bluuebunny/crossref_metadata_2025 huggingface dataset:
Review of the first 1502 cases of ECG‐ST waveform analysis during labour in a teaching hospital
Authors: Doria V , Papageorghiou AT , Gustafsson A , Ugwumadu A , Farrer K , Arulkumaran S
Published: September 2007

Objective  To assess the impact of introduction of the STAN monitoring system.

Study design  Prospective observational study.

Setting  Tertiary referral labour ward, St George’s Hospital, London.

Population  High‐risk term pregnancies.

Methods  We report all consecutive cases of intrapartum monitoring using the STAN S 21 fetal heart monitor. Cases with adverse neonatal outcome were evaluated in relation to the ST waveform analysis and cardiotocography (CTG).

Main outcome measures  Cord artery metabolic acidosis, neonatal encephalopathy (NNE) and reasons behind cases with poor outcome.

Results  Between 2002 and 2005, there were 1502 women monitored by STAN. Based on combined STAN analysis in the 1502 women, action was indicated in 358 women (23.8%), while in 1108 women (73.8%) no action was indicated. Traces were not interpretable in 36 women (2.4%). Of the 836 cases (55.7%) where cord blood gases were available, there were 23 cases (2.8%) of metabolic acidosis and 16 of these (70%) were identified by STAN. Overall, there were 14 cases of NNE monitored by STAN. Retrospective analysis of these highlights human errors, such as poor CTG interpretation, delay in taking appropriate action and not following the guidelines.

Conclusions  Our experience suggests the need for more intense training on interpretation of CTG and strict adherence to guidelines.
Risk factors for anal sphincter tears: the importance of maternal position at birth
Authors: Gottvall K , Allebeck P , Ekéus C
Published: September 2007

Objective  To assess the role of birth position in the occurrence of anal sphincter tears (AST).

Design  Observational cohort study.

Setting  South Hospital in Stockholm, a teaching hospital with around 5700 births per year.

Population  Among all 19 151 women who gave birth at the South Hospital during the study period 2002–05, 12 782 women met the inclusion criteria of noninstrumental, vaginal deliveries.

Methods  Data on birth position and other obstetric factors were analysed in relation to occurrence of AST.

Main outcome measure  Third‐ and fourth‐degree AST.

Results  AST occurred in 449 women (3.5%). The trauma was more frequent in primiparous (5.8%) than in multiparous women (1.7%). The highest proportion of AST was found among women who gave birth in lithotomy position (6.9%), followed by squatting position (6.4%). Logistic regression analyses showed that lithotomy (adjusted OR 2.02, 95% CI 1.58–2.59) and squatting positions (adjusted OR 2.05, 95% CI 1.09–3.82) were associated with a significantly increased risk for AST. Other major risk factors for anal sphincter trauma were primiparity (adjusted OR 3.29, 95% CI 2.55–4.25), prolonged second stage of labour >1 hour (adjusted OR 1.52, 95% CI 1.11–2.10), infant birthweight more than 4 kg (adjusted OR 2.12, 95% CI 1.64–2.72) and large infant head circumference (adjusted OR 1.57, 95% CI 1.23–1.99).

Conclusion  Lithotomy and squatting position at birth were associated with an increased risk for AST also after control for other risk factors.
A ribosomal DNA‐based framework for the detection and quantification of stress‐sensitive nematode families in terrestrial habitats
Authors: HOLTERMAN MARTIJN , RYBARCZYK KATARZYNA , VAN DEN ELSEN SVEN , VAN MEGEN HANNY , MOOYMAN PAUL , SANTIAGO REYES PEÑA , BONGERS TOM , BAKKER JAAP , HELDER JOHANNES
Published: September 2007

Indigenous communities of soil‐resident nematodes have a high potential for soil health assessment as nematodes are diverse, abundant, trophically heterogeneous and easily extractable from soil. The conserved morphology of nematodes is the main operational reason for their under‐exploitation as soil health indicators, and a user‐friendly biosensor system should preferably be based on nonmorphological traits. More than 80% of the most environmental stress‐sensitive nematode families belong to the orders Mononchida and Dorylaimida. The phylogenetic resolution offered by full‐length small subunit ribosomal DNA (SSU rDNA) sequences within these two orders is highly different. Notwithstanding several discrepancies between morphology and SSU rDNA‐based systematics, Mononchida families (indicated here as M1–M5) are relatively well‐supported and, consequently, family‐specific DNA sequences signatures could be defined. Apart from Nygolaimidae and Longidoridae, the resolution among Dorylaimida families was poor. Therefore, a part of the more variable large subunit rDNA (≈ 1000 bp from the 5′‐end) was sequenced for 72 Dorylaimida species. Sequence analysis revealed a subclade division among Dorylaimida (here defined as D1–D9, PP1–PP3) that shows only distant similarity with ‘classical’ Dorylaimid systematics. Most subclades were trophically homogeneous, and — in most cases — specific morphological characteristics could be pinpointed that support the proposed division. To illustrate the practicability of the proposed molecular framework, we designed primers for the detection of individual subclades within the order Mononchida in a complex DNA background (viz. in terrestrial or freshwater nematode communities) and tested them in quantitative assays (real‐time polymerase chain reaction). Our results constitute proof‐of‐principle for the concept of DNA sequence signatures‐based monitoring of stress sensitive nematode families in environmental samples.
DNA BARCODING: CO1 DNA barcoding amphibians: take the chance, meet the challenge
Authors: SMITH M. ALEX , POYARKOV NIKOLAI A. , HEBERT PAUL D. N.
Published: September 2007

Although a mitochondrial DNA barcode has been shown to be of great utility for species identification and discovery in an increasing number of diverse taxa, caution has been urged with its application to one of the most taxonomically diverse vertebrate groups — the amphibians. Here, we test three of the perceived shortcomings of a CO1 DNA barcode's utility with a group of Holarctic amphibians: primer fit, sequence variability and overlapping intra‐ and interspecific variability. We found that although the CO1 DNA barcode priming regions were variable, we were able to reliably amplify a CO1 fragment from degenerate primers and primers with G‐C residues at the 3′ end. Any overlap between intra‐ and interspecific variation in our taxonomic sampling was due to introgressive hybridization (Bufo/Anaxyrus), complex genetics (Ambystoma) or incomplete taxonomy (Triturus). Rates of hybridization and species discovery are not expected to be greater for amphibians than for other vertebrate groups, and thus problems with the utility of using a single mitochondrial gene for species identification will not be specific to amphibians. Therefore, we conclude that there is greater potential for a CO1 barcode's use with amphibians than has been reported to date. A large‐scale effort to barcode the amphibians of the world, using the same primary barcode region of CO1, will yield important findings for science and conservation.
PERMANENT GENETIC RESOURCES: Isolation of 60 polymorphic microsatellite loci in EST libraries of four sibling species of the phytopathogenic fungal complex Microbotryum
Authors: GIRAUD T. , YOCKTENG R. , MARTHEY S. , CHIAPELLO H. , JONOT O. , LOPEZ‐VILLAVICENCIO M. , DE VIENNE D. M. , HOOD M. E. , REFREGIER G. , GENDRAULT‐JACQUEMARD A. , WINCKER P. , DOSSAT C.
Published: September 2007

We report the development of 60 microsatellite markers on four species of the fungal complex Microbotryum, causing anther smut of the Caryophyllaceae. Microsatellites were found in four expressed sequence tag (EST) libraries, built from isolates of M. lychnis‐dioicae, M. violaceum sensus stricto, M. lagerheimii and M. dianthorum, collected, respectively, from the plants Silene latifolia, S. nutans, S. vulgaris and Dianthus carthusianorum. Intrapopulation polymorphism was investigated using 24 isolates, and cross‐amplification was explored using 23 isolates belonging to at least 10 different Microbotryum species. This study provides numerous microsatellite markers for population genetics and mapping studies.
PERMANENT GENETIC RESOURCES: Isolation and characterization of microsatellite markers in the white‐faced capuchin monkey (Cebus capucinus) and cross‐species amplification in other New World monkeys
Authors: MUNIZ L. , VIGILANT L.
Published: September 2007

Seventeen polymorphic microsatellite loci were identified for white‐faced capuchin monkeys from an enriched genomic library in addition to one locus found through cross‐species comparisons. In a sample of 187 wild individuals, these loci exhibited an average of five alleles and an observed heterozygosity of 0.62. The combined probability of exclusion of a random individual from parentage was 0.99. These loci were screened in 23 other New World monkeys and an average of seven loci was variable per species, suggesting that these loci could be of use in studies of other Neotropical primates.
PERMANENT GENETIC RESOURCES: Isolation and characterization of microsatellite loci from the European corn borer, Ostrinia nubilalis (Hübner) (Insecta: Lepidoptera: Crambidae)
Authors: KIM KYUNG SEOK , COATES BRAD S. , HELLMICH RICHARD L. , SUMERFORD DOUGLAS V. , SAPPINGTON THOMAS W.
Published: September 2007

Few useful microsatellites are available for population studies of the European corn borer, Ostrinia nubilalis (Hübner). An enrichment strategy was used to develop microsatellite markers for O. nubilalis, and over 500 positive clones were isolated. Seventy‐five contained unique microsatellites, 10 of which were polymorphic with discernable polymerase chain reaction products. The 10 loci were surveyed for variability in 72 wild individuals from central Iowa. Five loci showed no deviation from Hardy–Weinberg proportions, and all were successfully cross‐amplified in the related Asian corn borer, Ostrinia furnacalis. These loci represent a significant addition to microsatellites appropriate for population studies of O. nubilalis.
PERMANENT GENETIC RESOURCES: Characterization of tri‐ and tetranucleotide microsatellite loci for the slatey‐grey snake (Stegonotus cucullatus, Colubridae)
Authors: DUBEY SYLVAIN , BROWN GREGORY P. , MADSEN THOMAS , SHINE RICHARD
Published: September 2007

We characterized nine polymorphic microsatellite (six trinucleotides and three tetranucleotides) loci for the slatey‐grey snake (Stegonotus cucullatus) from Australia, in order to study the mating system of this species. Based on a total of 100 samples, the number of alleles per locus ranged from three to 10, and the observed and expected heterozygosities ranged from 0.62 to 0.86 and from 0.53 to 0.83, respectively.
COMPUTER PROGRAMS: nessi: a program for numerical estimations in sporophytic self‐incompatibility genetic systems
Authors: BILLIARD S.
Published: September 2007

nessi is a computer program generating predictions about allelic and genotypic frequencies at the S‐locus in sporophytic self‐incompatibility systems under finite and infinite populations. For any pattern of dominance relationships among self‐incompatibility alleles, nessi computes deterministic equilibrium frequencies and estimates distributions in samples from finite populations of the number of alleles at equilibrium, allelic and genotypic frequencies at equilibrium and allelic and genotypic frequency changes in a single generation. These predictions can be used to rigorously test the impact of negative frequency‐dependent selection on diversity patterns in natural populations.
PERMANENT GENETIC RESOURCES: Ten novel polymorphic dinucleotide microsatellite loci cloned from the Antarctic fur seal Arctocephalus gazella
Authors: HOFFMAN JOSEPH I. , DASMAHAPATRA KANCHON K. , NICHOLS HAZEL J.
Published: September 2007

Ten new dinucleotide microsatellite loci were isolated from the Antarctic fur seal Arctocephalus gazella. These markers should prove useful for studying the reproductive ecology of Antarctic fur seals and other related pinniped species.
PERMANENT GENETIC RESOURCES: Development of microsatellite markers in the Japanese common squid Todarodes pacificus (Ommastrephidae)
Authors: IWATA Y. , LIAN C. L. , SAKURAI Y.
Published: September 2007

Todarodes pacificus is an important species for commercial fisheries, but its reproductive biology has been little understood. We isolated 11 polymorphic microsatellite loci from this species. These loci provided highly polymorphic microsatellite markers with four to 26 alleles per locus. The observed and expected heterozygosities ranged from 0.150 to 1.000, and from 0.660 to 0.974, respectively. These markers will be useful for research about the mating systems and genetic diversity of T. pacificus.
Increased Natural Killer Cell Cytotoxicity and IL‐2 Production in Recurrent Spontaneous Abortion
Authors: Hadinedoushan Hossein , Mirahmadian Mahroo , Aflatounian Abbas
Published: September 2007

Problem

To determine whether natural killer (NK) cells cytotoxicity in peripheral blood is altered in patients with a history of recurrent spontaneous abortion (RSA); also, if there is any correlation between cytokine production and NK cytotoxicity.

Method of study

In this case–control study, 21 patients with RSA within 24 hr of the last abortion (group I), and 32 pregnants with no history of abortion (group II) were surveyed. NK cell cytotoxicity was evaluated by flow cytometry, and IL‐2, IL‐10, transforming growth factor β1 were measured in cell culture supernatant by ELISA method.

Results

Group I showed higher NK cytotoxicity than group II at all of effector to target (E:T) ratios (P ≤ 0.045).The correlation between production of IL‐2 and NK cytotoxicity was positively significant (R = 0.350, P = 0.001). Group I had significantly higher levels of IL‐2 than group II (P = 0.001). In group II, the production of IL‐10 by peripheral blood mononuclear cells was higher than group I (P = 0.002).

Conclusion

Increased NK cell cytotoxicity and high level of IL‐2 may be considered as a risk factor for RSA.
Probing the determinants of coenzyme specificity in Peptostreptococcus asaccharolyticus glutamate dehydrogenase by site‐directed mutagenesis
Authors: Carrigan John B. , Engel Paul C.
Published: September 2007

Glutamate dehydrogenase (EC 1.4.1.2–4) from Peptostreptococcus asaccharolyticus has a strong preference for NADH over NADPH as a coenzyme, over 1000‐fold in terms of kcat/Km values. Sequence alignments across the wider family of NAD(P)‐dependent dehydrogenases might suggest that this preference is mainly due to a negatively charged glutamate at position 243 (E243) in the adenine ribose‐binding pocket. We have examined the possibility of altering coenzyme specificity of the Peptostreptococcus enzyme, and, more specifically, the role of residue 243 and neighbouring residues in coenzyme binding, by introducing a range of point mutations. Glutamate dehydrogenases are unusual among dehydrogenases in that NADPH‐specific forms usually have aspartate at this position. However, replacement of E243 with aspartate led to only a nine‐fold relaxation of the strong discrimination against NADPH. By contrast, replacement with a more positively charged lysine or arginine, as found in NADPH‐dependent members of other dehydrogenase families, allows a more than 1000‐fold shift toward NADPH, resulting in enzymes equally efficient with NADH or NADPH. Smaller shifts in the same direction were also observed in enzymes where a neighboring tryptophan, W244, was replaced by a smaller alanine (approximately six‐fold) or Asp245 was changed to lysine (32‐fold). Coenzyme binding studies confirm that the mutations result in the expected major changes in relative affinities for NADH and NADPH, and pH studies indicate that improved affinity for the extra phosphate of NADPH is the predominant reason for the increased catalytic efficiency with this coenzyme. The marked difference between the results of replacing E243 with aspartate and with positive residues implies that the mode of NADPH binding in naturally occurring NADPH‐dependent glutamate dehydrogenases differs from that adopted in E243K or E243D and in other dehydrogenases.
Rice allelopathy and the possibility for weed management
Authors: Khanh T.D. , Xuan T.D. , Chung I.M.
Published: September 2007

In attempts to control weeds in rice, much effort has been focused on rice allelopathy research for more than 30 years. Among screening methods that have been developed, some estimate the allelopathic potential of various rice cultivars in a limited time and space, which is less costly and can be conducted year round. Rice allelopathy activity is variety dependent and origin dependent, where Japonica rice shows greater allelopathic activity than Indica and Japonica–Indica hybrids. Allelopathic characteristics in rice are quantitatively inherited and several allelopathy‐involved traits have been identified. Numerous phytotoxins such as cytokinins, diterpenoids, fatty acids, flavones, glucopyranosides, indoles, momilactones (A and B), oryzalexins, phenols, phenolic acids, resorcinols and stigmastanols have been identified and determined as growth inhibitors in rice. However, the fate and actual modes of action of these compounds as well as other potent rice phytotoxins in nature are not well understood. The question of which compounds play a major role in rice allelopathy has remained obscure; however, rice allelopathy might be attributable to the interaction of all present allelochemicals. Despite locating genes determining or involving allelopathy in rice having attracted much effort, the introduction of these genes into target rice cultivars has not yet been achieved. Success in breeding new rice cultivars having good weed‐suppressing ability would benefit farmers in rice‐cultivating countries and play an important role in sustainable agricultural production.
Disentangling the effects of PAR and R:FR on lodging‐associated characters of wheat (Triticum aestivum)
Authors: Sparkes D.L. , King M.
Published: September 2007

It has been previously demonstrated that large wheat canopies are more prone to lodging than smaller canopies and it has been suggested that this is because of the plant’s response to changes in the light environment. However, it is unclear whether plants are responding to reduced light quantity (photosynthetically active radiation, PAR) or reduced light quality (red:far‐red, R:FR). Two glasshouse experiments were designed, using shading materials and supplementary light, to manipulate PAR and R:FR independently, so that the response of lodging‐associated characters of wheat could be ascribed to the different aspects of shade. The increase in lodging susceptibility associated with mutual plant shading was found to be because of both PAR and R:FR. Calculated stem failure wind speed and its component traits responded to shading entirely through their response to reductions in PAR. Ear number, which led to differences in plant leverage, was also explained by differences in PAR. In contrast, calculated anchorage failure wind speed and rooting traits demonstrated additional responses to R:FR, over and above those to PAR. Thus, the aspect of mutual plant shading responsible for increased lodging susceptibility of wheat varied between stem and root traits. PAR was solely responsible for changes in stem traits associated with lodging but R:FR played a role in determining rooting traits that affect the anchorage capacity of wheat plants.
Neutral hydrogen in galactic fountains
Authors: Booth C. M. , Theuns Tom
Published: September 2007

Simulations of an isolated Milky Way-like galaxy, in which supernovae power a galactic fountain, reproduce the observed velocity and 21-cm brightness statistics of galactic neutral hydrogen (Hi). The simulated galaxy consists of a thin Hi disc, similar in extent and brightness to that observed in the Milky Way, and extra-planar neutral gas at a range of velocities due to the galactic fountain. Mock observations of the neutral gas resemble the Hi flux measurements from the Leiden–Argentine–Bonn Hisurvey, including a high-velocity tail which matches well with observations of high-velocity clouds. The simulated high-velocity clouds are typically found close to the galactic disc, with a typical line-of-sight distance of 13 kpc from observers on the solar circle. The fountain efficiently cycles matter from the centre of the galaxy to its outskirts at a rate of around 0.5M⊙yr−1.
Galaxy merging in modified Newtonian dynamics
Authors: Nipoti Carlo , Londrillo Pasquale , Ciotti Luca
Published: September 2007

We present the results of N-body simulations of dissipationless galaxy merging in modified Newtonian dynamics (MOND). For comparison, we also studied Newtonian merging between galaxies embedded in dark matter haloes, with internal dynamics equivalent to the MOND systems. We found that the merging time-scales are significantly longer in MOND than in Newtonian gravity with dark matter, suggesting that observational evidence of rapid merging could be difficult to explain in MOND. However, when two galaxies eventually merge, the MOND merging end-product is hardly distinguishable from the final stellar distribution of an equivalent Newtonian merger with dark matter.
Measurement of the intensity profile of a Gaussian laser beam near its focus using an optical fiber
Authors: Sheu Fang-Wen , Chang Ching-Huang
Published: September 2007

We have designed a new pinhole-scan system to measure the Gaussian intensity distribution of a He-Ne laser beam that passes through a series of lenses. Our detection device uses a single-mode optical fiber as the so-called pinhole. One side of the optical fiber is fixed on the top of a motorized translation stage to capture the laser light, and the other side is connected to an optical power meter. A digital oscilloscope is used to observe the detected light intensity. When the translation stage as well as the fiber tip is moved across the laser beam, the oscilloscope displays the scanned trace of the laser beam intensity. The evolution of the intensity distribution of a focused laser beam is measured and then fitted to distributions predicted from Gaussian optics. The measured beam waist size is compared with the result of Gaussian-beam q-parameter analysis. Using this simple system we can easily observe the transverse intensity profile of a Gaussian laser beam in the (1+1)-dimensional plane in the vicinity of the focus.
Measurement of the dispersion relation of capillary waves by laser diffraction
Authors: Zhu Feng , Miao Runcai , Xu Chunlong , Cao Zanzan
Published: September 2007

We describe a simple method for generating capillary waves of a known frequency on a liquid surface. A noncontact technique based on laser diffraction is introduced to measure the wavelength of the capillary waves with great precision. The data give the dispersion relation of capillary waves and provide an accurate method for determining the relation between the surface tension and the temperature in a nondestructive way.
Determination of the diffusion coefficient between corn syrup and distilled water using a digital camera
Authors: Ray E. , Bunton P. , Pojman J. A.
Published: September 2007

A simple technique for determining the diffusion coefficient between two miscible liquids is presented based on observing concentration-dependent ultraviolet-excited fluorescence using a digital camera. The ultraviolet-excited visible fluorescence of corn syrup is proportional to the concentration of the syrup. The variation of fluorescence with distance from the transition zone between the fluids is fit by the Fick’s law solution to the diffusion equation. By monitoring the concentration at successive times, the diffusion coefficient can be determined in otherwise transparent materials. The technique is quantitative and makes measurement of diffusion accessible in the advanced undergraduate physics laboratory.
Foucault pendulum through basic geometry
Authors: von Bergmann Jens , von Bergmann HsingChi
Published: September 2007

We provide a thorough explanation of the Foucault pendulum that utilizes its underlying geometry on a level suitable for science students not necessarily familiar with calculus. We also explain how the geometrically understood Foucault pendulum can serve as a prototype for more advanced phenomena in physics known as Berry’s phase or geometric phases.
Revisiting Hafemeister’s science and society tests
Authors: Brecha R. J. , Berney R. , Craver B.
Published: September 2007

We revisit a series of papers on science and society issues by David Hafemeister in the 1970s and 1980s. The emphasis in the present work is on world oil production limits and some consequences of various possible scenarios for the near future. Some of the data and scenarios used by Hafemeister are updated for U.S. oil production in the past two decades, and extended to an analysis of a peak in world oil production in the future. We discuss some simple scenarios for future energy use patterns and look at the consequence of these scenarios as world oil production begins to decline. We also provide a list of resources for critical investigations of natural resource extraction and depletion patterns.
The Carnot engine based on the small thermodynamic system: Its efficiency and the ergodic hypothesis
Authors: Bormashenko Edward , Shkorbatov Alexander , Gendelman Oleg
Published: September 2007

The operation of the minimal Carnot engine is discussed. It is demonstrated that its efficiency is given by the traditional Carnot expression when the motion of the gas particles is temporally averaged (instead of the usual spatial averaging). The impact of the heat capacity of the apparatus elements on the efficiency is considered, and the influence of temperature fluctuations on the engine operation is considered. The parameters of the minimal Carnot engine are calculated.
Modeling protein synthesis from a physicist’s perspective: A toy model
Authors: Basu Aakash , Chowdhury Debashish
Published: September 2007

Proteins are polymers of amino acids. These macromolecules are synthesized by intracellular machines called ribosomes. Although the experimental investigation of protein synthesis has been a traditional area of research in molecular cell biology, important quantitative models of protein synthesis have been reported in research journals devoted to statistical physics and related interdisciplinary topics. From the perspective of a physicist, protein synthesis is the classical transport of interacting ribosomes on a messenger RNA (mRNA) template that dictates the sequence of the amino acids on the protein. We discuss appropriate simplification of the models and methods. In particular, we develop and analyze a simple toy model using some elementary techniques of nonequilibrium statistical mechanics and predict the average rate of protein synthesis and the spatial organization of the ribosomes in the steady state.
Plastic bottle oscillator: Rhythmicity and mode bifurcation of fluid flow
Authors: Kohira Masahiro I. , Magome Nobuyuki , Kitahata Hiroyuki , Yoshikawa Kenichi
Published: September 2007

The oscillatory flow of water draining from an upside-down plastic bottle with a thin pipe attached to its head is studied as an example of a dissipative structure generated under far-from-equilibrium conditions. Mode bifurcation was observed in the water/air flow: no flow, oscillatory flow, and counter flow were found when the inner diameter of the thin pipe was changed. The modes are stable against perturbations. A coupled two-bottle system exhibits either in-phase or anti-phase self-synchronization. These characteristic behaviors imply that the essential features of the oscillatory flow in a single bottle system can be described as a limit-cycle oscillation.
Pharmacokinetics of Acyclovir after Intravenous Infusion of Acyclovir and after Oral Administration of Acyclovir and Its Prodrug Valacyclovir in Healthy Adult Horses
Authors: Garré B. , Shebany K. , Gryspeerdt A. , Baert K. , van der Meulen K. , Nauwynck H. , Deprez P. , De Backer P. , Croubels S.
Published: September 2007

The purpose of this study was twofold. The first aim was to evaluate the oral bioavailability and pharmacokinetics (PKs) of acyclovir in horses after intravenous (i.v.) administration and after oral administration of acyclovir and its prodrug, valacyclovir. Second, we aimed to combine these PK data with pharmacodynamic (PD) information, i.e., 50% effective concentrations (EC50values) from in vitro studies, to design an optimal dosage schedule. Three treatments were administered to healthy adult horses: 10 mg of acyclovir/kg of body weight delivered as an i.v. infusion over 1 h, 20 mg of acyclovir/kg administered as tablets by nasogastric intubation, and 20 mg of valacyclovir/kg administered as tablets by nasogastric intubation. Total plasma concentrations were measured by a high-performance liquid chromatography method combined with fluorescence detection, while unbound plasma concentrations were determined by liquid chromatography-tandem mass spectrometry. The peak concentration of i.v. acyclovir was approximately 10 μg/ml for both the total and the unbound plasma concentrations. The mean half-life of elimination was between 5.05 h (total concentration) and 11.9 h (unbound concentration). Oral administration of acyclovir resulted in low maximum concentration in plasma (Cmax) and poor bioavailability. A 10-times-higherCmaxand an 8-times-higher bioavailability were achieved with oral administration of valacyclovir. The i.v. administration of 10 mg/kg acyclovir and the oral administration of 20 mg/kg valacyclovir achieved concentrations within the sensitivity range of equine herpesvirus type 1 (EHV-1). The higher bioavailability of valacyclovir makes it an attractive candidate for the prophylactic and/or therapeutic treatment of horses infected with EHV-1. The results from the PK/PD modeling showed that a dosage of 40 mg/kg valacyclovir, administered three times daily, would be sufficient to reach plasma concentrations above the EC50values.
Lack of Correlation betweenembBMutation and Ethambutol MIC inMycobacterium tuberculosisClinical Isolates from China
Authors: Shi Ruiru , Zhang Jianyuan , Otomo Koji , Zhang Guolong , Sugawara Isamu
Published: September 2007

Seventy-fourMycobacterium tuberculosisclinical isolates from China were subjected to drug susceptibility testing using ethambutol, isoniazid, rifampin, and ofloxacin. The results revealed that the presence ofembBmutations did not correlate with ethambutol resistance but was associated with multiple-drug resistance, especially resistance to both ethambutol and rifampin.
Clinical and Pharmacological Determinants of the Therapeutic Response to Dihydroartemisinin-Piperaquine for Drug-Resistant Malaria
Authors: Price R. N. , Hasugian A. R. , Ratcliff A. , Siswantoro H. , Purba H. L. E. , Kenangalem E. , Lindegardh N. , Penttinen P. , Laihad F. , Ebsworth E. P. , Anstey N. M. , Tjitra E.
Published: September 2007

Dihydroartemisinin-piperaquine (DHP) is an important new treatment for drug-resistant malaria, although pharmacokinetic studies on the combination are limited. In Papua, Indonesia, we assessed determinants of the therapeutic efficacy of DHP for uncomplicated malaria. Plasma piperaquine concentrations were measured on day 7 and day 28, and the cumulative risk of parasitological failure at day 42 was calculated using survival analysis. Of the 598 patients in the evaluable population 342 had infections with
Plasmodium falciparum
, 83 with
Plasmodium vivax
, and 173 with a mixture of both species. The unadjusted cumulative risks of recurrence were 7.0% (95% confidence interval [CI]: 4.6 to 9.4%) for
P. falciparum
and 8.9% (95% CI: 6.0 to 12%) for
P. vivax
. After correcting for reinfections the risk of recrudescence with
P. falciparum
was 1.1% (95% CI: 0.1 to 2.1%). The major determinant of parasitological failure was the plasma piperaquine concentration. A concentration below 30 ng/ml on day 7 was observed in 38% (21/56) of children less than 15 years old and 22% (31/140) of adults (
P
= 0.04), even though the overall dose (mg per kg of body weight) in children was 9% higher than that in adults (
P
< 0.001). Patients with piperaquine levels below 30 ng/ml were more likely to have a recurrence with
P. falciparum
(hazard ratio [HR] = 6.6 [95% CI: 1.9 to 23];
P
= 0.003) or
P. vivax
(HR = 9.0 [95% CI: 2.3 to 35];
P
= 0.001). The plasma concentration of piperaquine on day 7 was the major determinant of the therapeutic response to DHP. Lower plasma piperaquine concentrations and higher failure rates in children suggest that dose revision may be warranted in this age group.
Molecular and Biochemical Characterization of the Chromosome-Encoded Class A β-Lactamase BCL-1 from
Bacillus clausii
Authors: Girlich Delphine , Leclercq Roland , Naas Thierry , Nordmann Patrice
Published: September 2007

A chromosomal β-lactamase gene from
Bacillus clausii
NR, which is used as a probiotic, was cloned and expressed in
Escherichia coli
. It encodes a clavulanic acid-susceptible Ambler class A β-lactamase, BCL-1, with a pI of 5.5 and a molecular mass of ca. 32 kDa. It shares 91% and 62% amino acid identity with the chromosomally encoded PenP penicillinases from
B. clausii
KSM-K16 and
Bacillus licheniformis
, respectively. The hydrolytic profile of this β-lactamase includes penicillins, narrow-spectrum cephalosporins, and cefpirome. This chromosome-encoded enzyme was inducible in
B. clausii
, and its gene is likely related to upstream-located regulatory genes that share significant identity with those reported to be upstream of the penicillinase gene of
B. licheniformis
. The
bla
BCL-1
gene was located next to the known chromosomal
aadD2
gene and the
erm34
gene, which encode resistance to aminoglycosides and macrolides, respectively. Similar genes were found in a collection of
B. clausii
reference strains.
Antimicrobial Effect of Halocidin-Derived Peptide in a Mouse Model ofListeriaInfection
Authors: Jang Woong Sik , Lee Sang-Chul , Lee Young Shin , Shin Yong Pyo , Shin Kyoung Hwa , Sung Boo Hee , Kim Byung S. , Lee Soo Han , Lee In Hee
Published: September 2007

Halocidin is an antimicrobial peptide found in the tunicate. A series of experiments were previously conducted in an attempt to develop a novel antibiotic derived from halocidin, as the peptide was determined to evidence profound antimicrobial activity against a variety of antibiotic-resistant microbes, with significantly less toxicity to human blood cells. In this study, we assessed the validity of one of the halocidin congeners, called Khal, as a new antibiotic for the treatment of systemic bacterial infections. Our in vitro antimicrobial tests showed that the MICs of Khal against several gram-positive bacteria were below 16 μg/ml in the presence of salt. We also determined that Khal retained sufficient target selectivity to discern microbial and human blood cells and was therefore capable of efficiently killing invading pathogens. Furthermore, Khal caused no aggregation problems upon incubation with human serum and also proved to be resistant to proteolysis by enzymes occurring in human serum. In the following experiments conducted with a mouse model ofListeria monocytogenesinfection, we demonstrated that a single intravenous inoculation with Khal resulted in significant therapeutic effects on the survival of mice. In addition, our bacterial-enumeration analysis showed that afterListeriainfection, livers and spleens from Khal-treated mice generated a great deal fewer recoverable CFU. Finally, the antibiotic effects of Khal were evaluated under confocal microscopy after we immunostained the liver sections with anti-Khal antibody. It was concluded that Khal bound specifically to the surfaces of bacteria colonized in the mouse liver and killed the bacteria rapidly.
Emergence of the Quinolone Resistance-Mediating Gene
aac(6′)-Ib-cr
in Extended-Spectrum-β-Lactamase-Producing
Klebsiella
Isolates Collected in Slovenia between 2000 and 2005
Authors: Ambrožič Avguštin Jerneja , Keber Rok , Žerjavič Katja , Oražem Toni , Grabnar Miklavž
Published: September 2007

Seventy-four nonrepetitive uropathogenic fluoroquinolone-resistant or -intermediate extended-spectrum-β-lactamase-producing
Klebsiella
isolates from Slovenia were screened for the presence of plasmid-mediated quinolone resistance genes. None of the known
qnr
genes were detected. The
aac(6′)-Ib-cr
allele was detected on plasmids from 25 transconjugants for which the ciprofloxacin MIC was higher than for the recipient
Escherichia coli
strain.
Presentation ofToxoplasma gondiiAntigens via the Endogenous Major Histocompatibility Complex Class I Pathway in Nonprofessional and Professional Antigen-Presenting Cells
Authors: Dzierszinski Florence , Pepper Marion , Stumhofer Jason S. , LaRosa David F. , Wilson Emma H. , Turka Laurence A. , Halonen Sandra K. , Hunter Christopher A. , Roos David S.
Published: September 2007

Challenge with the intracellular protozoan parasiteToxoplasma gondiiinduces a potent CD8+T-cell response that is required for resistance to infection, but many questions remain about the factors that regulate the presentation of major histocompatibility complex class I (MHC-I)-restricted parasite antigens and about the role of professional and nonprofessional accessory cells. In order to address these issues, transgenic parasites expressing ovalbumin (OVA), reagents that track OVA/MHC-I presentation, and OVA-specific CD8+T cells were exploited to compare the abilities of different infected cell types to stimulate CD8+T cells and to define the factors that contribute to antigen processing. These studies reveal that a variety of infected cell types, including hematopoietic and nonhematopoietic cells, are capable of activating an OVA-specific CD8+T-cell hybridoma, and that this phenomenon is dependent on the transporter associated with antigen processing and requires liveT. gondii. Several experimental approaches indicate that T-cell activation is a consequence of direct presentation by infected host cells rather than cross-presentation. Surprisingly, nonprofessional antigen-presenting cells (APCs) were at least as efficient as dendritic cells at activating this MHC-I-restricted response. Studies to assess whether these cells are involved in initiation of the CD8+T-cell response toT. gondiiin vivo show that chimeric mice expressing MHC-I only in nonhematopoietic compartments are able to activate OVA-specific CD8+T cells upon challenge. These findings associate nonprofessional APCs with the initial activation of CD8+T cells during toxoplasmosis.
Iodine/Toluenesulfonic Acid: A Novel Catalyst for Isopropylidenation in Carbohydrate Chemistry
Authors: Zhao Guilong , Zhang Yan , Wang Jianwu
Published: September 2007

A novel catalyst for O-isopropylidenation of carbohydrates, a mixture of toluenesulfonic acid and iodine, was developed.
5-Cinnamoyl- and 5-(Ethoxycarbonyl)-6-styryl Derivatives of 4-Aryl-3,4-dihydropyrimidin-2(1H)-ones
Authors: Kolosov Maksim A. , Orlov Valeriy D. , Vashchenko Valeriy V. , Shishkina Svetlana V. , Shishkin Oleg V.
Published: September 2007

Several 5-cinnamoyl- and 5-(ethoxycarbonyl)-6-styryl derivatives of 4-aryl-3,4-dihydropyrimidin-2(1H)-ones were obtained and their physicochemical properties were investigated. The introduction of alkyl substituent in position 1 of dihydropyrimidine ring was shown to promote the Claisen-Schmidt reaction on acetyl group only; without the alkyl both acetyl and 6-methyl groups participate in the reaction.
DELAYED FUZZY CONTROLLER DESIGN FOR HYPERCHAOS WITH APPLICATION TO HYPERCHAOTIC CHEN'S SYSTEM
Authors: LIU XINGWEN , GAO XIN
Published: September 2007

Studied in this paper is the control problem of hyperchaotic systems. By combining Takagi–Sugeno (T–S) fuzzy model with parallel distributed compensation design technique, we propose a delay-dependent control criterion via pure delayed state feedback. Because the result is expressed in terms of linear matrix inequalities (LMIs), it is quite convenient to check in practice. Based on this criterion, a procedure is provided for designing fuzzy controller for such systems. This method is a universal one for controlling continuous hyperchaotic systems. As illustrated by its application to hyperchaotic Chen's system, the controller design is quite effective.
SOCIAL DILEMMAS AND COOPERATION IN COMPLEX NETWORKS
Authors: TOMASSINI MARCO , PESTELACCI ENEA , LUTHI LESLIE
Published: September 2007

In this paper we extend the investigation of cooperation in some classical evolutionary games on populations where the network of interactions among individuals is of the scale-free type. We show that the update rule, the payoff computation and, to some extent the timing of the operations, have a marked influence on the transient dynamics and on the amount of cooperation that can be established at equilibrium. We also study the dynamical behavior of the populations and their evolutionary stability.
ON THE Σ0→Λ0 TRANSITION MAGNETIC MOMENT IN THE EFFECTIVE QUARK MODEL WITH CHIRAL SYMMETRY
Authors: YA. BERDNIKOV A. , BERDNIKOV YA. A. , IVANOV A. N. , IVANOVA V. A. , NIKITCHENKO A. V. , TROITSKAYA N. I.
Published: September 2007

We calculate the Σ0→Λ0 transition magnetic moment μΣ0Λ0 in the effective quark model with chiral U (3) × U (3) symmetry.5 We find that the dominant contribution is proportional to the quark condensate that indicates the important role of spontaneous breaking of chiral symmetry for its formation. Our result μΣ0Λ0 = -1.62 μN, where μN is a nuclear magneton, agrees well with the experimental data [Formula: see text]. It also agrees well both quantitatively and qualitatively with the result, obtained in the QCD sum rules approach |μΣ0Λ0| = (1.60±0.30)μN,3 where the dominant contribution is proportional to the quark condensate as well.
SPACE SYMMETRIES AND QUANTUM BEHAVIOR OF FINITE ENERGY CONFIGURATIONS IN SU(2)-GAUGE THEORY
Authors: SHURGAIA A. V. , MÜLLER-KIRSTEN H. J. W.
Published: September 2007

The quantum properties of localized finite energy solutions to classical Euler–Lagrange equations are investigated using the method of collective coordinates. The perturbation theory in terms of inverse powers of the coupling constant g is constructed, taking into account the conservation laws of momentum and angular momentum (invariance of the action with respect to the group of motion M(3) of three-dimensional Euclidean space) rigorously in every order of perturbation theory.
GLOBAL EXPONENTIAL STABILITY OF CLASSICAL SOLUTIONS TO THE HYDRODYNAMIC MODEL FOR SEMICONDUCTORS
Authors: FANG DAOYUAN , XU JIANG , ZHANG TING
Published: September 2007

In this paper, the global well-posedness and stability of classical solutions to the multidimensional hydrodynamic model for semiconductors on the framework of Besov space are considered. We weaken the regularity requirement of the initial data, and improve some known results in Sobolev space. The local existence of classical solutions to the Cauchy problem is obtained by the regularized means and compactness argument. Using the high- and low-frequency decomposition method, we prove the global exponential stability of classical solutions (close to equilibrium). Furthermore, it is also shown that the vorticity decays to zero exponentially in the 2D and 3D space. The main analytic tools are the Littlewood–Paley decomposition and Bony's para-product formula.
A BICHARACTERISTICS METHOD FOR ADAPTIVE MODELING OF TRANSIENT WAVE PROPAGATION IN UNBOUNDED ACOUSTIC MEDIA
Authors: PARK SI-HWAN
Published: September 2007

A computational procedure is developed for adaptive modeling of transient wave propagation in an unbounded acoustic layer. The adaptivity herein is concerned with controlling the error caused by imperfect modeling of unbounded domains, and the procedure aims at determining the optimal order of the absorbing boundary condition (ABC) under consideration to control the error in the solution within a predetermined tolerance. The perfectly matched layer (PML) is used as an ABC, and the size of the PML domain controls the error associated with modeling unbounded domains. As a key technique in the adaptive method, a local solution procedure is designed based on the method of bicharacteristics to extract, from the computed solution, the information flowing into the computational domain. Numerical experiments show that, under wide circumstances, the maximum pressure associated with the inflow evaluated near the truncated boundary of the PML domain can be related with the maximum error in the pressure and thus can be used as an error estimator. It is demonstrated that a simple adaptive algorithm based on this error estimator can automatically determine the PML domain size to produce solutions with controlled errors.
SCREEN CONFORMAL SUBMERSIONS BETWEEN LIGHTLIKE MANIFOLDS AND SEMI-RIEMANNIAN MANIFOLDS AND THEIR HARMONICITY
Authors: SAHIN BAYRAM
Published: September 2007

In this paper, we introduce a new submersion ϕ : M → N, namely screen conformal submersion, between a lightlike manifold M and a semi-Riemann manifold N. We give examples and show that the lightlike manifold M is shear free under a condition if ϕ : M → N is a screen conformal submersion. Also we define special screen submersions: radical and screen homothetic submersions. We obtain that the radical homothetic submersion ϕ : M → N implies that M is a Reinhart lightlike manifold. Moreover we define and study the lightlike versions of O'Neill's tensors for a horizontally conformal submersion and show that these tensors have different properties from the Riemannian case. Using these tensors, we investigate the relationships between the curvatures of base and total manifolds. Finally, since the trace of a smooth mapping is not meaningful on the radical part of a lightlike manifold, we introduce lightlike harmonic map between lightlike manifolds and semi-Riemannian manifolds, supported by an example. We also give a characterization for a screen conformal submersion to be lightlike harmonic.
ON THE MAGIC MATRIX BY MAKHLIN AND THE B-C-H FORMULA IN SO(4)
Authors: FUJII KAZUYUKI , SUZUKI TATSUO
Published: September 2007

A closed expression to the Baker–Campbell–Hausdorff (B-C-H) formula in SO(4) is given by making use of the magic matrix by Makhlin. As far as we know this is the first nontrivial example on (semi–) simple Lie groups summing up all terms in the B-C-H expansion.
Asthma Genetics: From Linear to Multifactorial Approaches
Authors: Guerra Stefano , Martinez Fernando D.
Published: September 2007

Asthma risk has a clear hereditary component but, unexpectedly, the majority of reported associations between genetic variants and asthma have not been consistently replicated across studies. Methodological flaws have been indicated as a possible explanation for these inconsistencies. However, an alternative explanation is that the effects of genetic variants depend on other factors whose frequency and distribution vary, both across individuals and across populations. Within this framework, we review recent advances in asthma genetics and conclude that a paradigm shift is needed, because a static model in which the DNA sequence is associated with disease risk in a linear fashion fails to consider the interdependence of the diverse components of asthma risk. We propose an integrated approach, linking sequence variation to specific phenotypic manifestations of the disease by taking into account concurrent influences from biological systems and environmental factors that interact within specific developmental windows of opportunity.
The Effect of Toll-Like Receptors and Toll-Like Receptor Genetics in Human Disease
Authors: Garantziotis Stavros , Hollingsworth John W , Zaas Aimee K. , Schwartz David A.
Published: September 2007

Toll-like receptors (TLRs) enable innate immune recognition of endogenous and exogenous prototypic ligands. They also orchestrate innate and adaptive immune response to infection, inflammation, and tissue injury. Given their significance in the immune response, it is not surprising that genetic variations of TLRs can affect their function and by extension affect the response of the organism to environmental stimuli. The genetics of TLRs provides important insights in gene-environment interactions in health and disease, and it may enable scientists to assess patients’ susceptibility to diseases or predict their response to treatments.