bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytotoxicological Analysis of a gp120 Binding Aptamer with Cross-Clade Human Immunodeficiency Virus Type 1 Entry Inhibition Properties: Comparison to Conventional Antiretrovirals
Authors: de Campos Walter Rangel Lopes , Coopusamy Dayaneethie , Morris Lynn , Mayosi Bongani M. , Khati Makobetsa
Published: April 2009

The long-term cumulative cytotoxicity of antiretrovirals (ARVs) is among the major causes of treatment failure in patients infected with human immunodeficiency virus (HIV) and patients with AIDS. This calls for the development of novel ARVs with less or no cytotoxicity. In the present study, we compared the cytotoxic effects of a cross-clade HIV type 1-neutralizing aptamer called B40 with those of a panel of nonnucleoside reverse transcriptase inhibitors (NNRTIs), nucleoside reverse transcriptase inhibitors (NRTIs), protease inhibitors (PIs), and the entry inhibitor (EI) T20 in human cardiomyocytes and peripheral blood mononuclear cells. An initial screen in which cell death was used as the end-point measurement revealed that the B40 aptamer and T20 were the only test molecules that had insignificant (0.61 <
P
< 0.92) effects on the viability of both cell types at the maximum concentration used. PIs were the most toxic class (0.001 <
P
< 0.00001), followed by NNRTIs and NRTIs (0.1 <
P
< 0.00001). Further studies revealed that B40 and T20 did not interfere with the cellular activity of the cytochrome P450 3A4 enzyme (0.78 <
P
< 0.24) or monoamine oxidases A and B (0.83 <
P
< 0.56) when the activities of the enzymes were compared to those in untreated controls of both cell types. Mitochondrion-initiated cellular toxicity is closely associated with the use of ARVs. Therefore, we used real-time PCR to quantify the relative ratio of mitochondrial DNA to nuclear DNA as a marker of toxicity. The levels of mitochondrial DNA remained unchanged in cells exposed to the B40 aptamer compared to the levels in untreated control cells (0.5 >
P
> 0.06). These data support the development of B40 and related EI aptamers as new ARVs with no cytotoxicity at the estimated potential therapeutic dose.
Gene Context and DNA Rearrangements in the Carbapenemase Locus of Division II Strains of
Bacteroides fragilis
Authors: García Nuria , Gutiérrez Gloria , Lorenzo María , Vadillo Santiago , Píriz Segundo , Quesada Alberto
Published: April 2009

The
cfiA
gene is clustered in a bicistronic operon encoding an
N
-acetyltransferase and an
O
-acetyltransferase related to resistance markers. This genetic context, exclusively found in strains of
Bacteroides fragilis
division II, has been highly rearranged by the successive integration of two new mobile sequences, a miniature element and IS
Bf9
. Besides that, among the DNA polymorphisms detected in the
cfiA
locus, only the integration of IS
942
at its promoter was a determinant for expression of carbapenemase activity.
Trypanothione Reductase High-Throughput Screening Campaign Identifies Novel Classes of Inhibitors with Antiparasitic Activity
Authors: Holloway Georgina A. , Charman William N. , Fairlamb Alan H. , Brun Reto , Kaiser Marcel , Kostewicz Edmund , Novello Patrizia M. , Parisot John P. , Richardson John , Street Ian P. , Watson Keith G. , Baell Jonathan B.
Published: April 2009

High-throughput screening of 100,000 lead-like compounds led to the identification of nine novel chemical classes of trypanothione reductase (TR) inhibitors worthy of further investigation. Hits from five of these chemical classes have been developed further through different combinations of preliminary structure-activity relationship rate probing and assessment of antiparasitic activity, cytotoxicity, and chemical and in vitro metabolic properties. This has led to the identification of novel TR inhibitor chemotypes that are drug-like and display antiparasitic activity. For one class, a series of analogues have displayed a correlation between TR inhibition and antiparasitic activity. This paper explores the process of identifying, investigating, and evaluating a series of hits from a high-throughput screening campaign.
Comparison of Tigecycline and Vancomycin for Treatment of Experimental Foreign-Body Infection Due to Methicillin-Resistant
Staphylococcus aureus
Authors: Vaudaux Pierre , Fleury Bénédicte , Gjinovci Asllan , Huggler Elzbieta , Tangomo-Bento Manuela , Lew Daniel P.
Published: April 2009

Twice-daily 7-day regimens of tigecycline (7 mg/kg) and vancomycin (50 mg/kg) were compared in a rat tissue cage model of chronic foreign-body infection due to methicillin (meticillin)-resistant
Staphylococcus aureus
strain MRGR3. Subcutaneously administered tigecycline reached levels in tissue cage fluid that were nearly equivalent or slightly superior to the antibiotic MIC (0.5 μg/ml) for strain MRGR3. After 7 days, equivalent, significant reductions in bacterial counts were recorded for tigecycline-treated and vancomycin-treated rats, compared with those for untreated animals.
R964C Mutation of DNA Polymerase γ Imparts Increased Stavudine Toxicity by Decreasing Nucleoside Analog Discrimination and Impairing Polymerase Activity
Authors: Bailey Christopher M. , Kasiviswanathan Rajesh , Copeland William C. , Anderson Karen S.
Published: April 2009

The R964C mutation of human DNA polymerase γ was recently linked to stavudine (d4T)-mediated mitochondrial toxicity. We utilized pre-steady-state kinetics to determine the effect of this mutation on incorporation of natural substrate dTTP and the active metabolite of d4T (d4TTP). The R964C polymerase γ holoenzyme demonstrated a 33% decrease in dTTP incorporation efficiency and a threefold-lower d4TTP discrimination relative to that of the wild-type polymerase γ, providing a mechanistic basis for genetic predisposition to nucleoside reverse transcriptase inhibitor toxicity.
Crystal Structure of
Bacillus anthracis
Dihydrofolate Reductase with the Dihydrophthalazine-Based Trimethoprim Derivative RAB1 Provides a Structural Explanation of Potency and Selectivity
Authors: Bourne Christina R. , Bunce Richard A. , Bourne Philip C. , Berlin K. Darrell , Barrow Esther W. , Barrow William W.
Published: April 2009

Bacillus anthracis
possesses an innate resistance to the antibiotic trimethoprim due to poor binding to dihydrofolate reductase (DHFR); currently, there are no commercial antibacterials that target this enzyme in
B. anthracis
. We have previously reported a series of dihydrophthalazine-based trimethoprim derivatives that are inhibitors for this target. In the present work, we have synthesized one compound (RAB1) displaying favorable 50% inhibitory concentration (54 nM) and MIC (≤12.8 μg/ml) values. RAB1 was cocrystallized with the
B. anthracis
DHFR in the space group P2
1
2
1
2
1
, and X-ray diffraction data were collected to a 2.3-Å resolution. Binding of RAB1 causes a conformational change of the side chain of Arg58 and Met37 to accommodate the dihydrophthalazine moiety. Unlike the natural substrate or trimethoprim, the dihydrophthalazine group provides a large hydrophobic anchor that embeds within the DHFR active site and accounts for its selective inhibitory activity against
B. anthracis
.
HLA and Infectious Diseases
Authors: Blackwell Jenefer M. , Jamieson Sarra E. , Burgner David
Published: April 2009

Following their discovery in the early 1970s, classical human leukocyte antigen (HLA) loci have been the prototypical candidates for genetic susceptibility to infectious disease. Indeed, the original hypothesis for the extreme variability observed at HLA loci (H-2 in mice) was the major selective pressure from infectious diseases. Now that both the human genome and the molecular basis of innate and acquired immunity are understood in greater detail, do the classical HLA loci still stand out as major genes that determine susceptibility to infectious disease? This review looks afresh at the evidence supporting a role for classical HLA loci in susceptibility to infectious disease, examines the limitations of data reported to date, and discusses current advances in methodology and technology that will potentially lead to greater understanding of their role in infectious diseases in the future.
Endothelial Nitric Oxide Synthase Gene Polymorphisms and
Plasmodium falciparum
Infection in Indian Adults
Authors: Dhangadamajhi Gunanidhi , Mohapatra Biranchi N. , Kar Shantanu K. , Ranjit Manoranjan
Published: April 2009

To explore the hypothesis that susceptibility to cerebral malaria is influenced by genetic variation in endothelial nitric oxide synthase (eNOS), we genotyped three commonly defined polymorphic loci of eNOS, Glu
298
→Asp, intron 4 variable number of tandem repeat region, and T-786→C, in 244 patients (mean age, 36.2 years) with mild malaria and 194 patients (mean age, 35.6 years) with severe malaria belonging to same ethnic group in Orissa, an eastern Indian state. We found that there was an association of the Glu
298
→Asp substitution (
P
= 0.0037; odds ratio, 1.95; 95% confidence interval, 1.2 to 3.0) and a single unique haplotype defined by “C-b-Asp” (
P
corrected
= 0.0024) for protection against cerebral malaria. Further, the median plasma level of nitrite-nitrate was found to be increased in individuals with the Glu
298
→Asp substitution and was significantly higher in the mild malaria group (
P
≤ 0.0001), but the increase was not significant in the severe malaria group (
P
= 0.0528). These findings suggest that the Glu
298
→Asp substitution and the “C-b-Asp” haplotype may enhance eNOS expression and NO production, which leads to protection against cerebral malaria. These findings may increase our understanding of the pathogenesis of malaria.
Expression of B-Cell Activating Factor Enhances Protective Immunity of a Vaccine againstPseudomonas aeruginosa
Authors: Tertilt Christine , Joh Ju , Krause Anja , Chou Paigee , Schneeweiss Kristin , Crystal Ronald G. , Worgall Stefan
Published: April 2009

B-cell activating factor (BAFF), a member of the TNF family, is a potent cytokine with stimulatory effects on B and T cells. To evaluate the potential of transient overexpression of BAFF to enhance vaccine immunogenicity, a replication-deficient adenovirus expressing full-length murine BAFF (AdBAFF) was tested in a mouse vaccine model againstPseudomonas aeruginosa. When coadministered with heat-killedP. aeruginosa, AdBAFF mediated a significant increase in anti-P. aeruginosa-specific serum and lung mucosal antibodies and resulted in improved protection against a lethal respiratory challenge withP. aeruginosa. This effect was independent of the site of administration of AdBAFF and was observed both when AdBAFF was given simultaneously with heat-killedP. aeruginosaas well as when AdBAFF was administered 4 weeks after immunization with heat-killedP. aeruginosa. These data demonstrate that a temporal increase in systemic BAFF levels is able to augment aP. aeruginosa-specific immune response upon immunization with heat-killedP. aeruginosa, suggesting that the immune-stimulatory effects of BAFF may be exploited as a molecular adjuvant for genetic vaccines.
O-Antigen-NegativeSalmonella entericaSerovar Typhimurium Is Attenuated in Intestinal Colonization but Elicits Colitis in Streptomycin-Treated Mice
Authors: Ilg Karin , Endt Kathrin , Misselwitz Benjamin , Stecher Bärbel , Aebi Markus , Hardt Wolf-Dietrich
Published: April 2009

Lipopolysaccharide (LPS) is a major constituent of the outer membrane and an important virulence factor ofSalmonella entericasubspecies 1 serovar Typhimurium (serovar Typhimurium). To evaluate the role of LPS in eliciting intestinal inflammation in streptomycin-treated mice, we constructed an O-antigen-deficient serovar Typhimurium strain through deletion of thewbaPgene. The resulting strain was highly susceptible to human complement activity and the antimicrobial peptide mimic polymyxin B. Furthermore, it showed a severe defect in motility and an attenuated phenotype in a competitive mouse infection experiment, where the ΔwbaPstrain (SKI12) was directly compared to wild-typeSalmonella. Nevertheless, the ΔwbaPstrain (SKI12) efficiently invaded HeLa cells in vitro and elicited acute intestinal inflammation in streptomycin-pretreated mice. Our experiments prove that the presence of complete LPS is not essential for in vitro invasion or for triggering acute colitis.
Presence of the neuropeptide Y1 receptor in tenocytes and blood vessel walls in the human Achilles tendon
Authors: Bjur D , Alfredson H , Forsgren S
Published: April 2009

Background:

Questions remain concerning the mechanisms of the development of chronic pain and impaired function of tendons (tendinosis). Aspects known to occur are cell proliferation, angiogenesis and altered blood flow regulation. Neuropeptide Y (NPY) is widely distributed in the body and has powerful effects in relation to these processes. NPY has its effects via the G-protein-coupled Y receptors. There is no information concerning the presence or absence of NPY receptors in Achilles tendons or other tendons.

Objective:

To clarify the expression patterns of the NPY receptors Y1 and Y2 in normal and tendinosis Achilles tendons of humans.

Methods:

Immunohistochemical methods were used. Examination on NPY was carried out in parallel.

Results:

The tenocytes showed strong immunoreactions for the Y1 receptor. The immunoreactions were more intense in the tenocytes of tendinosis tendons than in non-tendinosis tendons. The rounded/oval tenocytes typically seen in tendinosis tendons exhibited marked Y1 receptor reactions on their exterior. Pronounced Y1 reactions were seen in the smooth muscle of the arterioles of both tendinosis and non-tendinosis tendons. No reactions for the Y2 receptor were noted. NPY was detected in nerve fascicles and in perivascular innervation.

Conclusions:

This study shows that there is a morphological correlate for the occurrence of pronounced NPY effects via the Y1 receptor in both tenocytes, especially for tendinosis tendons, and blood vessel walls in the Achilles tendon. The findings are of particular interest as NPY is known to have proliferative, angiogenic and blood vessel-regulating effects. The effects of targeting the Y1 receptor in tendinosis is an interesting task to be evaluated further.
Where do out-of-hours calls to a consultant microbiologist come from?
Authors: Humphreys H
Published: April 2009

There is little in the literature about out-of-hours calls to medical microbiologists. The calls taken by a consultant medical microbiologist over a five-year period in an Irish tertiary referral hospital were reviewed. Excluding calls on weekend mornings and significant evening positive blood cultures, the mean annual number of calls on a one-in-four rota was 89 (range 70–111). Over 90% of calls were received before midnight and 51% were from specialist registrars. Medical specialties, neurosurgery and intensive care were the most common departments seeking advice. Two-thirds of calls related to the management of an individual patient, but advice on infection prevention and control is increasingly requested. Calls out-of-hours are not insignificant but little is known about how these vary between hospitals and what contribution they make to patient care.
Effect of an intervention aimed at reducing the risk of allergic respiratory disease in bakers: change in flour dust and fungal alpha-amylase levels
Authors: Meijster T , Tielemans E , Heederik D
Published: April 2009

Introduction:

We evaluated the effect on exposure of an intervention programme, which focused on risk education and providing information on good work practices. This intervention programme was enrolled as part of a Dutch covenant in the flour processing industry (industrial bakeries, flour mills, ingredient producers).

Methods:

Data from several measurement surveys collected pre- and post-intervention were used to evaluate changes in exposure over time. All datasets contained personal measurements analysed for flour dust and fungal α-amylase contents, and contextual information was available on process characteristics, work practice, and use of control measures.

Results:

Changes in exposure over time varied substantially between sectors and jobs. For bakeries a modest downward annual trend of −2% was found for flour dust and −8% for amylase. For flour mills the annual trend for flour dust was −12%; no significant trend was observed for amylase. For ingredient producers results were generally non-significant but indicated a reduction in flour dust exposure and increase in fungal α-amylase exposure. Modest increase in use of control measures and proper work practices were reported in most sectors, especially the use of local exhaust ventilation and decreased use of compressed air.

Conclusions:

The magnitude of the observed reductions in exposure levels indicates that the sector-wide intervention strategy implemented during the covenant period had a limited overall effect. This indicates that a more rigorous approach is needed to substantially decrease the exposure levels to flour dust and related allergens and, respectively, the prevalence of associated occupational diseases.
Prunus avium: nuclear DNA study in wild populations and sweet cherry cultivars
Authors: Guarino Carmine , Santoro Simona , De Simone Luciana , Cipriani Guido
Published: April 2009

The PCR–SSR technique was used to detect nuclear DNA diversity in five wild populations of Prunus avium from deciduous forests in Italy, Slovenia, and Croatia and 87 sweet cherry accessions from different geographical areas that have been maintained in the sweet cherry collection in Italy. This sweet cherry collection includes local accessions from the Campania Region as well as accessions from different countries. Twenty-eight microsatellites, previously developed in this species, generated polymorphic amplification products. Between 2 and 14 alleles were revealed for the polymorphic loci studied, with the expected heterozygosity ranging from 0.045 to 0.831. The total probability of identity was 56.94 × 10−18. A model-based Bayesian clustering analysis identified nine distinct gene pools in cultivated P. avium. The probability that wild populations were assigned to cultivated gene pools indicated that three gene pools accounted for the genomic origin of 53% of P. avium sampled. A dendrogram was generated using UPGMA (unweighted pair group method with arithmetic averages) based on Nei genetic distance analysis. This dendrogram classified most of the genotypes into one major group with an additional group of five accessions. The results indicate that this set of SSRs is highly informative, and they are discussed in terms of the implications for sweet cherry characterization.
A Y genome specific STS marker inPseudoroegneriaandElymusspecies (Triticeae: Gramineae)Parts of this paper were derived from the thesis research that partially fulfilled the requirements of an M.S. degree earned by Mr. Pungu Okito at the Graduate School, Utah State University. This research was supported in part by the Utah Agricultural Experiment Station, Utah State University, Logan, UT 84322-4810, USA. Approved as Utah Agricultural Experiment Station journal paper No. 7973.
Authors: Okito Pungu , Mott Ivan W. , Wu Yajun , Wang Richard R.-C.
Published: April 2009

The tribe Triticeae Dumortier in the grass family (Poaceae) includes the most important cereal crops (e.g., wheat, barley, and rye) and some economically important forage grasses. Elymus L. is the largest and most complex genus in the Triticeae tribe with approximately 150 species occurring worldwide. The genomic constitutions of ~40% of Elymus species are unknown and some have unverified genomic combinations. Of those known for genome constitutions, Elymus species have a genomic formula of StH, StP, StY, StStY, StHY, StPY, or StWY. However, the origin of the Y genome is unknown because no diploid species have been identified as the Y genome donor. A putative Y genome specific random amplified polymorphic DNA (RAPD) marker was converted to a sequence tagged site (STS) marker. The reliability of this STS marker for confirming the presence of the Y genome was demonstrated using 42 accessions of Elymus. The STS-PCR for the Y genome marker was then assayed on 43 accessions of diploid Pseudoroegneria (Nevski) A. Löve species having the St genome to identify possible donors of the Y genome. A rare accession of Pseudoroegneria spicata (Pursh) A. Löve was found to possess sequences that most closely related to those from the tetraploid Elymus longearistatus (Boiss.) Tzvelev (StStYY), making P. spicata the most likely donor of the Y genome, although Pseudoroegneria libanotica (Heck.) D.R. Dewey or other Pseudoroegneria species could not be excluded. Our findings support the hypothesis that the Y genome in some Elymus species shares a progenitor genome (designated StY) with the St genome of Pseudoroegneria.
Predictors of cardiovascular fitness in sedentary men
Authors: Riou Marie-Ève , Pigeon Étienne , St-Onge Josée , Tremblay Angelo , Marette André , Weisnagel S. John , Joanisse Denis R.
Published: April 2009

The relative contribution of anthropometric and skeletal muscle characteristics to cardiorespiratory fitness was studied in sedentary men. Cardiorespiratory fitness (maximal oxygen consumption) was assessed using an incremental bicycle ergometer protocol in 37 men aged 34–53 years. Vastus lateralis muscle biopsy samples were used to assess fiber type composition (I, IIA, IIX) and areas, capillary density, and activities of glycolytic and oxidative energy metabolic pathway enzymes. Correlations (all p < 0.05) were observed between maximal oxygen consumption (L·min–1) and body mass (r = 0.53), body mass index (r = 0.39), waist circumference (r = 0.34), fat free mass (FFM; r = 0.68), fat mass (r = 0.33), the enzyme activity of cytochrome c oxidase (COX; r = 0.39), muscle type IIA (r = 0.40) and IIX (r = 0.50) fiber area, and the number of capillaries per type IIA (r = 0.39) and IIX (r = 0.37) fiber. When adjusted for FFM in partial correlations, all correlations were lost, with the exception of COX (r = 0.48). Stepwise multiple regression revealed that maximal oxygen consumption was independently predicted by FFM, COX activity, mean capillary number per fiber, waist circumference, and, to a lesser extent, muscle capillary supply. In the absence of regular physical activity, cardiorespiratory fitness is strongly predicted by the potential for aerobic metabolism of skeletal muscle and negatively correlated with abdominal fat deposition.
Impact of wall filter selection on the detection of vasomotor changes in the brachial artery: a pilot study
Authors: Johnson Michel J. , Shoemaker J. Kevin
Published: April 2009

During Doppler ultrasound assessment of blood flow, a wall filter is used to reduce or eliminate high-amplitude, low-velocity signals from the vessel wall and the surrounding tissue. This study investigated the impact of a range of wall filters (22 Hz, 75 Hz, 128 Hz, and 252 Hz) on the accuracy of forearm blood flow monitoring during the sympathoexcitatory application of lower body negative pressure, when peripheral blood flow may decrease substantially. The 252 Hz filter eliminated diastolic flow in 4 of 10 participants. In the remaining participants, the 252 Hz filter minimized the sensitivity of the pulsatility index. The interpretation of physiological responses could ultimately be compromised by using filters beyond 128 Hz.
Effect of the transition from high school to university on anthropometric and lifestyle variables in malesPresented in part at the Canadian Society for Nutritional Sciences, Canadian Nutrition Congress, held in Winnipeg, Manitoba, from 18–21 June 2007.
Authors: Pullman Allison W. , Masters Rachel C. , Zalot Lindsay C. , Carde Lauren E. , Saraiva Michelle M. , Dam Yian Yian , Randall Simpson Janis A. , Duncan Alison M.
Published: April 2009

The obesity epidemic in North America has focused attention on the health risks of excess weight gain. The transition from high school to university is a critical period for weight gain, commonly referred to as the Freshman 15. The purpose of this study was to investigate the effect of the transition from high school to university on anthropometrics and physical and sedentary activities in males. A total of 108 males completed 3 study visits: the summer prior to first year university, and the ends of the first and second semesters. Outcome measures were body mass, height, body mass index (BMI), body fat, waist circumference, hip circumference, waist:hip ratio, dietary intake, and participation in physical and sedentary activities. Between the summer prior to and the end of first year university, male students experienced a significant weight gain, of 3.0 kg, with significant increases in BMI, body fat, waist circumference, hip circumference, and waist:hip ratio. Energy and nutrient intake did not change. Final body mass was significantly predicted by intention for body mass to stay the same, relative to weight loss intention. Fast aerobic physical activity significantly decreased between the summer prior to and the end of first year university, while slow aerobic physical activity, strength training, and flexibility training did not change. Computer and studying time significantly increased, while television time and hours of nightly sleep significantly decreased between the summer prior to and the end of first year university. Weekly alcoholic drinks and binge drinking frequency significantly increased over this time period. In conclusion, between the summer prior to and the end of first year university, male students gained an average of 3.0 kg, with increases in related anthropometrics. These changes may be due to body mass change intention and (or) the observed decreased physical and increased sedentary activities, but appear to be unrelated to dietary intake.
Sequencing and modular analysis of the hybrid non-ribosomal peptide synthase – polyketide synthase gene cluster from the marine sponge Hymeniacidon perleve-associated bacterium Pseudoalteromonas sp. strain NJ631
Authors: Zhu Peng , Zheng Yanling , You Yurong , Yan Xiaojun , Shao Jianzhong
Published: April 2009

In the present study, we sought to confirm a putative non-ribosomal peptide synthase (NRPS) – polyketide synthase (PKS) gene cluster in marine sponge–associated bacterium with cytotoxic activity and elucidate the gene’s structural information. The genomic library of the marine sponge Hymeniacidon perleve –associated bacterium Pseudoalteromonas sp. strain NJ631 was constructed using a pCC1FOS fosmid. Positive clones that covered the whole gene cluster region of hybrid NRPS–PKS were selected for shotgun sequencing. The results obtained from BlastX and open reading frame (ORF) analysis indicated that there are 3 big ORFs, NJA1, NJA2, and NJA3, that encoded proteins with similarities to amino acid adenylation, β-ketoacyl synthase, and non-ribosomal peptide synthase, respectively, from different organisms. The results gave us a clue that there could be PKS or NRPS modules in the 3 ORFs. Further analysis demonstrated 3 ORFs encoding 2 NRPS modules, 1 PKS module, and 3 NRPS modules. Using the specificity-conferring selection rule, the substrate specificity of 4 adenylation (A) domains (A2, A3, A4, and A5) were successfully predicted, and the amino acids of the substrate specificity were glutamic acid – glutamine, serine, d-serine, and Aeo (2-amino-9,10-epoxy-8-oxodecanoic acid), respectively.
Development of a LUX real-time PCR for the detection and quantification of human herpesvirus 7
Authors: Bergallo Massimiliano , Costa Cristina , Terlizzi Maria Elena , Sidoti Francesca , Margio Samuela , Astegiano Sara , Ponti Renata , Cavallo Rossana
Published: April 2009

Human herpesvirus 7 is a highly seroprevalent β-herpesvirus that, following primary infection, remains latent in CD4+ T cells and determines a persistent rather than a latent infection in various tissues and organs, including the lung and skin. This paper describes the development of an in-house light upon extension real-time PCR assay for quantification of human herpesvirus 7 DNA in clinical samples. The efficiency, sensitivity, specificity, inter- and intra-assay variability, and dynamic range have been determined. Subsequently, the assay has been validated by evaluating the human herpesvirus 7 load in bronchoalveolar lavages and skin specimens, chosen as 2 persistency sites, from healthy and pathological individuals. The real-time PCR assay developed in this study could be a useful tool to detect and quantify human herpesvirus 7 DNA in different clinical specimens to elucidate its epidemiological and pathogenic roles.
Regulation of pyrimidine formation inPseudomonas lundensis
Authors: West Thomas P.
Published: April 2009

The regulation of pyrimidine formation in the food spoilage agent Pseudomonas lundensis ATCC 49968 by pyrimidines was examined. In P. lundensis cells grown on glucose as a carbon source, the enzymes aspartate transcarbamoylase, dihydroorotase, and orotidine 5′-monophosphate decarboxylase were induced by orotic acid. Pyrimidine auxotrophs containing reduced transcarbamoylase or orotate phosphoribosyltransferase activity were isolated using chemical mutagenesis and selection procedures. Independent of carbon source, the maximum derepression of enzyme activity was observed for orotidine 5′-monophosphate decarboxylase after pyrimidine limitation of either auxotroph. In the glucose-grown cells of the transcarbamoylase mutant strain, orotic acid induced dihydroorotase and decarboxylase activities. Aspartate transcarbamoylase activity in succinate-grown P. lundensis cells was highly regulated by pyrophosphate as well as by pyrimidine and purine ribonucleotides. It was concluded that pyrimidine formation in P. lundensis was controlled both at the level of de novo pyrimidine biosynthetic enzyme synthesis and at the level of transcarbamoylase activity.
Optimizing the selection process of yeast starter cultures by preselecting strains dominating spontaneous fermentations
Authors: Pulvirenti Andrea , Rainieri Sandra , Boveri Silvio , Giudici Paolo
Published: April 2009

We propose an efficient and time-saving strategy for starter culture selection. Our approach is based on the accomplishment of 3 phases: (i) the selection of yeast strains dominating spontaneous fermentations, (ii) the selection among the dominant strains of those showing the best technological characteristics, and (iii) the final selection among good technological strains of those showing the desired qualitative traits. We applied this approach to wine fermentations, even though the same strategy has the potential to be employed for the selection of any type of starter culture. We isolated and identified yeast strains at the mid- and final stages of 6 spontaneous fermentations carried out in 3 different Spanish wineries. We identified all strains as Saccharomyces cerevisiae by restriction fragment length polymorphism of the ribosomal DNA internal transcribed spacer region, and subsequently distinguished each strain by analyzing the polymorphism of the inter-δ regions. Strains that were detected both at the mid- and final stages of the fermentation were considered dominant. Four dominant strains were finally selected and tested in pilot-scale fermentation, and their performance was compared with that of a commercial wine strain. All dominant strains showed good fitness and resulted suitable to be employed as starter cultures. One of the dominant strains isolated in this study is currently commercialized.
Effects of β-adrenergic receptor blockers on cardiac function: a comparative study in male versus female ratsThis article is one of a selection of papers from the NATO Advanced Research Workshop on Translational Knowledge for Heart Health (published in part 2 of a 2-part Special Issue).
Authors: Tuncay Erkan , Seymen Ali Aytac , Sam Pinar , Gurdal Hakan , Turan Belma
Published: April 2009

In heart disease, differences exist between women and men with respect to the impact of risk factors, symptoms, and therapeutic responses. The use of β-adrenergic receptor blockers is now well established in the treatment of mild and moderate systolic heart failure. Although there are significant differences among agents, their clinical effects are predictable. To address the question of sex disparities in the heart, however, we investigated the effect of treatment with the nonselective β-blockers timolol and propranolol on mechanical and electrical function of heart preparations from male and female rats. We examined the long-term effects of intragastric treatment with timolol (5 mg/kg per day) or propranolol (25 mg/kg per day) for 7 months on the hemodynamic and intracellular action potential parameters of the heart. Chronic administration of timolol but not propranolol produced a significant increase in the baseline activity of the left ventricular developed pressure (LVDP) in both male and female rats with no significant effect on the left ventricular end-diastolic pressure. Timolol or propranolol treatment of male rats and timolol but not propranolol treatment of female rats induced significant shortening in the repolarization phases of action potentials recorded from left ventricular papillary muscle strips of the hearts. The responses of LVDP to β-adrenergic stimulation were similar in timolol- or propranolol-treated or untreated male rats. On the other hand, timolol treatment markedly increased, and propranolol treatment significantly decreased, the responses of increase in LVDP in female rats. Our results suggest that although treatment with β-blockers for 7 months confirmed the role of the β-adrenergic pathway in heart function, there are marked differences in the effects of individual β-blockers on heart physiology. Sex differences should be taken into consideration when using β-blockers during experimental studies and clinical therapy.
Habitat, movements, and behaviour of overwintering Blanding’s turtles (Emydoidea blandingii) in Nova Scotia
Authors: Newton Erica J. , Herman Thomas B.
Published: April 2009

The overwintering ecology of a disjunct population complex of Blanding’s turtles ( Emydoidea blandingii (Holbrook, 1838)) in southwestern Nova Scotia was studied from January 2005 to April 2006. Sites were visited biweekly. We recorded structural characteristics and dissolved oxygen (DO), pH, and water and substrate temperatures in 7 overwintering sites containing at least 46 turtles and 7 paired “control sites”. Twenty-five adult turtles were radio-tracked to record locations and movements. Median winter temperature ranged from 0.8 to 8.6 °C in the organic substrate and from 0.3 to 7.6 °C in the water column. In overwintering sites, median DO ranged from 2.8 to 11.3 mg/L and median pH ranged from 4.6 to 5.5. Blanding’s turtles can tolerate submergence under ice for at least 3 months in severely hypoxic conditions. Movement was positively correlated with water temperature. Although some moderate movements were made during winter, 90% were less than 5 m. Movement to overwintering sites (September to mid-November) was gradual, but departure (late March to April) was rapid. Physical characteristics and environmental variables varied dramatically among overwintering sites, and no consistent patterns were observed between overwintering and control sites. We suggest that Blanding’s turtles return to communal sites year after year because of site fidelity and mating opportunities.
QUANTIZATION OF SINGULAR REDUCTION
Authors: BATES L. , CUSHMAN R. , HAMILTON M. , ŚNIATYCKI J.
Published: April 2009

This paper creates a theory of quantization of singularly reduced systems. We compare our results with those obtained by quantizing algebraically reduced systems. In the case of a Kähler polarization, we show that quantization of a singularly reduced system commutes with reduction, thus generalizing results of Sternberg and Guillemin. We illustrate our theory by treating an example of Arms, Gotay and Jennings where algebraic and singular reduction at the zero level of the momentum mapping differ. In spite of this, their quantizations agree.
THE COSMOLOGICAL CONSTANT PROBLEM AND INFLATION IN THE STRING LANDSCAPE
Authors: HUANG QING-GUO , HENRY TYE S.-H.
Published: April 2009

An earlier paper points out that a quantum treatment of the string landscape is necessary. It suggests that the wave function of the universe is mobile in the landscape until the universe reaches a meta-stable site with its cosmological constant Λ0 smaller than the critical value Λc, where Λc is estimated to be exponentially small compared to the Planck scale. Since this site has an exponentially long lifetime, it may well be today's universe. We investigate specific scenarios based on this quantum diffusion property of the cosmic landscape and find a plausible scenario for the early universe. In the last fast tunneling to the Λ0(<Λc) site in this scenario, all energies are stored in the nucleation bubble walls, which are released to radiation only after bubble collisions and thermalization. So the Λ0 site is chosen even if Λ0 plus radiation is larger than Λc, as long as the radiation does not destabilize the Λ0 vacuum. A consequence is that inflation must happen before this last fast tunneling, so the inflationary scenario that emerges naturally is extended brane inflation, where the brane motion includes a combination of rolling, fast tunnelings, slow-roll, hopping and percolation in the landscape. We point out that, in the brane world, radiation during nucleosynthesis are mostly on the standard model branes (brane radiation, as opposed to radiation in the bulk). This distinction may lead to interesting dynamics. We consider this paper as a road map for future investigations.
EXPLANATION OF OPTICAL CONDUCTIVITY IN THE FERROMAGNETIC METALLIC STATE OF La0.7Ca0.3MnO3 MANGANITES
Authors: VARSHNEY DINESH , MANSURI I. , KAURAV N.
Published: April 2009

Calculations of the optical conductivity σ(ω) for hole-doped cubic La 0.7 Ca 0.3 MnO 3 manganites have been made within the two-component scheme. One is the coherent Drude free carrier excitations. The other is the incoherent motion of carriers from one site to another leading to a polaron formation. This originated from interband transitions between the Hund rule split bands ( Mn – Mn ) and is due to charge-transfer transitions between the O 2p and the Mn eg bands. The model successfully accounts for the anomalies reported in the optical measurements for the ferromagnetic metallic state. The frequency-dependent relaxation rates are expressed in terms of memory functions and the coherent Drude carriers from the effective interaction potential leads to a sharp peak at zero frequency and a long tail at higher frequencies, i.e. in the infrared region. The hopping of carriers from Mn site to Mn and Mn site to O (incoherent motion of doped carriers) yields two peak values around 0.4 and 4.0 eV in the optical conductivity centered in the mid-infrared region. Both the Drude and hopping carriers in the manganites contribute to the optical process of conduction in the Mn – O planes and shows similar results on optical conductivity in the mid-infrared as well as infrared frequency regions as those revealed from experiments.
COMPUTER SIMULATION OF ZnO FIELD-EFFECT TRANSISTOR FOR HIGH-POWER AND HIGH-TEMPERATURE APPLICATIONS USING THE MONTE CARLO METHOD
Authors: ARABSHAHI H.
Published: April 2009

The steady-state and transient electron transport in ZnO field effect transistor have been studied using an ensemble Monte Carlo simulation which takes into account the hot-electron transport phenomena. The simulated device geometries and doping are matched to the nominal parameters described for the experimental structures as closely as possible, and the predicted I–V and transfer charateristics for the intrinsic devices show fair agreement with the available experimental data. Simulations of the effect of modulating the gate bias have also been carried out to test the device response and derived the frequency bandwidth. The value of 80 ± 5 GHz has been derived for the intrinsic current gain cut-off frequency of the ZnO MESFETs.
A MOLECULAR DYNAMICS SIMULATION STUDY OF THE POLYHEDRAL STRUCTURE OF LIQUID ARGON DURING GLASS TRANSITION
Authors: LI CONG , WANG DAN , LI JIAYUN , DUAN YONGPING , LI MEILI , YAN YUAN , SUN MINHUA
Published: April 2009

Polyhedron structures changes in Lennard–Jones (LJ) liquid argon containing 108 atoms are investigated by means of molecular dynamics (MD) simulations during the glass transition. The local bond orientational parameter and the bond angle distribution are calculated. In particular, a new parameter is introduced to simultaneously quantify the changes of all the major polyhedral structures: tetrahedron, hexahedron, octahedron, dodecahedron, and icosahedron. The results show that icosahedral order, hexahedral order and octahedral order increase with decreasing temperature, while tetrahedral order and dodecahedral order decrease. This indicates that the glass transition is a solidification process with complex microstructure changes.
A FUZZY MULTI-OBJECTIVE BILEVEL DECISION SUPPORT SYSTEM
Authors: GAO YA , ZHANG GUANGQUAN , LU JIE
Published: April 2009

In a bilevel decision problem, both the leader and the follower may have multiple objectives, and the coefficients involved in these objective functions or constraints may be described by some uncertain values. To express such a situation, a fuzzy multi-objective bilevel (FMOBL) programming model and related solution methods are introduced. This research develops a FMOBL decision support system through implementing the proposed FMOBL methods.
A CONSENSUS MODEL FOR GROUP DECISION MAKING PROBLEMS WITH UNBALANCED FUZZY LINGUISTIC INFORMATION
Authors: CABRERIZO F. J. , ALONSO S. , HERRERA-VIEDMA E.
Published: April 2009

Most group decision making (GDM) problems based on linguistic approaches use symmetrically and uniformly distributed linguistic term sets to express experts' opinions. However, there exist problems whose assessments need to be represented by means of unbalanced linguistic term sets, i.e. using term sets that are not uniformly and symmetrically distributed. The aim of this paper is to present a consensus model for GDM problems with unbalanced fuzzy linguistic information. This consensus model is based on both a fuzzy linguistic methodology to deal with unbalanced linguistic term sets and two consensus criteria, consensus degrees, and proximity measures. To do so, we use a new fuzzy linguistic methodology improving another approach to manage unbalanced fuzzy linguistic information,1 (Int. J. Intell. Syst.22(11) (2007) 1197–1214), which uses the linguistic 2-tuple model as representation base of unbalanced fuzzy linguistic information. In addition, the consensus model presents a feedback mechanism to help experts for reaching the highest degree of consensus possible. There are two main advantages provided by this consensus model. First, its ability to cope with GDM problems with unbalanced fuzzy linguistic information overcoming the problem of finding different discrimination levels in linguistic term sets. Second, it supports the consensus process automatically, avoiding the possible subjectivity that the moderator can introduce in this phase.
A MULTI-CAMERA VIEW DIRECTION PLANNING STRATEGY FOR MOBILE ROBOTS
Authors: XU TINGTING , KÜHNLENZ KOLJA , BUSS MARTIN
Published: April 2009

A multi-camera view direction planning strategy for mobile robots is discussed. Two concurrent tasks for efficient and safe locomotion in dynamic environments are considered: self-localization and dynamic object tracking. The approach is to assign different tasks to different cameras, such that for each task an individual optimal view direction is selected based on information gain maximization. Thereby, the individual task performance is improved significantly. The performance of the proposed strategy is evaluated in simulations considering a humanoid robot navigation scenario and compared with two conventional multi-camera view direction planning strategies.
Synthesis and properties of macrodiscotic triphenylenophthalocyanines
Authors: Cammidge Andrew N. , Gopee Hemant
Published: April 2009

Phthalocyanines present a flat, disk-like molecular profile and suitably substituted derivatives show discotic liquid crystalline behavior. Extension of the molecular π-system through benzofusion perturbes the phthalocyanine's basic properties, most notably shifting the absorption to longer wavelength. This paper describes our synthesis of triphenylenophthalocyanines where the benzene rings of phthalocyanines are replaced by triphenylene units. The resulting materials are macrodiscotic in nature. They show red-shifted absorption spectra and columnar mesophase behavior over a wide temperature range.
Triple-decker cadmium phthalocyanine sandwich complexes: self-assembled EPR active complexes
Authors: Chambrier Isabelle , Swarts Jannie C. , Hughes David L. , Cook Michael J.
Published: April 2009

The discovery and characterization of the first example of a bis-cadmiumtris-phthalocyanine triple-decker sandwich complex is reviewed. The compound, with each Pc ring substituted at the eight non-peripheral positions with hexyl chains, was obtained unexpectedly during recrystallization of the corresponding monomeric 1,4,8,11,15,18,22,25-octa-hexyl cadmium phthalocyanine from CH 2 Cl 2 and methanol. The scope for obtaining further examples of this new class of complex bearing different ring substituents is also described. A feature of the compounds is that they give an EPR signal. An electrochemical study has shown that the rest state of the core of the sandwich structure is a dianion arising from the imbalance of the charges on the two cadmium atoms and the three Pc 2- ligands. This is a spin 0 species. It is proposed that the free radical character arises because the potential for the first one-electron oxidation is unusually low for a phthalocyanine, allowing for the partial presence of the spin ½ species for non-peripherally substituted complexes and a more extensive presence of the EPR active redox state for peripherally substituted analogs. Results of chemical oxidation using iodine are also discussed. A spectroscopic and electrochemical study on the monomeric precursors revealed the mode of formation of the triple-decker complexes. It has been established that octa-alkyl cadmium phthalocyanines unexpectedly exist very predominantly as dimeric structures in CH 2 Cl 2 and these are proposed to be intermediates in the formation of the triple-decker complexes. Results from a series of cross experiments using differently substituted Pcs indicate that cadmium can be scrambled between a CdPc and a metal-free Pc . Furthermore, when either species is added to a solution of a triple-decker complex, the ligand from the added species becomes incorporated into new "mixed" triple-decker complexes. From these results it is proposed that the triple-decker structures are formed by self-assembly processes and that they can disassemble and reassemble in the solution phase. Preliminary measurements have identified ring substitution patterns that lead to higher oligomers.
Synthesis and structure of isocorrole metal complexes
Authors: Setsune Jun-ichiro , Tsukajima Aki , Okazaki Naho
Published: April 2009

gem-dimethylisocorrole gave four-coordinate Ni (II) and Cu (II) complexes, five-coordinate (chloro) Fe (III) and (chloro) Mn (III) complexes, and six-coordinate (chloro)(pyridinato) Rh (III) complex in moderate to good yields. The dinuclear complexes such as the μ-oxo-diiron(III) complex and tetracarbonyldirhodium(I) complex were also prepared. The structures of these mononuclear and dinuclear complexes were determined by X-ray crystallography. These structures are very similar to those of the corresponding metaloporphyrins but the presence of the sp3-meso carbon allows tilting of the pyrrole rings so as to adapt itself to various metal coordination geometries.