bluuebunny/crossref_metadata_2025 huggingface dataset:
Mailed urine samples are not an effective screening approach for Chlamydia trachomatis case finding among young men
Authors: Domeika M , Oscarsson L , Hallén A , Hjelm E , Sylvan S
Published: January 2007

Background  Frequency of testing is known to be low for sexually transmitted infections (STIs) in men aged 20–24 years. The use of mailed, home‐obtained urine specimens could increase the uptake of young men and facilitate screening programmes for the detection of asymptomatic Chlamydia trachomatis.

Objective  The aim of the present study is to evaluate the home screening approach as a tool for recruitment of asymptomatic men for screening of genital C. trachomatis infections.

Methods  Men aged 19–24 years old (n = 1936) were invited to participate in home‐based testing for genital C. trachomatis infection. Persons who agreed to be tested were provided with a testing kit. Self‐collected first void urine was sent for testing to the microbiology laboratory. The test result was accessible on the study's web‐page 1 week after testing. Individuals with a diagnosed infection were instructed to contact the venereal disease department.

Results  The response rate was 24% (462/1936). The responders’ main reason for not participating was a feeling of being safe regarding STIs (87%; 159/182). The primary reason for this feeling of safety was that the responders were in a steady relationship (59%; 107/159). Having sex outside a steady relationship was reported by 36% (90/250) of the responders. The prevalence of C. trachomatis infection among the responders was 2.02% and the reported history of chlamydial infection was 36% (34/95). Out of the responders, 92% (229/249) were, to varying degrees, concerned about getting STIs; however, the majority (72%; 174/242) estimated the risk to be low.

Conclusion  Home screening using web‐based answer management is a feasible tool for STI screening, which lowers the threshold for people at risk. In this particular population, however, the response rate was too low to be routinely introduced.
Modulation of P‐glycoprotein function by sphingosine kinase‐1 in brain endothelial cells
Authors: Pilorget Anthony , Demeule Michel , Barakat Stéphane , Marvaldi Jacques , Luis José , Béliveau Richard
Published: January 2007

P‐glycoprotein (P‐gp), an ABC‐transporter highly expressed in brain capillaries, protects the brain by extruding xenobiotics. However, its overexpression has also been associated with the multidrug resistance phenotype in tumors. Here, we have investigated the regulation of P‐gp transport activity by sphingosine kinase 1 (SphK‐1) in brain endothelial cells. We first demonstrated that SphK‐1 is overexpressed in endothelial cells (EC) isolated from rat brain tumors compared with EC from normal brain. We also provide evidence that the overexpression of SphK‐1 in the cerebral EC line RBE4 leads to the up‐regulation of P‐gp, both at the gene and protein levels, and that this modulation depends on the catalytic activity of SphK‐1. Moreover, we determined the effect of sphingosine‐1‐phosphate (S1P), the product of SphK‐1, on P‐gp function. S1P strongly stimulates P‐gp transport activity, without modulating its expression. Finally, we found that the S1P‐mediated stimulation of P‐gp activity is mediated by S1P‐1 and S1P‐3 receptors at the RBE4 cell surface. Altogether, these results indicate that SphK‐1 and its product S1P are involved in the control of P‐gp activity in RBE4 cells. Since SphK‐1 is overexpressed in EC from brain tumors, these data also suggest that this kinase and its product could contribute to the acquisition and the maintenance of the multidrug resistance phenotype in brain tumor‐derived endothelial cells.
Neuroprotective role of bradykinin because of the attenuation of pro‐inflammatory cytokine release from activated microglia
Authors: Noda Mami , Kariura Yukihiro , Pannasch Ulrike , Nishikawa Kaori , Wang Liping , Seike Toshihiro , Ifuku Masataka , Kosai Yuki , Wang Bing , Nolte Christiane , Aoki Shunsuke , Kettenmann Helmut , Wada Keiji
Published: January 2007

Bradykinin (BK) has been reported to be a mediator of brain damage in acute insults. Receptors for BK have been identified on microglia, the pathologic sensors of the brain. Here, we report that BK attenuated lipopolysaccharide (LPS)‐induced release of tumor necrosis factor‐alpha (TNF‐α) and interleukin‐1β from microglial cells, thus acting as an anti‐inflammatory mediator in the brain. This effect was mimicked by raising intracellular cAMP or stimulating the prostanoid receptors EP2 and EP4, while it was abolished by a cAMP antagonist, a prostanoid receptor antagonist, or by an inhibitor of the inducible cyclooxygenase (cyclooxygenase‐2). BK also enhanced formation of prostaglandin E2and expression of microsomal prostaglandin E synthase. Expression of BK receptors and EP2/EP4 receptors were also enhanced. Using physiological techniques, we identified functional BK receptors not only in culture, but also in microglia from acute brain slices. BK reduced LPS‐induced neuronal death in neuron–microglia co‐cultures. This was probably mediated via microglia as it did not affect TNF‐α‐induced neuronal death in pure neuronal cultures. Our data imply that BK has anti‐inflammatory and neuroprotective effects in the central nervous system by modulating microglial function.
Neuronal NOS‐mediated nitration and inactivation of manganese superoxide dismutase in brain after experimental and human brain injury
Authors: Bayır Hülya , Kagan Valerian E. , Clark Robert S. B. , Janesko‐Feldman Keri , Rafikov Ruslan , Huang Zhentai , Zhang Xiaojing , Vagni Vincent , Billiar Timothy R. , Kochanek Patrick M.
Published: January 2007

Manganese superoxide dismutase (MnSOD) provides the first line of defense against superoxide generated in mitochondria. SOD competes with nitric oxide for reaction with superoxide and prevents generation of peroxynitrite, a potent oxidant that can modify proteins to form 3‐nitrotyrosine. Thus, sufficient amounts of catalytically competent MnSOD are required to prevent mitochondrial damage. Increased nitrotyrosine immunoreactivity has been reported after traumatic brain injury (TBI); however, the specific protein targets containing modified tyrosine residues and functional consequence of this modification have not been identified. In this study, we show that MnSOD is a target of tyrosine nitration that is associated with a decrease in its enzymatic activity after TBI in mice. Similar findings were obtained in temporal lobe cortical samples obtained from TBI cases versus control patients who died of causes not related to CNS trauma. Increased nitrotyrosine immunoreactivity was detected at 2 h and 24 h versus 72 h after experimental TBI and co‐localized with the neuronal marker NeuN. Inhibition and/or genetic deficiency of neuronal nitric oxide synthase (nNOS) but not endothelial nitric oxide synthase (eNOS) attenuated MnSOD nitration after TBI. At 24 h after TBI, there was predominantly polymorphonuclear leukocytes accumulation in mouse brain whereas macrophages were the predominant inflammatory cell type at 72 h after injury. However, a selective inhibitor or genetic deficiency of inducible nitric oxide synthase (iNOS) failed to affect MnSOD nitration. Nitration of MnSOD is a likely consequence of peroxynitrite within the intracellular milieu of neurons after TBI. Nitration and inactivation of MnSOD could lead to self‐amplification of oxidative stress in the brain progressively enhancing peroxynitrite production and secondary damage.
Regulation of GTP cyclohydrolase I expression by orphan receptor Nurr1 in cell culture andin vivo
Authors: Gil Minchan , McKinney Cushla , Lee Mi Kyeong , Eells Jeffrey B. , Phyillaier Marcia A. , Nikodem Vera M.
Published: January 2007

Nurr1 is an orphan nuclear transcription factor essential for the terminal differentiation of dopamine (DA) neurons in the ventral midbrain (VM). To identify the Nurr1‐target genes, we carried out microarray and quantitative real‐time PCR analyses of Nurr1 null and wild‐type mice in VM at embryonic day (E) 12.5 and shortly after birth (P0). In addition to the absence of mRNAs of DA synthesizing enzymes, the guanosine 5′‐triphosphate (GTP) cyclohydrolase I (GTPCH) was also substantially reduced in the VM of Nurr1‐null mice. GTPCH is the first enzyme in the synthesis pathway of tetrahydrobiopterin (BH4), an essential cofactor for tyrosine hydroxylase in DA synthesis. In the mouse, Nurr1 and GTPCH mRNA were first detected at E10.5, and GTPCH transcription paralleled that of Nurr1. Small interfering RNA targeted against Nurr1 decreases GTPCH expression in MC3T3‐E1 osteoblasts in cell culture. Cotransfection of Nurr1 and the GTPCH‐luciferase (luc) reporter increased the luc activity by about threefold in N2A cells. Additional analysis using 5′‐deletions and mutants revealed that Nurr1 activates GTPCH transcription indirectly through the proximal promoter region, in the absence of the nerve growth factor‐induced clone B (NGFI‐B) responsive element‐like sites, similarly, as recently reported for DA transporter regulation by Nurr1.
Metabotropic glutamate receptor 3 protects neurons from glucose‐induced oxidative injury by increasing intracellular glutathione concentration
Authors: Berent‐Spillson Alison , Russell James W.
Published: January 2007

High glucose concentrations cause oxidative injury and programmed cell death in neurons, and can lead to diabetic neuropathy. Activating the type 3 metabotropic glutamate receptor (mGluR3) prevents glucose‐induced oxidative injury in dorsal root ganglion neurons co‐cultured with Schwann cells. To determine the mechanisms of protection, studies were performed in rat dorsal root ganglion neuron–Schwann cell co‐cultures. The mGluR3 agonist 2R,4R‐4‐aminopyrrolidine‐2,4‐dicarboxylate prevented glucose‐induced inner mitochondrial membrane depolarization, reactive oxygen species accumulation, and programmed cell death, and increased glutathione (GSH) concentration in co‐cultured neurons and Schwann cells, but not in neurons cultured without Schwann cells. Protection was diminished in neurons treated with the GSH synthesis inhibitor l‐buthionine‐sulfoximine, suggesting that mGluR‐mediated protection requires GSH synthesis. GSH precursors and the GSH precursor GSH‐ethyl ester also protected neurons from glucose‐induced injury, indicating that GSH synthesis in Schwann cells, and transport of reaction precursors to neurons, may underlie mGluR‐mediated neuroprotection. These results support the conclusions that activating glial mGluR3 protects neurons from glucose‐induced oxidative injury by increasing free radical scavenging and stabilizing mitochondrial function, through increased GSH antioxidant defense.
Use of a novel water‐soluble arylating agent to dye wool and wool blends with disperse dyes
Authors: Broadbent P J , Clark M , Croft S N , Lewis D M
Published: January 2007

A series of water‐soluble fibre‐reactive arylating agents were synthesised and evaluated from the stand‐point of improving fibre coloration with disperse dyes. In particular, the compound, sodio‐2,4‐dianilino‐6‐[4′‐β‐sulphatoethylsulphonylanilino]‐s‐triazine (FAA 200) was found to be promising; this compound could be applied in the same bath as a disperse dye at pH 5–6. Under the latter conditions this compound showed high substantivity to wool and at the boil readily underwent β‐elimination of the sulphate ester residue to give the vinyl sulphone reactive group which adds on to nucleophilic sites in the fibre to form a covalent bond. Coapplication with commercially available disperse dyes gave bright, level dyeings that exhibited promising wet fastness. FAA 200 was used as an auxiliary to dye disperse dyes on both fibre components of a wool–polyester blend fabric; it was found that addition of hydrogen peroxide or sodium thiocyanate was necessary to obviate reduction of certain disperse dyes when dyeing at 120 °C.
Synthesis and mutagenic properties of 4,4′‐diamino‐p‐terphenyl and 4,4′‐diamino‐p‐quaterphenyl
Authors: Wang Jinlong , Freeman Harold S , Claxton Larry D
Published: January 2007

4,4′‐Diamino‐p‐terphenyl and 4,4′‐diamino‐p‐quaterphenyl were synthesised from readily available chemical intermediates. These compounds, along with 1,4‐diaminophenylene and benzidine were examined in the Salmonella microsome assay with strains TA98 and TA100. The results of this study indicate that the mutagenicity of these diamines was the greatest for 4,4′‐diamino‐p‐terphenyl, followed by diaminophenylene and benzidine, with 4,4′‐diamino‐p‐quaterphenyl showing no mutagenicity.
Synthesis and mutagenic properties of direct dyes from 4,4′‐diamino‐p‐terphenyl and 4,4′‐diamino‐p‐quaterphenyl
Authors: Wang Jinlong , Freeman Harold S , Claxton Larry D
Published: January 2007

Disazo direct dyes were synthesised using bis‐diazotisation and coupling reactions involving 4,4′‐diamino‐p‐terphenyl and 4,4′‐diamino‐p‐quaterphenyl. The formation of the target dyes was confirmed by electrospray mass spectrometry and their mutagenicity was examined in the Salmonella microsome assay using TA98 and TA100. While most of these dyes were clearly non‐mutagenic, results from the Prival modification of the standard assay showed that Congo Red and its homologue derived from 4,4′‐diamino‐p‐terphenyl were clearly mutagenic.
Extraction and characterisation of non‐scourable chromophores from discoloured fleece wool
Authors: Dyer J M , Bringans S D , Aitken G D , Joyce N I , Bryson W G
Published: January 2007

The colour of scoured wool is a critical determinant of its value and quality, with the presence of significant non‐scourable discoloration severely limiting its use. In order to develop effective protocols for the removal or prevention of non‐scourable fleece wool discoloration, it is imperative that all significant contributing chromophores are characterised and their origin established. We describe the location, extraction and characterisation of chromophores from non‐scourable yellow fleece wool. Yellow discoloration was found to be located predominantly in the cuticular region of the wool fibre. Chromophoric compounds were extracted, isolated and characterised by tandem mass spectrometry, with five phenazine derivatives identified: phenazine, 1‐hydroxyphenazine, phenazine‐1‐carboxylic acid, pyocyanine and 1‐methoxyphenazine. Phenazines are brightly coloured pigments that are characteristic secondary metabolites of the bacterial genus Pseudomonas, a known ubiquitous component of the wool fleece microflora. The results of this research represent significant progress in our knowledge of wool discoloration, providing insight into both the chemical and microbial origin of non‐scourable wool yellowing.
Dyeing and antimicrobial studies on polyamine/epichlorohydrin condensate incorporated viscose rayon fibres
Authors: Bairagi N , Gulrajani M L , Deopura B L
Published: January 2007

Modified viscose rayon fibres were produced by incorporating different doses of polyamine/epichlorohydrin condensate in the dope. The modified fibres show excellent dyeability with heterobifunctional reactive dyes without electrolyte. The wash fastness and the light fastness of the modified fibres dyed with reactive dyes were good. The modified fibres also showed excellent dyeability on dyeing with different acid and metal‐complex dyes. The amount of additive present in the fibre was assessed from its nitrogen content and percentage exhaustion was found to increase with increasing quantity of additive. Tonal changes and increase in light fastness with acid and metal‐complex dyes have been attributed to the aggregation of dye in the fibre. Fibres containing more than 3% additive in the dope showed greater than 99% bacteria reduction on testing the antimicrobial activity against Escherichia coli and Staphylococcus aureus. It was observed that the antimicrobial activity deactivated on repeated washing using surfactants. The acid‐dyed fibres also showed a decrease in antimicrobial activity.
GC‐MS and 13C NMR Investigation of Lead Zirconate Titanate Precursor Sols for Fiber Preparation
Authors: Zhang Mei , Miranda Salvado Isabel M. , Vilarinho Paula M. , Silvestre Armando J. D. , Silva Artur M. S.
Published: January 2007

Different macroscopic properties of PZT fibers have been obtained when using acetic acid and methacrylic acid to modify the PZT precursor. In order to clarify the role of the acids the molecular structure of the acidified PZT precursors was investigated and compared by gas chromatography‐mass spectrometry, Fourier transform infrared, 13C nuclear magnetic resonance (NMR) spectroscopy (solution and solid state 13C NMR) and the reason for obtaining long PZT fibers is discussed. The results indicate that when methacrylic acid was used, long gel and ceramic fibers have been obtained because strongly co‐ordinating carboxylate groups of methacrylic acid were formed. Linear chains, like those of methacrylic acid propyl ester and methacrylic acetate, have been formed in the PZT precursor sols. In addition, after heat treatment the polymer decomposed quickly so that pure perovskite could be obtained at low temperature in the PZT fibers. When acetic acid was used short fibers were obtained. Acetic acid may act as chelate agent to form oxo acetate in the precursors; this oxo acetate nature also resulted in PZT fibers drawing. However, the longest gel and ceramic fibers have been prepared from precursors with methacrylic acid.
Is Glass Infiltration Beneficial to Improve Fretting Wear Properties for Alumina?
Authors: Sarkar Debasish , Basu Bikramjit , Chu Min Cheol , Cho Seong Jai
Published: January 2007

In this article, we report the tribological properties of the glass‐infiltrated (GI) alumina with a major aim to understand scientifically the influence of glass infiltration on the underlying mechanisms of material removal (when fretted against steel). For this purpose, the test samples were fabricated by infiltrating molten borosilicate glass on a sintered alumina. Thermal expansion coefficient mismatch of two phases (3.5 × 10−6°C−1 for glass and 9 × 10−6°C−1 for alumina) causes residual compressive stresses, which assists in the enhancement of mechanical properties. Systematic fretting wear experiments were performed on as‐sintered Al2O3 and GI alumina surface against bearing steel under dry‐unlubricated conditions at varying load (2 N, 5 N, and 10 N) with different fretting durations (10 000, 50 000, and 100 000 cycles). Relatively less variation in steady state COF (0.5–0.6) was measured for both the as‐sintered Al2O3 and GI Al2O3 under the varying operating conditions. Laser surface profilometer analysis indicates that better wear resistance could be obtained for GI alumina at lower load (2 N) after 100 000 fretting cycles (7.5 × 10−6 mm3/N·m), in comparison with the bare or virgin alumina surface (1.1 × 10−5 mm3/N·m). Also, the wear rate decreases with an increase in load to 5 N and 10 N, with the lowest value of 1.5 × 10−6 mm3/N ·m measured after fretting at 10 N load. Importantly, no noticeable difference in wear rate between as‐sintered and GI alumina could be measured at a higher load (5 N, 10 N). Atomic force microscopy and X‐ray diffraction analysis of wear debris illustrate that an amorphous tribolayer and finer debris particles, with composition of Fe(OH)3 and/or Fe2SiO4, adhere to the worn surface. The formation of triboreaction products has been explained using thermodynamically feasible reactions. The major wear mechanisms depend on the applied load and are being identified as fatigue wear, three‐body abrasion, and formation of a tribochemical layer.
Monophasic Nanostructured Powders of Niobium, Tantalum, and Hafnium Carbonitrides Synthesized by a Mechanically Induced Self‐Propagating Reaction
Authors: Córdoba José M. , Sayagués María J. , Alcalá María D. , Gotor F. J.
Published: January 2007

Niobium, tantalum, and hafnium carbonitride nanopowders were obtained by high‐energy ball milling of elemental metal and graphite in a nitrogen atmosphere. By adjusting milling parameters, a mechanically induced self‐propagating reaction was observed during the formation of carbonitride phases. The stoichiometry of transition metal carbonitrides was controlled by fixing the starting metal‐to‐carbon molar ratio. Ignition of the reactant mixture was determined by the combined effect of nitrogen and carbon, gas, and solid reagents, respectively. The composition and lattice parameters were determined by X‐ray diffraction measurements. Microstructural characterization showed a nanophase structure with a homogeneous chemical composition.
Polymer‐Assisted Annealing of Spray‐Pyrolyzed Powders for Formation of Luminescent Particles with Submicrometer and Nanometer Sizes
Authors: Wang Wei‐Ning , Kim Soon‐Gil , Wuled Lenggoro I. , Okuyama Kikuo
Published: January 2007

Phosphor nanoparticles (e.g., SrTiO3:Pr,Al and (Y,Gd)3Al5O12:Ce) were prepared using a conventional spray pyrolysis method in conjunction with a polymer‐assisted heat treatment (annealing). The effects of spray/annealing temperatures, polymer type, polymer concentration, and salt addition on the morphology, crystallinity, particle/crystal size, and the photoluminescence intensity of as‐prepared as well as annealed phosphor particles were investigated. The results showed that the nanocrystal growth of as‐prepared‐sprayed submicrometer particles was improved and that the nanocrystal networks disintegrate into nanoparticles when polymer or salt solutions are added during the heat‐treatment process. The additional combustion heat and gas evolution during the thermal reaction of polymer appear to be the main reasons for this. On the contrary, only compacted agglomerated particles rather than dispersed nanoparticles were found in the case of annealing without polymer/salt addition.
High‐Temperature Hydrogen Adsorption Properties of Precursor‐Derived Nickel Nanoparticle‐Dispersed Amorphous Silica
Authors: Ikuhara Yumi H. , Mori Hiroshi , Saito Tomohiro , Iwamoto Yuji
Published: January 2007

Nickel (Ni) nanoparticle‐dispersed amorphous silica (Si–O) powders were synthesized from chemical solution precursors. The high‐temperature hydrogen adsorption property of the precursor‐derived composite powders was investigated in comparison with the amorphous Si–O and Ni at 773 K. Among the three powder samples, Ni nanoparticle‐dispersed amorphous Si–O exhibited a unique reversible hydrogen adsorption property that was hardly detected on the amorphous Si–O and Ni. The increase amount of the reversibly adsorbed hydrogen was the highest for the composite samples at around the Ni content with a Ni/(Si+Ni) ratio of 0.2–0.3. The results strongly suggested that when the composite material is used in the form of a gas separation membrane, the reversibly adsorbed hydrogen property is thought to contribute to the additional increase in the number of solubility sites for hydrogen, which leads to a selective enhancement in the high‐temperature hydrogen permeance at 773 K.
Permeability of Green Ceramic Tapes as a Function of Binder Loading
Authors: Yun Jeong Woo , Lombardo Stephen J.
Published: January 2007

The permeability of green ceramic tapes was determined as a function of binder content for binder removed by air oxidation. The tapes were comprised of barium titanate as the dielectric, and polyvinyl butyral and dioctyl phthalate were the main components of the binder mixture. The flow in porous media through the tapes was analyzed in terms of models for describing Knudsen, slip, and Poiseuille flow mechanisms. The characteristic pore size was determined to be 1–2 μm, and thus Poiseuille flow was the dominant transport mechanism contributing to the flux. The permeability was then determined from Darcy's law for flow in porous media. The permeability was also determined from microstructural attributes in terms of the specific surface, the pore fraction, and a term to account for tortuosity and constrictions.
Self‐Reinforced Nitrogen‐Rich Calcium–α‐SiAlON Ceramics
Authors: Cai Yanbing , Shen Zhijian , Grins Jekabs , Esmaeilzadeh Saeid , Höche Thomas
Published: January 2007

Nitrogen‐rich Ca–α‐SiAlON ceramics with nominal compositions CaxSi12−2xAl2xN16 and 0.2≤x≤2.6, extending along the Si3N4–1/2Ca3N2:3AlN tie line, were prepared from Si3N4, AlN, and CaH2 precursors by hot pressing at 1800°C. The x values attained were determined by energy‐dispersive X‐ray (EDX) microanalysis and X‐ray powder diffraction (XRPD) data using the Rietveld method. The results show that Ca–α‐SiAlONs form continuously within the compositional range x=0 to at least x=1.82. Phase assemblages, lattice parameters, Vickers hardness, and fracture toughness were determined and correlated to the calcium content, x. Owing to a high sintering temperature and the use of CaH2 as a precursor, grain growth was kinetically enhanced, resulting in self‐reinforced microstructures with elongated grains. The obtained Ca–α‐SiAlON ceramics demonstrate a combination of both high hardness ∼21 GPa, and high fracture toughness ∼5.5 MPa·m1/2.
An audit to assess the outcome of a 1‐day acupuncture course for dentists
Authors: Rosted P. , Carrotte P.
Published: January 2007

Objective: The principal author has, during the last 4 years, given 45 1‐day courses in acupuncture involving 450 dentists arranged under the umbrella of continuous post‐graduate dental education. There is a paucity of evidence in the published dental literature regarding the outcomes after such courses, and the objective of this work was to analyse the outcome after a 1‐day acupuncture course.

Materials and methods: In co‐operation with the individual post‐graduate centres, a questionnaire was posted to all participants to ascertain whether; (a) the dentist has taken up acupuncture; (b) how often acupuncture was used; (c) any reasons for not incorporating acupuncture into the daily practice. To further evaluate the quality of the course, the following questions were addressed; (d) overall rating of the course; (e) the relevance of the course, assessed on a scale from 1 to 6 (1, highly unfavourable; 6, very high favourable).

Main outcome: A total of 209 (51.6%) questionnaires were returned, although 15 (3.7%) were subsequently excluded. The male:female ratio of respondents was 3:2, with an average age of 42 and 19 years of experience in dental practice. As many as 46% of respondents had incorporated acupuncture into their practice and 19% reported using acupuncture several times a month. The conditions treated were control of the gag reflex, stress management, sinusitis, headache and facial pain. The main reasons for not taking up acupuncture was ‘the dentist never actually got round to starting’ (83%) and lack of appropriate patients (60%).

Regarding the evaluation of the course, the assessment forms were obtained from 47% of the participants. Participants from all centres rated the course in the top end, 5.3 of 6.0 possible.
Validity and reliability of patient satisfaction questionnaires in a dental school in Japan
Authors: Imanaka Masahiro , Nomura Yoshiaki , Tamaki Yoh , Akimoto Naotake , Ishikawa Chieko , Takase Hideyo , Ishii Hiroaki , Yamachika Shigeo , Noda Koji , Ide Masamichi , Yamamoto Ken , Kokubo Yuji , Seto Kanichi
Published: January 2007

Purpose:  The purpose of this study was to construct questionnaires for the dental school setting from freely given patient answers with the aid of text mining, and to confirm the structure, reliability and validity of the questionnaires.

Methods:  Using these questionnaires, we carried out a survey of the satisfaction of patients treated at the Dental Hospital of the Tsurumi University School of Dental Medicine. A total of 3394 patients participated in the study. To confirm the reliability of inter‐item correlations and construct validity, factor analysis was carried out, and items belonging to each factor and Cronbach's alpha coefficients were calculated.

Results:  Four factors were extracted and 64.0% of the variance was explained by these four factors. All correlation coefficients were >0.85. These four factors were: ‘Treatment’, ‘Communication’, ‘Facilities’ and ‘Appearances’. From structural equation modelling, we determined that overall satisfaction was >0.75 and was statistically significant.

Conclusion:  The questionnaires used in this study are useful for measuring patient satisfaction in the dental school hospital setting.
What Happened to Pluto?
Authors: Consolmagno Guy
Published: January 2007

I had just finished speaking at the Cranbrook Museum of Science outside Detroit, presenting an hour-long talk about the newly defined dwarf planets, which covered the history of the IAU, the discovery of transneptunian objects (TNOs), the essentials of planetary nomenclature, and was full of PowerPoint graphics and erudite astronomy. The questions from the audience ranged from evolving planetary orbits to issues of surface geology. And then an eight-year-old boy, obviously surprised he'd been called on, turned slightly pink and burst out: “B-b-but… what happened to Pluto?”
Using Spreadsheets to Assess Learning
Authors: Wagner Judson E.
Published: January 2007

Spreadsheets can be a powerful tool when it comes to teaching physics. From data analysis and graphing to animated simulations, Excel® is a very versatile program for the educator and learner alike.1–4 This paper describes and supports another use for Excel through Reflective Formative Assessment Spreadsheets (RFAS). To illustrate the use of RFAS, Fig. 1 shows a released AP Physics5 question that one student, a group of students, or the entire class may see when they access a prepared RFAS file from a shared drive. Notice that this file has been given a PowerPoint® look by removing scrollbars and gridlines and by using the Full Screen option (Fig. 1, arrow a). Students navigate from one question to the next using the tabs (Fig. 1, arrow b).
In Vitro Inhibition of
Streptococcus mutans
Biofilm Formation on Hydroxyapatite by Subinhibitory Concentrations of Anthraquinones
Authors: Coenye Tom , Honraet Kris , Rigole Petra , Jimenez Pol Nadal , Nelis Hans J.
Published: January 2007

We report that certain anthraquinones (AQs) reduce
Streptococcus mutans
biofilm formation on hydroxyapatite at concentrations below the MIC. Although AQs are known to generate reactive oxygen species, the latter do not underlie the observed effect. Our results suggest that AQs inhibit
S. mutans
biofilm formation by causing membrane perturbation.
Resistance to Glycopeptide Antibiotics in the Teicoplanin Producer Is Mediated by
van
Gene Homologue Expression Directing the Synthesis of a Modified Cell Wall Peptidoglycan
Authors: Beltrametti Fabrizio , Consolandi Arianna , Carrano Lucia , Bagatin Francesca , Rossi Roberta , Leoni Livia , Zennaro Elisabetta , Selva Enrico , Marinelli Flavia
Published: January 2007

Glycopeptide resistance has been studied in detail in enterococci and staphylococci. In these microorganisms, high-level resistance is achieved by replacing the C-terminal
d
-alanyl-
d
-alanine of the nascent peptidoglycan with
d
-alanyl-
d
-lactate or
d
-alanyl-
d
-serine, thus reducing the affinities of glycopeptides for cell wall targets. Reorganization of the cell wall is directed by the expression of the
van
gene clusters. The identification of
van
gene homologs in the genomes of several glycopeptide-producing actinomycetes suggests the involvement of a similar self-resistance mechanism to avoid suicide. This report describes a comprehensive study of self-resistance in
Actinoplanes teichomyceticus
ATCC 31121, the producer of the clinically relevant glycopeptide teicoplanin.
A. teichomyceticus
ATCC 31121 showed a MIC of teicoplanin of 25 μg/ml and a MIC of vancomycin of 90 μg/ml during vegetative growth. The
vanH
,
vanA
, and
vanX
genes of
A. teichomyceticus
were found to be organized in an operon whose transcription was constitutive. Analysis of the UDP-linked peptidoglycan precursors revealed the presence of UDP-glycomuramyl pentadepsipeptide terminating in
d
-alanyl-
d
-lactate. No trace of precursors ending in
d
-alanyl-
d
-alanine was detected. Thus, the
van
gene complex was transcribed and expressed in the genetic background of
A. teichomyceticus
and conferred resistance to vancomycin and teicoplanin through the modification of cell wall biosynthesis. During teicoplanin production (maximum productivity, 70 to 80 μg/ml), the MIC of teicoplanin remained in the range of 25 to 35 μg/ml. Teicoplanin-producing cells were found to be tolerant to high concentrations of exogenously added glycopeptides, which were not bactericidal even at 5,000 μg/ml.
Population Structure and Resistance Genes in Antibiotic-Resistant Bacteria from a Remote Community with Minimal Antibiotic Exposure
Authors: Pallecchi Lucia , Lucchetti Chiara , Bartoloni Alessandro , Bartalesi Filippo , Mantella Antonia , Gamboa Herlan , Carattoli Alessandra , Paradisi Franco , Rossolini Gian Maria
Published: January 2007

In a previous study, we detected unexpectedly high levels of acquired antibiotic resistance in commensal
Escherichia coli
isolates from a remote Guaraní Indian (Bolivia) community with very low levels of antibiotic exposure and limited exchanges with the exterior. Here we analyzed the structure of the resistant
E. coli
population from that community and the resistance mechanisms. The
E. coli
population (113 isolates from 72 inhabitants) showed a high degree of genetic heterogeneity, as evidenced by phylogenetic grouping (77% group A, 10% group B1, 8% group D, 5% group B2) and genotyping by randomly amplified polymorphic DNA (RAPD) analysis (44 different RAPD types). The acquired resistance genes were always of the same types as those found in antibiotic-exposed settings [
bla
TEM
,
bla
PSE-1
,
catI
,
cmlA6
,
tet
(A),
tet
(B),
dfrA1
,
dfrA7
,
dfrA8
,
dfrA17
,
sul1
,
sul2
,
aphA1
,
aadA1
,
aadA2
,
aadA5
,
aadB
, and
sat-1
]. Class 1 and class 2 integrons were found in 12% and 4% of the isolates, respectively, and harbored arrays of gene cassettes similar to those already described. The cotransferability of multiple-resistance traits was observed from selected isolates and was found to be associated with resistance conjugative plasmids of the F, P, and N types. Overall, these data suggest that the resistance observed in this remote community is likely the consequence of the dissemination of resistant bacteria and resistance genes from antibiotic-exposed settings (rather than of an independent in situ selection) which involved both the clonal expansion of resistant strains and the horizontal transfer/recombination of mobile genetic elements harboring resistance genes.
Increased Genome Instability in
Escherichia coli lon
Mutants: Relation to Emergence of Multiple-Antibiotic-Resistant (Mar) Mutants Caused by Insertion Sequence Elements and Large Tandem Genomic Amplifications
Authors: Nicoloff Hervé , Perreten Vincent , Levy Stuart B.
Published: January 2007

Thirteen spontaneous multiple-antibiotic-resistant (Mar) mutants of
Escherichia coli
AG100 were isolated on Luria-Bertani (LB) agar in the presence of tetracycline (4 μg/ml). The phenotype was linked to insertion sequence (IS) insertions in
marR
or
acrR
or unstable large tandem genomic amplifications which included
acrAB
and which were bordered by IS
3
or IS
5
sequences. Five different
lon
mutations, not related to the Mar phenotype, were also found in 12 of the 13 mutants. Under specific selective conditions, most drug-resistant mutants appearing late on the selective plates evolved from a subpopulation of AG100 with
lon
mutations. That the
lon
locus was involved in the evolution to low levels of multidrug resistance was supported by the following findings: (i) AG100 grown in LB broth had an important spontaneous subpopulation (about 3.7 × 10
−4
) of
lon
::IS
186
mutants, (ii) new
lon
mutants appeared during the selection on antibiotic-containing agar plates, (iii)
lon
mutants could slowly grow in the presence of low amounts (about 2× MIC of the wild type) of chloramphenicol or tetracycline, and (iv) a
lon
mutation conferred a mutator phenotype which increased IS transposition and genome rearrangements. The association between
lon
mutations and mutations causing the Mar phenotype was dependent on the medium (LB versus MacConkey medium) and the antibiotic used for the selection. A previously reported unstable amplifiable high-level resistance observed after the prolonged growth of Mar mutants in a low concentration of tetracycline or chloramphenicol can be explained by genomic amplification.
The Anti-Trypanosoma cruziActivity of Posaconazole in a Murine Model of Acute Chagas' Disease Is Less Dependent on Gamma Interferon than That of Benznidazole
Authors: Ferraz Marcela L. , Gazzinelli Ricardo T. , Alves Rosana O. , Urbina Julio A. , Romanha Alvaro J.
Published: January 2007

We have investigated the influences of gamma interferon (IFN-γ) and interleukin-12 (IL-12) on the efficacy of posaconazole (POS) treatment of acute experimental infections withTrypanosoma cruzi; the standard drug, benznidazole (BZ), was used as a positive control. Wild-type (WT) mice infected withT. cruziand treated with POS or BZ had no parasitemia, 100% survival, and cure rates of 86 to 89%. IFN-γ-knockout (KO) mice infected withT. cruziand treated with BZ controlled the infection during treatment but relapsed after the drug pressure ceased and had 0% survival, while those receiving POS better controlled the infection after the end of treatment and had 70% survival (P< 0.0001 compared to the results for both untreated and BZ-treated animals). IL-12-KO mice infected and treated with POS or BZ had intermediate results, displaying enhanced parasitemia, decreased survival (77 to 83%), and reduced cure rates (35 to 39%) compared with those of the WT animals. Our results demonstrate that either IFN-γ or IL-12 deficiency reduces the efficacy of POS or BZ in this experimental model but also indicate that the anti-T. cruziactivity of POS is much less dependent on the activity of IFN-γ than that of BZ is.
Daptomycin Susceptibility of Unusual Gram-Positive Bacteria: Comparison of Results Obtained by the Etest and the Broth Microdilution Method
Authors: Huang Yu-Tsung , Liao Chun-Hsing , Teng Lee-Jeng , Hsueh Po-Ren
Published: January 2007

MICs of daptomycin, linezolid, and vancomycin against 212 isolates, including
Listeria monocytogenes
and
Pediococcus
,
Leuconostoc
,
Rhodococcus
, and
Nocardia
spp., were determined by the broth microdilution method; daptomycin MICs were also determined by the Etest. Except with those for
Leuconostoc
spp., daptomycin Etest MICs showed >90% agreement with MICs obtained by the broth microdilution method.
Universal In Vitro Antifungal Resistance of Genetic Clades of the
Fusarium solani
Species Complex
Authors: Azor Mónica , Gené Josepa , Cano Josep , Guarro Josep
Published: January 2007

Eleven antifungal drugs were tested against representative isolates of the four phylogenetic clades of the
Fusarium solani
species complex obtained in a multilocus sequence analysis. They all showed very poor activity, with no differences among the clades. Amphotericin B was the most active drug.
Survey of Genomic Diversity among
Enterococcus faecalis
Strains by Microarray-Based Comparative Genomic Hybridization
Authors: Aakra Ågot , Nyquist O. Ludvig , Snipen Lars , Reiersen Turid S. , Nes Ingolf F.
Published: January 2007

We have compared nine
Enterococcus faecalis
strains with
E. faecalis
V583 by comparative genomic hybridization using microarrays (CGH). The strains used in this study (the “test” strains) originated from various environments. CGH is a powerful and promising tool for obtaining novel information on genome diversity in bacteria. By CGH, one obtains clues about which genes are present or divergent in the strains, compared to a reference strain (here, V583). The information obtained by CGH is important from both ecological and systematic points of view. CGH of
E. faecalis
showed considerable diversity in gene content: Compared to V583, the percentage of divergent genes in the test strains varied from 15% to 23%, and 154 genes were divergent in all strains. The main variation was found in regions corresponding to exogenously acquired or mobile DNA in V583. Antibiotic resistance genes, virulence factors, and integrated plasmid genes dominated among the divergent genes. The strains examined showed various contents of genes corresponding to the pTEF1, pTEF2, and pTEF3 genes in V583. The extensive transport and metabolic capabilities of V583 appeared similar in the test strains; CGH indicated that the ability to transport and metabolize various carbohydrates was similar in the test strains (verified by API 50 CH assays). The contents of genes related to stress tolerance appeared similar in V583 and the nine test strains, supporting the view of
E. faecalis
as an organism able to resist harsh conditions.
Detection of
Vibrio cholerae
by Real-Time Nucleic Acid Sequence-Based Amplification
Authors: Fykse Else M. , Skogan Gunnar , Davies William , Olsen Jaran Strand , Blatny Janet M.
Published: January 2007

A multitarget molecular beacon-based real-time nucleic acid sequence-based amplification (NASBA) assay for the specific detection of
Vibrio cholerae
has been developed. The genes encoding the cholera toxin (
ctxA
), the toxin-coregulated pilus (
tcpA
; colonization factor), the
ctxA
toxin regulator (
toxR
), hemolysin (
hlyA
), and the 60-kDa chaperonin product (
groEL
) were selected as target sequences for detection. The beacons for the five different genetic targets were evaluated by serial dilution of RNA from
V. cholerae
cells. RNase treatment of the nucleic acids eliminated all NASBA, whereas DNase treatment had no effect, showing that RNA and not DNA was amplified. The specificity of the assay was investigated by testing several isolates of
V. cholerae
, other
Vibrio
species, and
Bacillus cereus
,
Salmonella enterica
, and
Escherichia coli
strains. The
toxR
,
groEL
, and
hlyA
beacons identified all
V. cholerae
isolates, whereas the
ctxA
and
tcpA
beacons identified the O1 toxigenic clinical isolates. The NASBA assay detected
V. cholerae
at 50 CFU/ml by using the general marker
groEL
and
tcpA
that specifically indicates toxigenic strains. A correlation between cell viability and NASBA was demonstrated for the
ctxA
,
toxR
, and
hlyA
targets. RNA isolated from different environmental water samples spiked with
V. cholerae
was specifically detected by NASBA. These results indicate that NASBA can be used in the rapid detection of
V. cholerae
from various environmental water samples. This method has a strong potential for detecting toxigenic strains by using the
tcpA
and
ctxA
markers. The entire assay including RNA extraction and NASBA was completed within 3 h.
Characterization of the Prokaryotic Diversity in Cold Saline Perennial Springs of the Canadian High Arctic
Authors: Perreault Nancy N. , Andersen Dale T. , Pollard Wayne H. , Greer Charles W. , Whyte Lyle G.
Published: January 2007

The springs at Gypsum Hill and Colour Peak on Axel Heiberg Island in the
Canadian Arctic originate from deep salt aquifers and are among the few
known examples of cold springs in thick permafrost on Earth. The
springs discharge cold anoxic brines (7.5 to 15.8% salts), with a mean
oxidoreduction potential of −325 mV, and contain high
concentrations of sulfate and sulfide. We surveyed the microbial
diversity in the sediments of seven springs by denaturing gradient gel
electrophoresis (DGGE) and analyzing clone libraries of 16S rRNA genes
amplified with
Bacteria
and
Archaea
-specific primers.
Dendrogram analysis of the DGGE banding patterns divided the springs
into two clusters based on their geographic origin. Bacterial 16S rRNA
clone sequences from the Gypsum Hill library (spring GH-4) were
classified into seven phyla (
Actinobacteria
,
Bacteroidetes
,
Firmicutes
,
Gemmatimonadetes
,
Proteobacteria
,
Spirochaetes
, and
Verrucomicrobia
);
Deltaproteobacteria
and
Gammaproteobacteria
sequences represented half of the clone
library. Sequences related to
Proteobacteria
(82%),
Firmicutes
(9%), and
Bacteroidetes
(6%) constituted
97% of the bacterial clone library from Colour Peak (spring CP-1). Most
GH-4 archaeal clone sequences (79%) were related to the
Crenarchaeota
while half of the CP-1 sequences were related to
orders
Halobacteriales
and
Methanosarcinales
of the
Euryarchaeota
. Sequences related to the sulfur-oxidizing
bacterium
Thiomicrospira psychrophila
dominated both the GH-4
(19%) and CP-1 (45%) bacterial libraries, and 56 to 76% of the
bacterial sequences were from potential sulfur-metabolizing bacteria.
These results suggest that the utilization and cycling of sulfur
compounds may play a major role in the energy production and
maintenance of microbial communities in these unique, cold
environments.
Impact of the Direct Application of Therapeutic Agents to the Terminal Recta of Experimentally Colonized Calves on
Escherichia coli
O157:H7 Shedding
Authors: Naylor Stuart W. , Nart Pablo , Sales Jill , Flockhart Allen , Gally David L. , Low J. Christopher
Published: January 2007

Enterohemorrhagic
Escherichia coli
O157:H7 is an important intestinal pathogen of humans with a main reservoir of domesticated ruminants, particularly cattle. It is anticipated that the risk of human infection can be reduced by controlling the organism within its reservoir hosts. Several options for the control of
E. coli
O157:H7 in cattle have been proposed, but none have been demonstrated to be successful in the field. Here we describe a novel experimental method, based on the terminal-rectum-restricted colonization described previously, to eliminate fecal carriage of
E. coli
O157:H7. In experimentally challenged calves, direct application to the rectal mucosa of either of two therapeutic agents, polymyxin B or chlorhexidine, greatly reduced bacterial shedding levels in the immediate posttreatment period. The most efficacious therapeutic agent, chlorhexidine, was compared in orally and rectally challenged calves. The treatment eliminated high-level shedding and reduced low-level shedding by killing bacteria at the terminal rectum. A rapid-detection system based on the ability to identify
E. coli
O157:H7 from swabs of the rectal mucosa was also assessed. This test was sufficiently sensitive to identify high-level bacterial carriage. Thus, a combination of the detection method and treatment regimens could be used in the field to eliminate high-level fecal excretion of
E. coli
O157:H7, so greatly reducing its prevalence within this host and the risk of human infection.
Quantitative and Qualitative β Diversity Measures Lead to Different Insights into Factors That Structure Microbial Communities
Authors: Lozupone Catherine A. , Hamady Micah , Kelley Scott T. , Knight Rob
Published: January 2007

The assessment of microbial diversity and distribution is a major concern in environmental microbiology. There are two general approaches for measuring community diversity: quantitative measures, which use the abundance of each taxon, and qualitative measures, which use only the presence/absence of data. Quantitative measures are ideally suited to revealing community differences that are due to changes in relative taxon abundance (e.g., when a particular set of taxa flourish because a limiting nutrient source becomes abundant). Qualitative measures are most informative when communities differ primarily by what can live in them (e.g., at high temperatures), in part because abundance information can obscure significant patterns of variation in which taxa are present. We illustrate these principles using two 16S rRNA-based surveys of microbial populations and two phylogenetic measures of community β diversity: unweighted UniFrac, a qualitative measure, and weighted UniFrac, a new quantitative measure, which we have added to the UniFrac website (
http://bmf.colorado.edu/unifrac
). These studies considered the relative influences of mineral chemistry, temperature, and geography on microbial community composition in acidic thermal springs in Yellowstone National Park and the influences of obesity and kinship on microbial community composition in the mouse gut. We show that applying qualitative and quantitative measures to the same data set can lead to dramatically different conclusions about the main factors that structure microbial diversity and can provide insight into the nature of community differences. We also demonstrate that both weighted and unweighted UniFrac measurements are robust to the methods used to build the underlying phylogeny.