bluuebunny/crossref_metadata_2025_split huggingface dataset:
A normative sample of isotonic and isokinetic muscle strength measurements in children 7 to 12 years of age
Authors: Holm I , Fredriksen PM , Fosdahl M , Vøllestad N 
Published: March 2008

AbstractAim: To provide normative age‐ and gender‐associated values on muscular strength, power and endurance and to establish a reference database on healthy school children aged 7 to 12 years. In addition, associations between some simple functional tests and the more sophisticated isokinetic strength measures were investigated.Methods: Three hundred seventy‐six children, 191 girls and 185 boys, performed different muscle‐strength tests like knee flexion/extension, handgrip, back extension and vertical jump.Results: There was a significant and linear increase in strength with no gender differences from 7 up to 11 years of age. There was a large variability within each age group, indicating that a normative sample of muscle‐strength measurements includes a wide range of values for each age group. The relationship between hand‐ grip strength and observed quadriceps strength was high (r = 0.84) and the correlation between vertical jump and relative quadriceps strength was moderate (r = 0.50).Conclusion: All the different strength measures showed almost the same pattern, indicating increased absolute strength values with increasing age and no significant gender differences except for flexion at the age of 11 and 12 years . The association between grip strength, vertical jump and quadriceps strength measured isokinetically was moderate to strong. The back muscle endurance test (The Biering–Sørensen test) showed a great roof effect and should not be included in a test battery for school children.
The comparative tuberculin test in guinea pigs using PPD extracts prepared from mycobacteria killed with phenol
Authors: CHOI C. S. , FROST A. J. , FRANCIS J. 
Published: March 2008

Summary. Purified‐protein‐derivative (PPD) extracts were prepared from Mycobacterium tuberculosis (PPD‐S), M. bovis (PPD‐BS), M. avium (PPD‐A) and M. kansasii (PPD‐K), after killing the cultures with phenol. The reactions were assessed in guinea pigs sensitised to a range of mycobacteria, with a view to selecting a suitable pairing of the extracts to distinguish sensitivity due to M. tuberculosis or M. bovis from that due to other mycobacteria.Sensitisation induced by M. bovis was best distinguished from others using PPD‐S and PPD‐A; for sensitisation by atypical mycobacteria, PPD‐BS was better than PPD‐S, used with either PPD‐K or PPD‐A, PPD‐BS was more specific than PPD‐S.Using PPD‐BS, PPD‐A and PPD‐K in a comparative test, 3 groups were recognised: those sensitive to M. bovis or M. tuberculosis (greatest reaction was to PPD‐BS); those sensitive to M. avium, M. Intracellulare and M. scrofulaceum (greatest reaction was to PPD‐A); those sensitive to M. kansasii, M. marium, M. gordonae and M. fortuitum (greatest reaction was to PPD‐K).
BOOK REVIEWS
Authors: Canfield P. J. , Halnan C. , Beh K. J. , Sabine M. 
Published: March 2008

Laboratory Profiles of Small Animal Diseases: a Guide to Laboratory Diagnosis. Charles Sodikoff, ed Paul W. Pratt. Santa Barbara Veterinary Publications 1981. pp 215. The Future of Beef Production in the European Community, Vol. 5, in current topics in Veterinary Medicine and Animal Science Seminar EEC Program of Co‐ordination of Research on Beef Production and Land Use, Italy, 1978. Ed J. C. Bowman and P. Susmel. Introduction to Veterinary Immunology. I. R. Tizard, W. B. Saunders, 1979. pp 367 $27.50. Viral Diseases of Farm Livestock. W. I. B. Beveridge (Animal Health in Australia, Vol. 1). Australian Bureau of Animal Health, Australian Government Publishing Service, Canberra 1981 pp 197.
Politics of municipal property taxes: implications for decision‐making
Authors: Kennedy William , McAllister Mary Louise 
Published: March 2008

Abstract: Property taxes are one of the few, important mechanisms through which municipal governments can exercise a measure of autonomy and determine policies that shape their local communities. Property taxes account for almost half of a municipality's own‐source revenues. Ideally, decisions surrounding property‐tax assessments could be based on criteria related to such things as equity, efficiency and stability. A closer examination of property‐tax assessments between property classes in Northern British Columbian municipalities, however, suggests that the setting of tax rates appears to be an incremental, rather than systematic, process that builds on past experiences, current demands, and observation of the practices of nearby municipalities. These findings suggest that property‐tax policy development is a poorly understood process that can have significant implications for the economic health of local municipalities.Sommaire: Les taxes fanciers ne sont que l'un des quelques rares et impotents mécanismes au moyen desquels les Governments municipaux prevent exercer une certain autonomic et determiner les propitious qui faqonnent leurs communautés locales. Les taxes foncières représentent près de la moitié des recettes d'une munici‐palité. En principe, les décisions entourant les évaluations de taxes foncières pour‐raient reposer sur des critères se rapportant à des facteurs comme l'équité, l'efficience et la stabilité. Un examen plus attentif d'évaluations des taxes foncières de différentes catégories dans les municipalités du Nord de la Colombie‐Britannique laisse entendre que l'établissement des taux de taxes semble être un processus pro‐gressif plutôt que systématique, reposant sur les expériences passées, les demandes actuelles et l'observation des pratiques des municipalités environnantes. Ces résul‐tats donnent à penser que l'élaboration d'une politique en matière de taxes foncières est un processus mal compris qui pourrait avoir d'importantes répercussions sur la santééconomique des municipalités locales.
Limitations to developing virtual communities in the public sector: A local government case study
Authors: Stefanick Lorna , LeSage Edward 
Published: March 2008

Abstract: This article explores how new information and communication technologies affect public administration practice. It examines efforts by the University of Alberta to develop a web‐based “meeting place,” an on‐line community of practice in the local government sector that was to be a forum for practice‐building discourse and a resource for professional development courses. While the MuniMall project was not an unequivocal success, it does provide important lessons for others who are contemplating similar projects. There are important differences between “open” and “closed” virtual communities, as well as differences among professional groups with respect to their receptivity to engaging in discourse in an open forum. For virtual communities targeted towards a specific professional community, critical factors for ensuring success include the readiness of site architecture upon rollout, as well as the culture, capacity and readiness of the audience.Sommaire: Le présent article approfondit la maniére dont les nouvelles technologies de I'information et de la communication influent sur I'exercice de l'administration public. I1 examine les efforts déployés par 1'Université de l'Alberta pour mettre en place un « lieu de rencontre » sur Internet, réseau en ligne d'échanges de pratiques dans le secteur de l'administration municipale qui devait être un forum de discussions sur le renforcement des pratiques et une resource pour les cours de perfection‐nement professionnel. Alors que le project « MuniMall » n'a pas été un succès sans équivoque, il foumit des leçons importantes à ceux qui envisagent des projects simi‐laires. I1 existe de grandes différences entre les communautés virtuelles « ouvertes » et « fermées », ainsi que des différences parmi les groupes professionnels en ce qui conceme leur réceptivitéà s'engager dans un discours au sein d'un forum ouvert. Pour les communautés virtuelles visant une communauté professionnelle particulière, les facers critiques de succès comprennent l'état de preparation de l'architcc‐ture ciu site dès sa mise en place, ainsi que la culture, la capacité et l'état de préparation de l'audience.
Biological Activities of Novel Gyrase Inhibitors of the Aminocoumarin Class
Authors: Anderle Christine , Stieger Martin , Burrell Matthew , Reinelt Stefan , Maxwell Anthony , Page Malcolm , Heide Lutz 
Published: March 2008

ABSTRACTThirty-one aminocoumarin antibiotics derived from mutasynthesis experiments were investigated for their biological activities. Their inhibitory activities towardEscherichia coliDNA gyrase were determined in two different in vitro assays: an ATPase assay and a DNA supercoiling assay. The assays gave a similar rank order of the activities of the compounds tested, although the absolute 50% inhibitory concentrations (IC50s) obtained in each assay were different. To confirm that the compounds also acted as gyrase inhibitors in vivo, reporter gene assays were carried out withE. coliby usinggyrAandsulApromoter fusions with theluxCDABEoperon. A strong induction of both promoters was observed for those compounds that showed gyrase inhibitory activity in the biochemical assays. Compounds carrying analogs of the prenylated benzoyl moiety (ring A) of clorobiocin that were structurally very different showed high levels of activity both in the biochemical assay and in the reporter gene assay, indicating that the structure of this moiety can be varied considerably without a loss of affinity for bacterial gyrase. The experimentally determined IC50s were compared to the binding energies calculated in silico, which indicated that a shift of the pyrrole carboxylic acid moiety from the O-3″ to the O-2″ position of the deoxysugar moiety has a significant impact on the binding mode of the compounds. The aminocoumarin compounds were also investigated for their MICs against different bacterial pathogens. Several compounds showed high levels of activity against staphylococci, including a methicillin-resistantStaphylococcus aureusstrain. However, they showed only poor activities against gram-negative strains.
Detection of Methyltransferases Conferring High-Level Resistance to Aminoglycosides in Enterobacteriaceae from Europe, North America, and Latin America
Authors: Fritsche Thomas R. , Castanheira Mariana , Miller George H. , Jones Ronald N. , Armstrong Eliana S. 
Published: March 2008

ABSTRACT

The alteration of ribosomal targets by recently described 16S rRNA methyltransferases confers resistance to most aminoglycosides, including arbekacin.
Enterobacteriaceae
and nonfermentative bacilli acquired through global surveillance programs were screened for the presence of these enzymes on the basis of phenotypes that were resistant to nine tested aminoglycosides. Subsequent molecular studies determined that 20 of 21 (95.2%) methyltransferase-positive isolates consisted of novel species records or geographic occurrences (North America [
armA
and
rmtB
], Latin America [
rmtD
], and Europe [
armA
];
rmtA
,
rmtC
, and
npmA
were not detected). The global emergence of high-level aminoglycoside resistance has become a rapidly changing event requiring careful monitoring.
Efficacy of Gamma Interferon and Specific Antibody for Treatment of Microsporidiosis Caused byEncephalitozoon cuniculiin SCID Mice
Authors: Salát Jiří , Jelínek Jiří , Chmelař Jindřich , Kopecký Jan 
Published: March 2008

ABSTRACTMicrosporidia are eukaryotic, obligate, intracellular protists that are emerging pathogens in immunocompromised hosts, including AIDS patients and organ transplant recipients. The efficacy of gamma interferon (IFN-γ) for the treatment of microsporidiosis caused byEncephalitozoon cuniculiwas studied by means of adoptive transfer and IFN-γ administration in SCID mice. While the adoptive transfer of CD4+T cells from immunocompetent mice prolonged survival of SCID mice infected perorally withE. cuniculi, survival was not improved by adoptive transfer of CD4+T lymphocytes from IFN-γ-deficient mice. The protective effect of IFN-γ was confirmed in cytokine therapy experiments in which SCID mice receiving IFN-γ survived significantly longer than mice receiving mock injections. The administration of serum containing specific antibodies againstE. cuniculiwas found to prolong the survival of concurrently IFN-γ-treated SCID mice. The data presented in this study suggest that IFN-γ is potentially useful as a cytokine therapy for microsporidiosis, especially in CD4+T-cell-deficient patients.
Susceptibility Testing of Anidulafungin and Voriconazole Alone and in Combination against Conidia and Hyphae of
Aspergillus
spp. under Hypoxic Conditions
Authors: Perkhofer Susanne , Jost Daniel , Dierich Manfred P. , Lass-Flörl Cornelia 
Published: March 2008

ABSTRACT

MICs and fractional inhibitory concentrations were evaluated for anidulafungin and voriconazole alone and in combination against conidia and hyphae under hypoxic (1% oxygen-5% CO
2
-94% nitrogen) conditions against 31
Aspergillus
isolates. Anidulafungin exhibited excellent activity against conidia and hyphae of
Aspergillus
spp. The visual reading of the MIC for anidulafungin was optimal under hypoxic conditions.
Identification of TbpA Residues Required for Transferrin-Iron Utilization by
Neisseria gonorrhoeae
Authors: Noto Jennifer M. , Cornelissen Cynthia Nau 
Published: March 2008

ABSTRACT

Neisseria gonorrhoeae
requires iron for survival in the human host and therefore expresses high-affinity receptors for iron acquisition from host iron-binding proteins. The gonococcal transferrin-iron uptake system is composed of two transferrin binding proteins, TbpA and TbpB. TbpA is a TonB-dependent, outer membrane transporter critical for iron acquisition, while TbpB is a surface-exposed lipoprotein that increases the efficiency of iron uptake. The precise mechanism by which TbpA mediates iron acquisition has not been elucidated; however, the process is distinct from those of characterized siderophore transporters. Similar to these TonB-dependent transporters, TbpA is proposed to have two distinct domains, a β-barrel and a plug domain. We hypothesize that the TbpA plug coordinates iron and therefore potentially functions in multiple steps of transferrin-mediated iron acquisition. To test this hypothesis, we targeted a conserved motif within the TbpA plug domain and generated single, double, and triple alanine substitution mutants. Mutagenized TbpAs were expressed on the gonococcal cell surface and maintained wild-type transferrin binding affinity. Single alanine substitution mutants internalized iron at wild-type levels, while the double and triple mutants showed a significant decrease in iron uptake. Moreover, the triple alanine substitution mutant was unable to grow on transferrin as a sole iron source; however, expression of TbpB compensated for this defect. These data indicate that the conserved motif between residues 120 and 122 of the TbpA plug domain is critical for transferrin-iron utilization, suggesting that this region plays a role in iron acquisition that is shared by both TbpA and TbpB.
Glycogen and Maltose Utilization by
Escherichia coli
O157:H7 in the Mouse Intestine
Authors: Jones Shari A. , Jorgensen Mathias , Chowdhury Fatema Z. , Rodgers Rosalie , Hartline James , Leatham Mary P. , Struve Carsten , Krogfelt Karen A. , Cohen Paul S. , Conway Tyrrell 
Published: March 2008

ABSTRACT

Mutant screens and transcriptome studies led us to consider whether the metabolism of glucose polymers, i.e., maltose, maltodextrin, and glycogen, is important for
Escherichia coli
colonization of the intestine. By using the streptomycin-treated mouse model, we found that catabolism of the disaccharide maltose provides a competitive advantage in vivo to pathogenic
E. coli
O157:H7 and commensal
E. coli
K-12, whereas degradation of exogenous forms of the more complex glucose polymer, maltodextrin, does not. The endogenous glucose polymer, glycogen, appears to play an important role in colonization, since mutants that are unable to synthesize or degrade glycogen have significant colonization defects. In support of the hypothesis that
E. coli
relies on internal carbon stores to maintain colonization during periods of famine, we found that by providing a constant supply of a readily metabolized sugar, i.e., gluconate, in the animal's drinking water, the competitive disadvantage of
E. coli
glycogen metabolism mutants is rescued. The results suggest that glycogen storage may be widespread in enteric bacteria because it is necessary for maintaining rapid growth in the intestine, where there is intense competition for resources and occasional famine. An important implication of this study is that the sugars used by
E. coli
are present in limited quantities in the intestine, making endogenous carbon stores valuable. Thus, there may be merit to combating enteric infections by using probiotics or prebiotics to manipulate the intestinal microbiota in such a way as to limit the availability of sugars preferred by
E. coli
O157:H7 and perhaps other pathogens.
Yersinia pestis caf1Variants and the Limits of Plague Vaccine Protection
Authors: Quenee Lauriane E. , Cornelius Claire A. , Ciletti Nancy A. , Elli Derek , Schneewind Olaf 
Published: March 2008

ABSTRACTYersinia pestis, the highly virulent agent of plague, is a biological weapon. Strategies that prevent plague have been sought for centuries, and immunization with live, attenuated (nonpigmented) strains or subunit vaccines with F1 (Caf1) antigen is considered effective. We show here that immunization with live, attenuated strains generates plague-protective immunity and humoral immune responses against F1 pilus antigen and LcrV.Y. pestisvariants lackingcaf1(F1 pili) are not only fully virulent in animal models of bubonic and pneumonic plague but also break through immune responses generated with live, attenuated strains or F1 subunit vaccines. In contrast, immunization with purified LcrV, a protein at the tip of type III needles, generates protective immunity against the wild-type and the fully virulentcaf1mutant strain, in agreement with the notion that LcrV can elicit vaccine protection against both types of virulent plague strains.
Genetic Evidence for an Alternative Citrate-Dependent Biofilm Formation Pathway in
Staphylococcus aureus
That Is Dependent on Fibronectin Binding Proteins and the GraRS Two-Component Regulatory System
Authors: Shanks Robert M. Q. , Meehl Michael A. , Brothers Kimberly M. , Martinez Raquel M. , Donegan Niles P. , Graber Martha L. , Cheung Ambrose L. , O'Toole George A. 
Published: March 2008

ABSTRACT

We reported previously that low concentrations of sodium citrate strongly promote biofilm formation by
Staphylococcus aureus
laboratory strains and clinical isolates. Here, we show that citrate promotes biofilm formation via stimulating both cell-to-surface and cell-to-cell interactions. Citrate-stimulated biofilm formation is independent of the
ica
locus, and in fact, citrate represses polysaccharide adhesin production. We show that fibronectin binding proteins FnbA and FnbB and the global regulator SarA, which positively regulates
fnbA
and
fnbB
gene expression, are required for citrate's positive effects on biofilm formation, and citrate also stimulates
fnbA
and
fnbB
gene expression. Biofilm formation is also stimulated by several other tricarboxylic acid (TCA) cycle intermediates in an FnbA-dependent fashion. While aconitase contributes to biofilm formation in the absence of TCA cycle intermediates, it is not required for biofilm stimulation by these compounds. Furthermore, the GraRS two-component regulator and the GraRS-regulated efflux pump VraFG, identified for their roles in intermediate vancomycin resistance, are required for citrate-stimulated cell-to-cell interactions, but the GraRS regulatory system does not impact the expression of the
fnbA
and
fnbB
genes. Our data suggest that distinct genetic factors are required for the early steps in citrate-stimulated biofilm formation. Given the role of FnbA/FnbB and SarA in virulence in vivo and the lack of a role for
ica
-mediated biofilm formation in
S. aureus
catheter models of infection, we propose that the citrate-stimulated biofilm formation pathway may represent a clinically relevant pathway for the formation of these bacterial communities on medical implants.
Wall Teichoic Acid Deficiency inStaphylococcus aureusConfers Selective Resistance to Mammalian Group IIA Phospholipase A2and Human β-Defensin 3
Authors: Koprivnjak Tomaz , Weidenmaier Christopher , Peschel Andreas , Weiss Jerrold P. 
Published: March 2008

ABSTRACTWall teichoic acids (WTAs) and membrane lipoteichoic acids (LTAs) are the major polyanionic polymers in the envelope ofStaphylococcus aureus. WTAs inS. aureusplay an important role in bacteriophage attachment and bacterial adherence to certain host cells, suggesting that WTAs are exposed on the cell surface and could also provide necessary binding sites for cationic antimicrobial peptides and proteins (CAMPs). Highly cationic mammalian group IIA phospholipase A2(gIIA PLA2) killsS. aureusat nanomolar concentrations by an action(s) that depends on initial electrostatic interactions, cell wall penetration, membrane phospholipid (PL) degradation, and activation of autolysins. AtagOmutant ofS. aureusthat lacks WTA is up to 100-fold more resistant to PL degradation and killing by gIIA PLA2and CAMP human β-defensin 3 (HBD-3) but has the sensitivity of the wild type (wt) to other CAMPs, such as Magainin II amide, hNP1-3, LL-37, and lactoferrin. In contrast, there is little or no difference in either gIIA PLA2activity toward cell wall-depleted protoplasts of the wt andtagOstrains ofS. aureusor in binding of gIIA PLA2to wt andtagOstrains. Scanning and transmission electron microscopy reveal increased surface protrusions in theS. aureus tagOmutant that might account for reduced activity of bound gIIA PLA2and HBD-3 toward thetagOmutant. In summary, the absence of WTA inS. aureuscauses a selective increase in bacterial resistance to gIIA PLA2and HBD-3, the former apparently by reducing access and/or activity of bound antibacterial enzyme to the bacterial membrane.
Lipooligosaccharides Containing Phosphorylcholine Delay Pulmonary Clearance of NontypeableHaemophilus influenzae
Authors: Pang Bing , Winn Dana , Johnson Ryan , Hong Wenzhou , West-Barnette Shayla , Kock Nancy , Swords W. Edward 
Published: March 2008

ABSTRACTNontypeableHaemophilus influenzae(NTHi) causes pulmonary infections in patients with chronic obstructive pulmonary disease and other mucociliary clearance defects. Like many bacteria inhabiting mucosal surfaces, NTHi produces lipooligosaccharide (LOS) endotoxins that lack the O side chain. Persistent NTHi populations express a discrete subset of LOS glycoforms, including those containing phosphorylcholine (PCho). In this study, we compared two NTHi strains with isogenic mutants lacking PCho for clearance from mice following pulmonary infection. Consistent with data from other model systems, populations of the strains NTHi 2019 and NTHi 86-028NP recovered from mouse lung contained an increased proportion of PCho+variants compared to that in the inocula. PCho−mutants were more rapidly cleared. Serial passage of NTHi increased both PCho content and bacterial resistance to clearance, and no such increases were observed for PCho−mutants. Increased PCho content was also observed in NTHi populations within non-endotoxin-responsive C3H/HeJ and Toll-like receptor 4 null (TLR4−/−) mice, albeit at later times postinfection. Changes in bacterial subpopulations and clearance were unaffected in TLR2−/−mice compared to the subpopulations in and clearance from mice of the parental strain. The clearance of PCho−mutants occurred at earlier time points in both strain backgrounds and in all types of mice. Comparison of bacterial populations in lung tissue cryosections by immunofluorescent staining showed sparse bacteria within the air spaces of C57BL/6 mice and large bacterial aggregates within the lungs of MyD88−/−mice. These results indicate that PCho promotes bacterial resistance to pulmonary clearance early in infection in a manner that is at least partially independent of the TLR4 pathway.