bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling environmentally associated morphological and genetic variation in a rainforest bird, and its application to conservation prioritization
Authors: Thomassen Henri A. , Buermann Wolfgang , Milá Borja , Graham Catherine H. , Cameron Susan E. , Schneider Christopher J. , Pollinger John P. , Saatchi Sassan , Wayne Robert K. , Smith Thomas B. 
Published: July 2009

AbstractTo better understand how environment shapes phenotypic and genetic variation, we explore the relationship between environmental variables across Ecuador and genetic and morphological variation in the wedge‐billed woodcreeper (Glyphorynchus spirurus), a common Neotropical rainforest bird species. Generalized dissimilarity models show that variation in amplified fragment length polymorphism markers was strongly associated with environmental variables on both sides of the Andes, but could also partially be explained by geographic distance on the western side of the Andes. Tarsus, wing, tail, and bill lengths and bill depth were well explained by environmental variables on the western side of the Andes, whereas only tarsus length was well explained on the eastern side. Regions that comprise the highest rates of genetic and phenotypic change occur along steep elevation gradients in the Andes. Such environmental gradients are likely to be particularly important for maximizing adaptive diversity to minimize the impacts of climate change. Using a framework for conservation prioritization based on preserving ecological and evolutionary processes, we found little overlap between currently protected areas in Ecuador and regions we predicted to be important in maximizing adaptive variation.
Current challenges in understanding melanogenesis: bridging chemistry, biological control, morphology, and function
Authors: Simon John D , Peles Dana , Wakamatsu Kazumasa , Ito Shosuke 
Published: July 2009

SummaryMelanin is a natural pigment produced within organelles, melanosomes, located in melanocytes. Biological functions of melanosomes are often attributed to the unique chemical properties of the melanins they contain; however, the molecular structure of melanins, the mechanism by which the pigment is produced, and how the pigment is organized within the melanosome remains to be fully understood. In this review, we examine the current understanding of the initial chemical steps in the melanogenesis. Most natural melanins are mixtures of eumelanin and pheomelanin, and so after presenting the current understanding of the individual pigments, we focus on the mixed melanin systems, with a critical eye towards understanding how studies on individual melanin do and do not provide insight in the molecular aspects of their structures. We conclude the review with a discussion of important issues that must be addressed in future research efforts to more fully understand the relationship between molecular and functional properties of this important class of natural pigments.
The taming of the shrew? The immunology of corneal transplantation
Authors: Pleyer Uwe , Schlickeiser Stephan 
Published: July 2009

Abstract.Corneal transplantation, first reported a century ago, is the oldest and most frequent form of solid tissue transplantation. Although keratoplasty is also considered as the most successful transplant procedure, several studies indicate that the long term survival of corneal grafts is even lower than that of transplanted parenchymatous organs. Despite the immune privilege enjoyed by the cornea and anterior segment of the eye, immunologic graft rejection is a major limitation to corneal transplantation. This review gives an update on corneal immunobiology and the mechanisms of corneal graft rejection, focusing on antigen presentation, as well as on the molecular and cellular mediators of this particular immune response.
Obstacles to action in arthritis: a community case‐control study
Authors: HUTTON Ingrid , GAMBLE Greg , MCLEAN Grant , BUTCHER Hugh , GOW Peter , DALBETH Nicola 
Published: July 2009

AbstractObjective: Despite the benefits of physical activity, people with arthritis are less active than the general population. The aim of this study was to determine the motivators and obstacles to physical activity for adults with arthritis.Methods: Participants were identified from the Obstacles to Action Study, a community based study of 8163 adults, which explored barriers and motivators to physical activity. A 1 : 1 case‐control study was designed; cases were identified as those participants who reported arthritis (n = 1106). Each case was matched with an age, sex and ethnicity‐matched non‐arthritis control (n = 1106).Results: Cases were less likely to achieve recommended physical activity targets (58.8%vs. 68.1%P = 0.00001). Furthermore, fewer people with arthritis believed that physical activity would help them lead healthy lives (86.7%vs. 91.3%P = 0.006) or viewed physical activity as a priority (53.8%vs. 59.8%P = 0.005). Cases were less confident in their abilities to try a new activity (37.1%vs. 43.7%P = 0.002) or maintain a healthy weight (65.0%vs. 74.3%P = 0.00001). Cases also reported greater negative impact scores for barriers to activity, particularly arthritis, accessibility, cost and discomfort while exercising. Motivators and environmental barriers to activity were similar for cases and controls. These findings persisted after adjusting for educational level, body mass index and comorbidities.Conclusion: People with arthritis are less active and demonstrate different attitudes toward physical activity. Although people with arthritis identify similar environmental barriers, they have different psychosocial barriers. In order to design effective physical activity programs for people with arthritis, these barriers must be specifically addressed.
Bilateral atypical femoral diaphyseal fractures in a patient treated with alendronate sodium
Authors: LEE Joon Kiong 
Published: July 2009

AbstractAntiresorptive agents have been used as primary or first‐line therapy in managing patients with osteoporosis. Bisphosphonates in particular are used widely to reduce bone resorption, increase bone mineral density, improve bone quality and therefore reduce fracture risk. However, prolonged use of bisphosphonates may cause over‐suppression of bone resorption, leading on to accumulation of micro‐damage in bone. This in turn might lead on to atypical femoral fractures. A patient treated with alendronate sodium for 8 years, and presenting with bilateral atypical femoral diaphyseal fractures is reported. X‐rays of both femurs showed typical horizontal fracture line involving the thick lateral cortex with short oblique fracture pattern over the medial cortex. This fracture pattern was further confirmed with intra‐operative examination of the fracture ends. Histopathological examination of the endocortical fragment removed from the proximal fracture end showed absence of osteoclasts and osteoblasts. Bone mineral density with dual energy X‐ray absorptiometry (DXA) scan showed osteopenia over the femoral neck. Blood investigations did not show significant abnormalities. Bone turnover marker levels were not reliable, as presence of fracture might have altered the marker levels. Both femoral fractures united well. The patient reported here had complete pictures on X‐ray examination, intra‐operative findings, histopathological examination, DXA, as well as blood test results. Complete data should be collected from patients treated with alendronate sodium presenting with atypical femoral fractures to show any link between the use of alendronate sodium with atypical fracture of femur.
The Pho regulon influences biofilm formation and type three secretion in Pseudomonas aeruginosa
Authors: Haddad Ahmed , Jensen Vanessa , Becker Tanja , Häussler Susanne 
Published: July 2009

SummaryResearch into the molecular mechanisms of the switch from highly motile to biofilm forming Pseudomonas fluorescens bacteria recently uncovered a role of inorganic phosphate as an important environmental regulatory factor to control c‐di‐GMP levels in the cell. In this study we present evidence that in the opportunistic pathogen P. aeruginosa the Pho regulon inhibits biofilm formation and is required for the repression of the type three secretion system. We furthermore identified an EAL domain protein as a downstream effector of the Pho regulon, which at least partially mediated the observed inhibition. Interestingly, inhibition of the P. aeruginosa virulence phenotype was Pho regulon‐dependent in both a PA14 and a PAO1 strain background; however, in PA14 this inhibition was independent on the availability of inorganic phosphate, whereas in PAO1 phosphate enhanced biofilm formation independently of the inhibitory activity of the Pho regulon. These results clearly show that the Pho regulon contributes to the expression of the virulence phenotype in P. aeruginosa and add even more complexity to the strain‐specific regulation of bacterial behaviour by environmental cues.
Perfect powers from products of consecutive terms in arithmetic progression
Authors: Győry K. , Hajdu L. , Pintér Á. 
Published: July 2009

AbstractWe prove that for any positive integersx,dandkwith gcd (x,d)=1 and 3<k<35, the productx(x+d)⋯(x+(k−1)d) cannot be a perfect power. This yields a considerable extension of previous results of Győryet al.and Bennettet al., which covered the cases wherek≤11. We also establish more general theorems for the case wherexcan also be a negative integer and where the product yields an almost perfect power. As in the proofs of the earlier theorems, for fixedkwe reduce the problem to systems of ternary equations. However, our results do not follow as a mere computational sharpening of the approach utilized previously; instead, they require the introduction of fundamentally new ideas. Fork>11, a large number of new ternary equations arise, which we solve by combining the Frey curve and Galois representation approach with local and cyclotomic considerations. Furthermore, the number of systems of equations grows so rapidly withkthat, in contrast with the previous proofs, it is practically impossible to handle the various cases in the usual manner. The main novelty of this paper lies in the development of an algorithm for our proofs, which enables us to use a computer. We apply an efficient, iterated combination of our procedure for solving the new ternary equations that arise with several sieves based on the ternary equations already solved. In this way, we are able to exclude the solvability of the enormous number of systems of equations under consideration. Our general algorithm seems to work for larger values ofkas well, although there is, of course, a computational time constraint.
Addition of Gentamicin or Rifampin Does Not Enhance the Effectiveness of Daptomycin in Treatment of Experimental Endocarditis Due to Methicillin-Resistant
Staphylococcus aureus
Authors: Miró J. M. , García-de-la-Mària C. , Armero Y. , Soy D. , Moreno A. , del Río A. , Almela M. , Sarasa M. , Mestres C. A. , Gatell J. M. , Jiménez de Anta M. T. , Marco F. 
Published: July 2009

ABSTRACT

This study evaluated the activity of daptomycin combined with either gentamicin or rifampin against three methicillin-resistant
Staphylococcus aureus
(MRSA) clinical isolates in vitro and one isolate in vivo against a representative strain (MRSA-572). Time-kill experiments showed that daptomycin was bactericidal against these strains at concentrations over the MIC. Daptomycin at sub-MIC concentrations plus gentamicin at 1× and 2× the MIC yielded synergy, while the addition of rifampin at 2 to 4 μg/ml resulted in indifference (two strains) or antagonism (one strain). The in vivo activity of daptomycin (6 mg/kg of body weight once a day) was evaluated ± gentamicin (1 mg/kg intravenously [i.v.] every 8 h [q8h]) or rifampin (300 mg i.v. q8h) in a rabbit model of infective endocarditis by simulating human pharmacokinetics. Daptomycin plus gentamicin (median, 0 [interquartile range, 0 to 2] log
10
CFU/g vegetation) was as effective as daptomycin alone (0 [0 to 2] log
10
CFU/g vegetation) in reducing the density of bacteria in valve vegetations (
P
= 0.83), and both were more effective than daptomycin plus rifampin (3 [2 to 3.5] log
10
CFU/g vegetation;
P
< 0.05) for the strain studied. In addition, daptomycin sterilized a ratio of vegetations that was similar to that of daptomycin plus gentamicin (10/15 [67%] versus 9/15 [60%];
P
= 0.7), and both regimens did so more than daptomycin plus rifampin (3/15 [20%];
P
= 0.01 and
P
= 0.02, respectively). No statistical difference was noted between daptomycin plus gentamicin and daptomycin alone for MRSA treatment. In the combination arm, all isolates from vegetations remained susceptible to daptomycin, gentamicin, and rifampin. Sixty-one percent of the isolates (8/13) acquired resistance to rifampin during monotherapy. In the daptomycin arm, resistance was detected in only one case, in which the daptomycin MIC rose to 2 μg/ml among the recovered bacteria. In conclusion, the addition of gentamicin or rifampin does not enhance the effectiveness of daptomycin in the treatment of experimental endocarditis due to MRSA.
Evaluating Aztreonam and Ceftazidime Pharmacodynamics withEscherichia coliin Combination with Daptomycin, Linezolid, or Vancomycin in an In Vitro Pharmacodynamic Model
Authors: LaPlante Kerry L. , Sakoulas George 
Published: July 2009

ABSTRACTIn an in vitro pharmacodynamic model, linezolid attenuated the activity of aztreonam and ceftazidime againstEscherichia coli. Conversely, synergy was detected at 24 and 48 h when daptomycin or vancomycin was added to aztreonam and ceftazidime. We conclude that significant yet underappreciated interactions may occur between gram-positive-spectrum and gram-negative-spectrum antibacterials.
Development and Validation of a Fluorescent Microsphere Immunoassay for Soluble CD30 Testing
Authors: Pavlov Igor , Martins Thomas B. , Delgado Julio C. 
Published: July 2009

ABSTRACTTesting for soluble CD30 (sCD30), an indicator of Th2 immune response, is a useful prognostic marker in solid organ transplantation, lymphoproliferative disorders, autoimmunity, and various parasitic diseases. In this study we report the development and validation of a fluorescent microsphere immunoassay for the detection of sCD30 in serum, plasma, and culture supernatants. The dynamic range of this assay is 1 to 400 ng/ml, and the rate of recovery of various concentrations of recombinant sCD30 ranges from 97 to 116% (average recovery, 105%). The test showed a high degree of precision in both intra-assay and interassay studies (coefficients of variation, as high as 7% and 8%, respectively), with a sensitivity of 1 ng/ml. The normal reference range calculated for a cohort of 151 healthy individuals was 1 to 29 ng/ml. The clinical usefulness of the sCD30 fluorescent microsphere immunoassay was demonstrated by showing that levels of sCD30 have a positive correlation with specimens containing high titers of anti-double-stranded DNA antibodies and high titers of immunoglobulin G againstLeishmaniaspecies. Given the multiplexing potential of the sCD30 fluorescent microsphere immunoassay reported in this study, it is expected that testing of sCD30 concentrations along with those of other cytokines will become an important diagnostic tool for selected immunological and inflammatory diseases where Th2-type cytokine responses have been reported.
Antiretroviral Therapy Restores Diversity in the T-Cell Receptor Vβ Repertoire of CD4 T-Cell Subpopulations among Human Immunodeficiency Virus Type 1-Infected Children and Adolescents
Authors: Yin Li , Kou Zhong Chen , Rodriguez Carina , Hou Wei , Goodenow Maureen M. , Sleasman John W. 
Published: July 2009

ABSTRACTHuman immunodeficiency virus (HIV) type 1 infection perturbs the T-cell receptor (TCR) Vβ repertoire. The TCR CDR3 length diversity of individual Vβ families was examined within CD45RA and CD45RO CD4 T cells to assess the impact of the virus on clonality throughout CD4 T-cell activation and differentiation. A cross-sectional and longitudinal cohort study of 13 HIV-infected and 8 age-matched healthy children and adolescents examined the Vβ CDR3 length profiles within CD4 T-cell subsets by the use of spectratyping. HIV-infected subjects demonstrated higher numbers of perturbations in CD4 CD45RA T cells (5.8 ± 4.9 Vβ families) than healthy individuals (1.6 ± 1.8 Vβ families) (P= 0.04). Surprisingly, CD4 CD45RO central memory T cells from infected subjects showed no increased perturbations compared to the perturbations for the same cells from healthy subjects (2.9 ± 3.1 and 1.1 ± 1.8 Vβ families, respectively;P= 0.11). CD4 CD45RA TCR perturbations were higher among infected subjects with >25% CD4 cells than healthy subjects (mean number of perturbed Vβfamilies, 6.6 ± 5.4;P= 0.04). No correlations between perturbations in CD4 subsets and pretherapy age or viral load were evident. In contrast to CD8 T cells, HIV induces TCR disruptions within CD45RA but not CD45RO CD4 T cells. Therapy-induced viral suppression resulted in increases in thymic output and the normalization of the diversity of TCR within CD45RA CD4 T cells after 2 months of treatment. Perturbations occur prior to CD4 T-cell attrition and normalize with effective antiretroviral therapy. The impact of HIV on the diversity of TCR within naïve, central memory, and effector memory CD4 T cells is distinctly different from that in CD8 T cells.
The Flagella of an Atypical Enteropathogenic
Escherichia coli
Strain Are Required for Efficient Interaction with and Stimulation of Interleukin-8 Production by Enterocytes In Vitro
Authors: Sampaio Suely C. F. , Gomes Tânia A. T. , Pichon Christophe , du Merle Laurence , Guadagnini Stéphanie , Abe Cecilia M. , Sampaio Jorge L. M. , Le Bouguénec Chantal 
Published: July 2009

ABSTRACT

The ability of some typical enteropathogenic
Escherichia coli
(EPEC) strains to adhere to, invade, and increase interleukin-8 (IL-8) production in intestinal epithelial cells in vitro has been demonstrated. However, few studies regarding these aspects have been performed with atypical EPEC (aEPEC) strains, which are emerging enteropathogens in Brazil. In this study, we evaluated a selected aEPEC strain (1711-4) of serotype O51:H40, the most prevalent aEPEC serotype in Brazil, in regard to its ability to adhere to and invade Caco-2 and T84 cells and to elicit IL-8 production in Caco-2 cells. The role of flagella in aEPEC 1711-4 adhesion, invasion, and IL-8 production was investigated by performing the same experiments with an isogenic aEPEC mutant unable to produce flagellin (FliC), the flagellum protein subunit. We demonstrated that this mutant (
fliC
mutant) had a marked decrease in the ability to adhere to T84 cells and invade both T84 and Caco-2 cells in gentamicin protection assays and by transmission electron microscopy. In addition, the aEPEC 1711-4
fliC
mutant had a reduced ability to stimulate IL-8 production by Caco-2 cells in early (3-h) but not in late (24-h) infections. Our findings demonstrate that flagella of aEPEC 1711-4 are required for efficient adhesion, invasion, and early but not late IL-8 production in intestinal epithelial cells in vitro.
Inhibitory Antibodies Specific for the 19-Kilodalton Fragment of Merozoite Surface Protein 1 Do Not Correlate with Delayed Appearance of Infection withPlasmodium falciparumin Semi-Immune Individuals in Vietnam
Authors: Murhandarwati E. Elsa Herdiana , Wang Lina , Black Casilda G. , Nhan Doan Hanh , Richie Thomas L. , Coppel Ross L. 
Published: July 2009

ABSTRACTInhibitory antibodies specific for the 19-kDa fragment of merozoite surface protein 1 (MSP119) are a significant component of inhibitory responses in individuals immune to malaria. Nevertheless, conflicting results have been obtained in determining whether this antibody specificity correlates with protection in residents of areas where malaria is endemic. In this study, we examined sera collected from a population of semi-immune individuals living in an area of Vietnam with meso-endemicity during a 6-month period. We used twoPlasmodium falciparumparasite lines that express either endogenous MSP119or the homologous region fromPlasmodium yoeliito measure the MSP119-specific inhibitory activity. We showed that (i) the level of MSP119-specific inhibitory antibodies was not associated with a delay inP. falciparuminfection, (ii) MSP119-specific inhibitory antibodies declined significantly during the convalescent period after infection, and (iii) there was no significant correlation between the MSP119-specific inhibitory antibodies and the total antibodies measured by enzyme-linked immunosorbent assay. These results have implications for understanding naturally acquired immunity to malaria and for the development and evaluation of MSP119-based vaccines.
Direct Sequencing of
Legionella pneumophila
from Respiratory Samples for Sequence-Based Typing Analysis
Authors: Coscollá Mireia , González-Candelas Fernando 
Published: July 2009

ABSTRACT

We have developed a procedure to test the efficiency and reliability of sequencing of
Legionella pneumophila
genes directly from respiratory samples and have compared the results with those derived from cultured isolates. We tried to obtain the nucleotide sequences of six protein-coding loci included in the sequence-based typing scheme for
Legionella pneumophila
and three intergenic regions from 132 samples corresponding to 106 patients positive for urine antigen. A seminested PCR approach was used to amplify and sequence these nine loci directly from respiratory samples. Nucleotide sequences were directly obtained for 23
Legionella
isolates and also for 66 respiratory secretions from a total of 69 patients. The efficiency of sequencing from respiratory secretions was higher than that of sequencing after the isolation of the
Legionella
isolates. Moreover, the perfect match between the sequences obtained by both approaches when respiratory samples and cultured isolates from the same patient were available corroborates the suitability of the direct sequencing approach for the identification of
Legionella
species and molecular epidemiology studies with
Legionella
species.
Cooccurrence of Predominant Panton-Valentine Leukocidin-Positive Sequence Type (ST) 152 and Multidrug-Resistant ST 241
Staphylococcus aureus
Clones in Nigerian Hospitals
Authors: Okon Kenneth O. , Basset Patrick , Uba Auwalu , Lin Johnson , Oyawoye Bukola , Shittu Adebayo O. , Blanc Dominique S. 
Published: July 2009

ABSTRACT

Ninety-six clinical isolates of
Staphylococcus aureus
from Nigeria were characterized phenotypically and genetically. Twelve multidrug-resistant methicillin (meticillin)-resistant
S. aureus
(MRSA) isolates carrying a new staphylococcal cassette chromosome
mec
element and a high proportion of Panton-Valentine leukocidin (PVL)-positive methicillin-susceptible
S. aureus
(MSSA) isolates were observed. The cooccurrence of multidrug-resistant MRSA and PVL-positive MSSA isolates entails the risk of emergence of a multidrug-resistant PVL-positive MRSA clone.