom a prenatal screening test was offered and the impact of these appeals on their choices regarding the acceptance of screening. Contrary to theoretical debates we found that appeals to the moral authority of nature do not prevent women from welcoming the possibilities of controlling the outcomes of pregnancy, neither do they provide prima facie justification for (not) intervening in the natural course of events. Both acceptors and decliners believed in an inherent morality in nature that must be respected. They welcome the possibility of knowing more about the health of the fetus and to make their own reproductive decisions. Concerns for the quality of their child's life and for their capacity to assure a good life for their family and disabled child appear to play a central role in the decision regarding the use of screening. Appeals to nature can be interpreted as an attempt to justify beliefs regarding suffering that must be avoided and the impact that family interests may have on the decision. These findings have significant implications for ethical guidance in debates about the acceptability and boundaries of control of offspring characteristics by prenatal testing.
Prevalence of antimicrobial‐resistant Escherichia coli in dogs in a cross‐sectional, community‐based study
Authors: Wedley A. L. , Maddox T. W. , Westgarth C. , Coyne K. P. , Pinchbeck G. L. , Williams N. J. , Dawson S.
Published: March 2011

The prevalence of carriage of antimicrobial‐resistant (AMR) and extended‐spectrum β‐lactamase (ESBL)‐producing Escherichia coli was determined in 183 healthy dogs from a semi‐rural community in Cheshire. Isolates were tested against a panel of antimicrobials and by PCR to detect resistance genes. In the suspected ESBL‐producing isolates, the presence of bla SHV, bla TEM, bla CTX‐M and bla AmpC genes was determined by PCR and sequencing. A total of 53 (29 per cent, 95 per cent confidence interval [CI] 22.4 to 35.5 per cent) dogs carried at least one AMR E coli isolate. Twenty‐four per cent (95 per cent CI 17.9 to 30.2 per cent) of dogs carried isolates resistant to ampicillin, 19.7 per cent (95 per cent CI 13.9 to 25.4 per cent) to tetracycline and 16.9 per cent (95 per cent CI 11.5 to 22.4 per cent) to trimethoprim. A bla TEM gene was detected in 39 of 54 ampicillin‐resistant isolates, a tet(B) gene in 12 of 45 tetracycline‐resistant isolates, and a dfr gene in 22 of 33 trimethoprim‐resistant isolates. Multidrug‐resistant isolates were demonstrated in 15 per cent (28 of 183; 95 per cent CI 10.1 to 20.5 per cent) of dogs. Nine suspected ESBL‐producing E coli were isolated, of which only one was confirmed by double disc diffusion testing. Two of these isolates carried the bla TEM‐1 gene and seven carried the bla CMY‐2 gene.
ABNORMAL INTERICTAL GAMMA ACTIVITY MAY MANIFEST A SEIZURE ONSET ZONE IN TEMPORAL LOBE EPILEPSY
Authors: MEDVEDEV ANDREI V. , MURRO ANTHONY M. , MEADOR KIMFORD J.
Published: March 2011

Even though recent studies have suggested that seizures do not occur suddenly and that before a seizure there is a period with an increased probability of seizure occurrence, neurophysiological mechanisms of interictal and pre-seizure states are unknown. The ability of mathematical methods to provide much more sensitive tools for the detection of subtle changes in the electrical activity of the brain gives promise that electrophysiological markers of enhanced seizure susceptibility can be found even during interictal periods when EEG of epilepsy patients often looks 'normal'. Previously, we demonstrated in animals that hippocampal and neocortical gamma-band rhythms (30–100 Hz) intensify long before seizures caused by systemic infusion of kainic acid. Other studies in recent years have also drawn attention to the fast activity (>30 Hz) as a possible marker of epileptogenic tissue. The current study quantified gamma-band activity during interictal periods and seizures in intracranial EEG (iEEG) in 5 patients implanted with subdural grids/intracranial electrodes during their pre-surgical evaluation. In all our patients, we found distinctive (abnormal) bursts of gamma activity with a 3 to 100 fold increase in power at gamma frequencies with respect to selected by clinicians, quiescent, artifact-free, 7–20 min "normal" background (interictal) iEEG epochs 1 to 14 hours prior to seizures. Increases in gamma activity were largest in those channels which later displayed the most intensive electrographic seizure discharges. Moreover, location of gamma-band bursts correlated (with high specificity, 96.4% and sensitivity, 83.8%) with seizure onset zone (SOZ) determined by clinicians. Spatial localization of interictal gamma rhythms within SOZ suggests that the persistent presence of abnormally intensified gamma rhythms in the EEG may be an important tool for focus localization and possibly a determinant of epileptogenesis.
CLOSED-LOOP SEIZURE CONTROL WITH VERY HIGH FREQUENCY ELECTRICAL STIMULATION AT SEIZURE ONSET IN THE GAERS MODEL OF ABSENCE EPILEPSY
Authors: NELSON TIMOTHY S. , SUHR COURTNEY L. , FREESTONE DEAN R. , LAI ALAN , HALLIDAY AMY J. , MCLEAN KAREN J. , BURKITT ANTHONY N. , COOK MARK J.
Published: March 2011

A closed-loop system for the automated detection and control of epileptic seizures was created and tested in three Genetic Absence Epilepsy Rats from Strasbourg (GAERS) rats. In this preliminary study, a set of four EEG features were used to detect seizures and three different electrical stimulation strategies (standard (130 Hz), very high (500 Hz) and ultra high (1000 Hz)) were delivered to terminate seizures. Seizure durations were significantly shorter with all three stimulation strategies when compared to non-stimulated (control) seizures. We used mean seizure duration of epileptiform discharges persisting beyond the end of electrical stimulation as a measure of stimulus efficacy. When compared to the duration of seizures stimulated in the standard approach (7.0 s ± 10.1), both very high and ultra high frequency stimulation strategies were more effective at shortening seizure durations (1.3 ± 2.2 s and 3.5 ± 6.4 s respectively). Further studies are warranted to further understand the mechanisms by which this therapeutic effect may be conveyed, and which of the novel aspects of the very high and ultra high frequency stimulation strategies may have contributed to the improvement in seizure abatement performance when compared to standard electrical stimulation approaches.
EFFECT OF STIMULUS PARAMETERS IN THE TREATMENT OF SEIZURES BY ELECTRICAL STIMULATION IN THE KAINATE ANIMAL MODEL
Authors: RAJDEV POOJA , WARD MATTHEW , IRAZOQUI PEDRO
Published: March 2011

Preliminary results from animal and clinical studies demonstrate that electrical stimulation of brain structures can reduce seizure frequency in patients with refractory epilepsy. Since most researchers derive stimulation parameters by trial and error, it is unclear what stimulation frequency, amplitude and duration constitutes a set of optimal stimulation parameters for aborting seizure activity in a given patient. In this investigation, we begin to quantify the independent effects of stimulation parameters on electrographic seizures, such that they could be used to develop an efficient closed-loop prosthesis that intervenes before the clinical onset of a seizure and seizure generalization. Biphasic stimulation is manually delivered to the hippocampus in response to a visually detected electrographic seizure. Such focal, responsive stimulation allows for anti-seizure treatment delivery with improved temporal and spatial specificity over conventional open-loop stimulation paradigms, with the possibility of avoiding tissue damage stemming from excessive exposure to electrical stimulation. We retrospectively examine the effects of stimulation frequency (low, medium and high), pulse-width (low and high) and amplitude (low and high) in seizures recorded from 23 kainic acid treated rats. We also consider the effects of total charge delivered and the rate of charge delivery, and identify stimulation parameter sets that induce after-discharges or more seizures. Among the stimulation parameters evaluated, we note 2 major findings. First, stimulation frequency is a key parameter for inhibiting seizure activity; the anti-seizure effect cannot be attributed to only the charge delivered per phase. Second, an after-discharge curve shows that as the frequency and pulse-width of stimulation increases, smaller pulse amplitudes are capable of eliciting an after-discharge. It is expected that stimulation parameter optimization will lead to devices with enhanced treatment efficacies and reduced side-effect profiles, especially when used in conjunction with seizure prediction or detection algorithms in a closed-loop control application.
DETECTION OF NONLINEAR INTERACTIONS OF EEG ALPHA WAVES IN THE BRAIN BY A NEW COHERENCE MEASURE AND ITS APPLICATION TO EPILEPSY AND ANTI-EPILEPTIC DRUG THERAPY
Authors: SHERMAN DAVID , ZHANG NING , GARG SHIKHA , THAKOR NITISH V. , MIRSKI MAREK A. , WHITE MIRINDA ANDERSON , HINICH MELVIN J.
Published: March 2011

EEG and field potential rhythms established in the cortex and thalamus may accommodate the propagation of seizures. This article describes the interaction between thalamus and cortex during pentylenetetrazol (PTZ) seizures in rats with and without prior treatment with ethosuximide (ESM), a well-known antiepileptic drug (AED) that raises the threshold for seizures, was given before PTZ. The AED was given before PTZ convulsant administration. We track this thalamo-cortical association with a novel measure we have called the cross-bicoherence gain, or BISCOH. This quantity allows us to measure the spectral coherence in a purely higher order spectralmethodology. BISCOH is able to track the formation of nonlinearities at specific frequencies in the recorded EEG. BISCOH showed a strong increase in low alpha wave harmonic generationat 10 and 12.5 Hz after ESM treatment (p < 0.02 and p < 0.007, respectively). Conventional coherence failed to show distinctive and significant changes in thalamo-cortical coupling after ESM treatment at those frequencies and instead showed changes at 5 Hz. This rise in cortical rhythms is evidence of harmonic generation or new frequency formation in the thalamo-cortical system withAED therapy. BISCOH could become a powerful tool in unraveling changes in coherence due to neuroelectric modulation resulting from drug treatment or electrical stimulation.
THE TRANSITIVE CLOSURE AND RELATED ALGORITHMS OF DIGRAPH ON THE RECONFIGURABLE ARCHITECTURE
Authors: PAN TIEN-TAI , LIN SHUN-SHII
Published: March 2011

The reconfigurable architecture is a parallel computation model that consists of many processor elements (PEs) and a reconfigurable bus system. There are many variant proposed reconfigurable architectures, for example, reconfigurable mesh (R-Mesh), directional reconfigurable mesh (DR-Mesh), processor arrays with reconfigurable bus systems (PARBS), complete directional processor arrays with reconfigurable bus systems (CD-PARBS), reconfigurable multiple bus machine (RMBM), directional reconfigurable multiple bus machine (directional RMBM), and etc. In this paper, a transitive closure (TC) algorithm of digraph is proposed on the models without the directional capability (non-directional). Some related digraph problems, such as strongly connected digraph, strongly connected component (SCC), cyclic checking, and tree construction, can also be resolved by modifying our transitive closure algorithm. All the proposed algorithms are designed on a three-dimensional (3-D) n×n×n non-directional reconfigurable mesh, n is the number of vertices in a digraph D, and can resolve the respective problems in O(log d(D)) time, d(D) is the diameter of the digraph D. The cyclic checking problem can be further reduced to O(log c(D)) time, c(D) is the minimum distance of cycles in the digraph D. There exist two different approaches: the matrix multiplication approach on the non-directional models for algebraic path problems (APP) and s-t connectivity approach on the directional models. In this paper, we will use the tree construction algorithm to prove those two approaches are insufficient to resolve all digraph problems and demonstrate why our approach is so important and innovative for digraph problems on the reconfigurable models.
A BATCH VERIFICATION FOR MULTIPLE PROXY SIGNATURE
Authors: TZENG SHIANG-FENG , LEE CHENG-CHI , HWANG MIN-SHIANG
Published: March 2011

In this article, we proposed a batch verification scheme for multiple proxy signatures to reduce the proxy signature verification time. The proposed scheme is not only efficient because it does not verify each individual proxy signature separately, but also secure because it can detect forged multiple proxy signatures without failure.
NON-UNIFORM CHIRAL AND 2SC COLOR SUPERCONDUCTING PHASES, TAKING INTO ACCOUNT THE NONZERO CURRENT QUARK MASS
Authors: PARTYKA TOMASZ L.
Published: March 2011

We have shown that the possibility of the existence of the mixed phase of the non-uniform chiral (NCh) and the color superconducting (2SC) ground state depends significantly on the choice of the parameters and type of the regularization scheme. Our calculations indicate that irrespective of the choice of regularization type, in a moderate baryon density region, there is a local minimum of a system corresponding to the NCh/2SC related phase. In the 3d cutoff regularization scheme, the mixed region of the NCh and the 2SC phases exists for a broad set of NJL model parameters. However, in the Schwinger regularization scheme, if parameters are set to the vacuum values of fπ, mπ and [Formula: see text], then the mixed region of the NCh and the 2SC phases does not exist.
ON THE LOW-ENERGY SPECTRUM OF SPONTANEOUSLY BROKEN Φ4THEORIES
Authors: CONSOLI M.
Published: March 2011

The low-energy spectrum of a one-component, spontaneously broken Φ4theory is generally believed to have the same simple massive form [Formula: see text] as in the symmetric phase where 〈Φ〉 = 0. However, in lattice simulations of the 4D Ising limit of the theory, the two-point connected correlator and the connected scalar propagator show deviations from a standard massive behavior that do not exist in the symmetric phase. As a support for this observed discrepancy, we present a variational, analytic calculation of the energy spectrum E1(p) in the broken phase. This analytic result, while providing the trend [Formula: see text] at large |p|, gives an energy gap E1(0)< mh, even when approaching the infinite-cutoff limit Λ→∞ with that infinitesimal coupling λ ~ 1/ ln Λ suggested by the standard interpretation of "triviality" within leading-order perturbation theory. We also compare with other approaches and discuss the more general implications of the result.
THE UNIFIED SKYRMION PROFILES AND STATIC PROPERTIES OF NUCLEONS
Authors: JIA DUO-JIE , WANG XIAO-WEI
Published: March 2011

An unified approximated solution for symmetric Skyrmions was proposed for the SU(2) Skyrme model for baryon numbers up to 8, which take the hybrid form of a kink-like solution and that given by the instanton method. The Skyrmion profiles are examined by computing lowest soliton energy as well as the static properties of nucleons within the framework of collective quantization, with a good agreement with the exact numerical results. The comparisons with the previous computations as well as the experimental data are also presented.
ENTROPY FORCE AND SELF-GRAVITY FACTOR OF MODIFIED GRAVITY THEORIES
Authors: ZHU SHU , WU SHAO-FENG , YANG GUO-HONG
Published: March 2011

We investigate the entropy force of modified gravity theories on trapping horizons. It is shown that if the entropy force is separated as a uniform term from the variation of entropy, the associated self-gravity factor is not the simple two in Einstein gravity but is different for various gravity theories.
THERMODYNAMICS OF CONSTANT CURVATURE BLACK HOLES THROUGH SEMICLASSICAL TUNNELING
Authors: YALE ALEXANDRE
Published: March 2011

We study the semiclassical tunneling of scalar and fermion fields from the horizon of a Constant Curvature Black Hole, which is locally AdS and whose five-dimensional analogue is dual to [Formula: see text] super-Yang–Mills. In particular, we highlight the strong reliance of the tunneling method for Hawking radiation on near-horizon symmetries, a fact often hidden behind the algorithmic procedure with which the tunneling approach tends to be used. We ultimately calculate the emission rate of scalars and fermions, and hence the black hole's Hawking temperature.
THE MASS SPECTRA, HIERARCHY AND COSMOLOGY OF B-L MSSM HETEROTIC COMPACTIFICATIONS
Authors: AMBROSO MICHAEL , OVRUT BURT A.
Published: March 2011

The matter spectrum of the MSSM, including three right-handed neutrino supermultiplets and one pair of Higgs–Higgs conjugate superfields, can be obtained by compactifying the E8 ×E8 heterotic string and M-theory on Calabi–Yau manifolds with specific SU(4) vector bundles. These theories have the standard model gauge group augmented by an additional gauged U(1)B-L. Their minimal content requires that the B-L gauge symmetry be spontaneously broken by a vacuum expectation value of at least one right-handed sneutrino. In previous papers, we presented the results of a quasianalytic renormalization group analysis showing that B-L gauge symmetry is indeed radiatively broken with an appropriate B-L/electroweak hierarchy. In this paper, we extend these results by (1) enlarging the initial parameter space and (2) explicitly calculating the renormalization group equations numerically. The regions of the initial parameter space leading to realistic vacua are presented and the B-L/electroweak hierarchy computed over these regimes. At representative points, the mass spectrum for all sparticles and Higgs fields is calculated and shown to be consistent with present experimental bounds. Some fundamental phenomenological signatures of a nonzero right-handed sneutrino expectation value are discussed, particularly the cosmology and proton lifetime arising from induced lepton and baryon number violating interactions.
EINSTEIN–ROSEN STRING COSMOLOGICAL MODEL IN BARBER'S SECOND SELF-CREATION THEORY
Authors: KATORE S. D. , SHAIKH A. Y.
Published: March 2011

Field equations in the presence of cosmic string source are obtained in Barber's second self-creation theory of gravitation (Gen. Relativ. Gravit.14, 117 (1982)) with the aid of Einstein–Rosen cylindrically symmetric metric. A static vacuum model and a nonstatic exact string cosmological model are presented which represents Reddy string (Astrophys. Space Sci.286, 365 (2003)) in self-creation theory. Some physical and kinematical properties of the model are also discussed.
FIRST-PRINCIPLES STUDY OF THE ELECTRONIC, LINEAR, AND NONLINEAR OPTICAL PROPERTIES OF Li(Nb, Ta)O3
Authors: CABUK SULEYMAN
Published: March 2011

We investigate the energy band structure, total density of states, the linear, nonlinear optical (NLO) response, and the electron energy-loss spectrum for Li(Nb, Ta)O 3 using first principles calculations based on density functional theory in its local density approximation. Our calculation shows that these compounds have similar structures. The indirect band gaps of 3.39 eV (LiNbO3) and 3.84 eV (LiTaO3) at the Γ–Z direction in the Brillouin zone are found. A simple scissor approximation is applied to adjust the band energy gap from the calculations to match the experimental values. The optical spectra are analyzed and the origins of some of the peaks in the spectra are discussed in terms of calculated electronic structure. Calculations are reported for the frequency-dependent complex second-order NLO susceptibilities [Formula: see text] up to 10 eV and for zero-frequency limit [Formula: see text]. The results are compared with the theoretical calculations and the available experimental data.
APPROXIMATE SOLUTIONS OF NONLINEAR VOLTERRA INTEGRAL EQUATION SYSTEMS
Authors: YALÇINBAŞ SALIH , ERDEM KÜBRA
Published: March 2011

The purpose of this study is to implement a new approximate method for solving system of nonlinear Volterra integral equations. The technique is based on, first, differentiating both sides of integral equations n times and then substituting the Taylor series the unknown functions in the resulting equation and later, transforming to a matrix equation. By merging these results, a new system which corresponds to a system of linear algebraic equations is obtained. The solution of this system yields the Taylor coefficients of the solution function. Some numerical results are also given to illustrate the efficiency of the method.
EFFECT OF LONG-RANGE DENSITY-DISPLACEMENT TYPE INTERACTION ON SMALL POLARON
Authors: YAVIDOV BAKHROM
Published: March 2011

In this work, renormalization of effective mass of an electron due to small polaron formation is studied within the framework of Extended Holstein model. It is assumed that electron moves along one-dimensional chain of ions and interacts with ions vibrations of neighboring chain via long-range density–displacement type force. By means of exact calculations, renormalized mass of nonadiabatic small polaron is obtained at strong coupling limit. Obtained results compared with those of small polaron mass of ordinary Holstein model. An effect of ions vibrations polarization on small polaron mass is addressed.