bluuebunny/crossref_metadata_2025_split huggingface dataset:
An immunological approach to quantifying the saprotrophic growth dynamics ofTrichodermaspecies during antagonistic interactions withRhizoctoniasolani in a soil‐less mix
Authors: Thornton Christopher R. 
Published: March 2004

SummaryStudies of the saprotrophic growth dynamics ofTrichodermaspecies and their fungal hosts during antagonistic interactions are severely hampered by the absence of methods that allow the unambiguous identification and quantification of individual genera in complex environments such as soil or compost containing mixed populations of fungi. Furthermore, methods are required that allow discrimination between active hyphal growth and other components of fungal biomass such as quiescent spores that are produced in large numbers byTrichodermaspecies. This study details the use of monoclonal antibodies to quantify the saprotrophic growth dynamics of the soil‐borne plant pathogenRhizoctonia solaniand biological control strains ofTrichoderma asperellumandTrichoderma harzianumduring antagonistic interactions in peat‐based microcosms. Quantification was based on the immunological detection of constitutive, extracellular antigens that are secreted from the growing tip ofRhizoctoniaandTrichodermamycelium and, in the case ofTrichoderma harzianum, from quiescent phialoconidia also. TheTrichoderma‐specific monoclonal antibody (MF2) binds to a protein epitope of the enzyme glucoamylase, which was shown by immunofluorescence and immunogold electron gold microscopy studies ofTrichoderma virens in vitroto be produced at the origin of germ tube emergence in phialoconidia and from the growing tip of germ tubes. In addition, a non‐destructive immunoblotting technique showed that the enzyme was secreted during active growth ofTrichoderma asperellummycelium in peat. TheRhizoctonia solani‐specific monoclonal antibody (EH2) similarly binds to a protein epitope of a glycoprotein that is secreted during active mycelial growth. Extracts derived from lyophilized mycelium were used as a quantifiable and repeatable source of antigens for construction of calibration curves. These curves were used to convert the absorbance values obtained in ELISA tests of peat extracts to biomass equivalents, which allowed comparisons of the saprotrophic growth dynamics of the pathogen and antagonists to be made in single or mixed species microcosms.Trichodermaspecies were able to compete successfully withR. solanifor nutrients and to prevent saprotrophic growth of the pathogen. Specificity of theTrichodermaquantitative assay was tested in non‐sterile soil‐based microcosms artificially inoculated withT. asperellum. The assay was highly specific and only detectedT. asperellumpopulation dynamics. No cross‐reactivity was found with extracts from soil samples containing contaminant fungi.
Polymerase chain reaction denaturing gradient gel electrophoresis analysis of the N2‐fixing bacterial diversity in soil under Acacia tortilis ssp. raddiana and Balanites aegyptiaca in the dryland part of Senegal
Authors: Demba Diallo Moudjahidou , Willems Anne , Vloemans Nele , Cousin Sylvie , Vandekerckhove Tom T. , De Lajudie Philippe , Neyra Marc , Vyverman Wim , Gillis Monique , Van der Gucht Katleen 
Published: March 2004

SummaryDenaturing gradient gel electrophoresis (DGGE) of amplified nifH gene fragments was used to study the diazotrophic community of soil samples under Acacia tortilis ssp. raddiana (legume tree) and Balanites aegyptiaca (non‐legume tree), two dominant plant species growing naturally in the dryland part of Senegal. Samples were taken along transects from the stem up to 10 m distance from it, at depths of 0–0.25 m and 0.25–0.50 m. Sampling was done in the dry season (25 June 1999) and in the rainy season (28 August 1999). The community structure and diversity of the bacterial groups from the different samples was analysed further using different techniques, such as statistical analysis and diversity index evaluation of the band patterns. Diazotrophic diversity was lower under B. aegyptiaca than under A. tortilis ssp. raddiana. Multidimensional scaling (MDS) analysis and ANOSIM tests showed a significant effect of the tree on the diazotroph assemblages. SIMPER analysis showed that the major elements responsible for the dissimilarity are a member of the genus Sinorhizobium, which is characteristic of the samples taken under A. tortilis ssp. raddiana and a member of the cluster Bradyrhizobium for the samples taken under B. aegyptiaca. Forty‐four major bands were partially sequenced, yielding 33 different nifH sequences, which were used in phylogenetic reconstructions. Most sequences were affiliated with the alpha‐ beta‐ and gamma‐proteobacteria. Five nifH sequences were identical to those of Pseudomonas stutzeri, and one sequence showed 100% similarity to that of Azotobacter vinelandii. Four bands were affiliated with the Cyanobacteria and a single one with the Firmicutes. For both trees, there were also clear differences between the samples taken in the dry and rainy seasons. Only for the samples taken under A. tortilis ssp. raddiana was a significant difference found between the two sampling depths.
N‐acyl‐l‐homoserine lactones (AHLs) affect microbial community composition and function in activated sludge
Authors: Valle Anna , Bailey Mark J. , Whiteley Andrew S. , Manefield Mike 
Published: March 2004

SummaryThe role of intercellular signalling in the regulation of genes and phenotypes in a broad range of bacterial species is now firmly established. In contrast, the impact of intercellular signalling on microbial community parameters, such as species diversity and function, is less well understood. In this study the role of N‐acyl‐l‐homoserine lactones (AHLs) in microbial community dynamics in an industrial wastewater treatment system is addressed. Seven proteobacterial strains producing compounds with AHL‐like activity were isolated from the treatment plant. Three of these belong to genera with no previously identified AHL producing species. Addition of AHLs at 2 µM to sludge samples generated changes in both community function (phenol degradation) and composition as determined by length heterogeneity PCR and denaturing gradient gel electrophoresis. Phenol degradation was more stable as a result of the AHL augmentation. A dominant functional member of the Thauera genus was transiently supplanted by a member of the Comomonas genus in response to AHL addition. This suggests that AHLs can play a role in mediating microbial community parameters and has implications for ecosystem function and industrial wastewater treatment.
An Analysis of the General Practice Access Scheme on GP Incomes, Bulk Billing and Consumer Copayments
Authors: Savage Elizabeth , Jones Glenn 
Published: March 2004

AbstractIn response to falling rates of bulk billing, in April 2003 the Australian Government proposed changes to the way that general practitioners (GPs) are reimbursed. It claimed that the General Practice Access Scheme (GPAS) would benefit all Australians by providing more affordable access to GP services and improved access to free GP consultations for concession cardholders. This article examines the likely impacts of the GPAS, focusing on the proposed changes to bulk billing and payments to GPs. It examines the current spatial distribution of bulk billing and discusses how the package changes the incentives for GPs to charge patients and likely impacts on GP income, patient copayments and bulk billing rates.
Moving towards an Improved Microsimulation Model of the Australian Pharmaceutical Benefits Scheme
Authors: Brown Laurie , Abello Annie , Phillips Ben , Harding Ann 
Published: March 2004

AbstractFinding ways of curbing government expenditure on the Pharmaceutical Benefits Scheme (PBS) while maintaining social equity and access to ‘essential’ medicines is at the centre of ongoing public debate. This article describes a microsimulation model of the PBS that simulates current and future use and costs of PBS medicines under existing and different PBS policy settings, and estimates the distributional effects of policy changes. The article outlines future developments that will extend the current model to include health outcomes. Adding health outcomes will enable the debate on PBS sustainability to be advanced beyond the prevailing cost‐containment mentality to consider not only the costs of pharmaceutical use but also the benefits that result from the use of these medicines.
Measurement of the Quality of Life for Economic Evaluation and the Assessment of Quality of Life (AQoL) Mark 2 Instrument
Authors: Richardson Jeff , Atherton Day Neil , Peacock Stuart , Iezzi Angelo 
Published: March 2004

AbstractIncluding the quality of life in the economic assessment of health and medical services is well established in the literature and a number of multi‐attribute utility (MAU) instruments are available which purport to measure health state utilities. One of these, the Assessment of Quality of Life (AQoL) instrument was developed in Australia and uses Australian importance weights. The present article discusses some of the methodological problems encountered by existing instruments. It outlines the construction of the AQoL Mark 2 and the methodological innovations which have attempted to overcome some of these problems.Technical and other details may be obtained in Richardson et al. (2003a, 2003b, 2003c) and Peacock et al. (2003). These papers may be accessed from the Health Economics Unit web site at 〈http://heu.buseco.monash.edu.au〉.
Potential Growth and Inflation: Estimates for Australia, the United States and Canada
Authors: Dungey Mardi , Pitchford John 
Published: March 2004

AbstractEstimates of potential output growth for Australia, the United States and Canada are presented and analysed in this article. We define potential growth as that growth rate consistent with a steady (domestic component of the) inflation rate (SIRG). At around 4 per cent per annum, Australia's SIRG has been relatively stable for the past 30 years, which seems inconsistent with the view that wide‐ranging microeconomic reform in the 1990s raised growth potential. However, we show that the reduction in employment growth in Australia from the 1980s to the 1990s may account for the absence of a rise in potential growth. In Canada and the United States the SIRGs are closer to 3 per cent, and we explore the reasons why potential growth estimates are higher for Australia than for North America. We also discuss why Australia's growth averaged less than its potential in the 1980s and 1990s and the possible use of our estimates for monetary policy purposes.
The Dendroecological Potential of Eucalyptus Camaldulensis Dehnhardt (River Red Gum) from the Barmah Forest, Victoria, Australia
Authors: Argent R. M. , Mcmahon T. A. , Bowler J. M. , Finlayson B. L. 
Published: March 2004

AbstractThe study of tree rings has been used for over 100 years to inform climatic and geomorphological reconstructions. In mainland Australia, no tree species are currently recognised as providing reliable sources for such studies over extensive areas. Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods. The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies. This study initially examines the microstructure of samples of E. camaldulensis taken from the Barmah Forest to assess the applicability of the species to dendroecological investigation. It is found that samples of the species exhibit ring‐like structures, although there are areas of the samples that contain zones of growth without clear ring boundaries. The patterns of growth rings and zones are found to be common to many trees at a site, although the level of variability of pattern from tree to tree is high. Options for future development of the approach described here are to combine ring studies with isotopic‐based analysis to provide a combination of tree age and climatic history.
Critical Bioethics: Beyond the Social Science Critique of Applied Ethics
Authors: Hedgecoe Adam M. 
Published: March 2004

ABSTRACTThis article attempts to show a way in which social science research can contribute in a meaningful and equitable way to philosophical bioethics. It builds on the social science critique of bioethics present in the work of authors such as Renée Fox, Barry Hoffmaster and Charles Bosk, proposing the characteristics of a critical bioethics that would take social science seriously.The social science critique claims that traditional philosophical bioethics gives a dominant role to idealised, rational thought, and tends to exclude social and cultural factors, relegating them to the status of irrelevancies. Another problem is the way in which bioethics assumes social reality divides down the same lines/categories as philosophical theories.Critical bioethics requires bioethicists to root their enquires in empirical research, to challenge theories using evidence, to be reflexive and to be sceptical about the claims of other bioethicists, scientists and clinicians. The aim is to produce a rigorous normative analysis of lived moral experience.
Doctors in the Decent Society: Torture, Ill‐Treatment and Civic Duty
Authors: Gross Michael L. 
Published: March 2004

ABSTRACTHow should physicians act when faced with corporal punishment, such as amputation, or torture? In most cases, the answer is clear: international law, UN resolutions and universal codes of medical ethics absolutely forbid physicians from countenancing torture and corporal punishment in any form. An acute problem arises, however, in decent societies, but not necessarily liberal states, that are, nonetheless, welcome in the world community. The decent society is often governed, in whole or in part, by religious laws, and while these states abridge various human rights they are peace loving, generally tolerant, and offer their citizens wide avenues for political participation. Under these circumstances the prohibition against corporal punishment and torture weakens, often compelling physicians to participate. This is true in two cases. In Rawls’ hypothetical nation of Kazanistan, Islamic law is the order of the day, and amputations and corporal punishment play an integral part in the execution of traditional Islamic justice. In Israel, torture is sometimes used to elicit the information needed to thwart impending terror attacks. In each case, a physician's participation is essential. In light of the near universal condemnation that accompanies torture and corporal punishment, physicians can only appeal to norms anchored in collective well‐being and concern for life that override respect for human dignity in these societies. Western societies have consistently rejected this reasoning, but it is part and parcel of life in the decent society.
Characterization of Toxin A-Negative, Toxin B-Positive
Clostridium difficile
Isolates from Outbreaks in Different Countries by Amplified Fragment Length Polymorphism and PCR Ribotyping
Authors: van den Berg Renate J. , Claas Eric C. J. , Oyib Duddy H. , Klaassen Corné H. W. , Dijkshoorn Lenie , Brazier Jon S. , Kuijper Ed J. 
Published: March 2004

ABSTRACT

Clinical
Clostridium difficile
isolates of patients with diarrhea or pseudomembranous colitis usually produce both toxin A and toxin B, but an increasing number of reports mention infections due to toxin A-negative, toxin B-positive (A
−
/B
+
) strains. Thirty-nine clinical toxin A
−
/B
+
isolates, and 12 other unrelated isolates were obtained from Canada, the United States, Poland, the United Kingdom, France, Japan, and The Netherlands. The isolates were investigated by high-resolution genetic fingerprinting by use of amplified fragment length polymorphism (AFLP) and two well-described PCR ribotyping methods. Furthermore, the toxin profile and clindamycin resistance were determined. Reference strains of
C. difficile
representing 30 known serogroups were also included in the analysis. AFLP discriminated 29 types among the reference strains, whereas the two PCR ribotyping methods distinguished 25 and 26 types. The discriminatory power of AFLP and PCR ribotyping among 12 different unrelated isolates was similar. Typing of 39 toxin A
−
/B
+
isolates revealed 2 AFLP types and 2 and 3 PCR ribotypes. Of 39 toxin A
−
/B
+
isolates, 37 had PCR ribotype 017/20 and AFLP type 20 (95%). A deletion of 1.8 kb was seen in 38 isolates, and 1 isolate had a deletion of approximately 1.7 kb in the
tcdA
gene, which encodes toxin A. Clindamycin resistance encoded by the
erm
(B) gene was found in 33 of 39 toxin A
−
/B
+
isolates, and in 2 of the 12 unrelated isolates (
P
< 0.001, chi-square test). We conclude that clindamycin-resistant
C. difficile
toxin A
−
/B
+
strain (PCR ribotype 017/20, AFLP type 20, serogroup F) has a clonal worldwide spread.
Microarray-Based Identification of Bacteria in Clinical Samples by Solid-Phase PCR Amplification of 23S Ribosomal DNA Sequences
Authors: Mitterer Georg , Huber Martin , Leidinger Ernst , Kirisits Claudia , Lubitz Werner , Mueller Manfred W. , Schmidt Wolfgang M. 
Published: March 2004

ABSTRACTThe rapid identification of the bacteria in clinical samples is important for patient management and antimicrobial therapy. We describe a DNA microarray-based PCR approach for the quick detection and identification of bacteria from cervical swab specimens from mares. This on-chip PCR method combines the amplification of a variable region of bacterial 23S ribosomal DNA and the simultaneous sequence-specific detection on a solid phase. The solid phase contains bacterial species-specific primers covalently bound to a glass support. During the solid-phase amplification reaction the polymerase elongates perfectly matched primers and incorporates biotin-labeled nucleotides. The reaction products are visualized by streptavidin-cyanine 5 staining, followed by fluorescence scanning. This procedure successfully identified from pure cultures 22 bacteria that are common causes of abortion and sterility in mares. Using the on-chip PCR method, we also tested 21 cervical swab specimens from mares for the presence of pathogenic bacteria and compared the results with those of conventional bacteriological culture methods. Our method correctly identified the bacteria in 12 cervical swab samples, 8 of which contained more than one bacterial species. Due to the higher sensitivity of the on-chip PCR, this method identified bacteria in five cervical swab samples which were not detected by the conventional identification procedure. Our results show that this method will have great potential to be incorporated into the routine microbiology laboratory.
Evaluation of Recombinant Fragments of
Entamoeba histolytica
Gal/GalNAc Lectin Intermediate Subunit for Serodiagnosis of Amebiasis
Authors: Tachibana Hiroshi , Cheng Xun-Jia , Masuda Gohta , Horiki Noriyuki , Takeuchi Tsutomu 
Published: March 2004

ABSTRACT

We have recently identified a 150-kDa surface antigen of
Entamoeba histolytica
as an intermediate subunit (Igl) of galactose- and
N
-acetyl
-d-
galactosamine-inhibitable lectin, which is a cysteine-rich protein consisting of 1,101 amino acids (aa) and containing multiple CXXC motifs in amino acid sequences. In the present study, full-length Igl except for the signal sequences (aa 14 to 1088) and three fragments of Igl—the N-terminal part (aa 14 to 382), the middle part (aa 294 to 753), and the C-terminal part (aa 603 to 1088)—were prepared in
Escherichia coli
, and the reactivity of these recombinant proteins with sera from patients with amebiasis was examined by means of enzyme-linked immunosorbent assay (ELISA). Sera from 57 symptomatic patients with amebic liver abscess or amebic colitis, sera from 15 asymptomatic cyst passers, sera from 40 individuals with other protozoan infections, and sera from 50 healthy controls were used. The sensitivity and specificity of the recombinant full-length Igl in the ELISA were 90 and 94%, respectively. When three fragments were used as antigens in the ELISA, the sensitivities were 56% in the N terminus, 92% in the middle part, and 97% in the C terminus. The specificities of the three antigens were 96% in the N terminus and 99% in both the middle and C-terminal fragments. These results demonstrate that Igl is well recognized in not only symptomatic but also asymptomatic patients with
E. histolytica
infection and that the carboxyl terminus of Igl is an especially useful antigen for the serodiagnosis of amebiasis.
Molecular Cloning, Expression, and Serological Evaluation of an 8-Kilodalton Subunit of Antigen B from
Echinococcus multilocularis
Authors: Mamuti Wulamu , Yamasaki Hiroshi , Sako Yasuhito , Nakao Minoru , Xiao Ning , Nakaya Kazuhiro , Sato Naoki , Vuitton Dominique A. , Piarroux Renaud , Lightowlers Marshall W. , Craig Philip S. , Ito Akira 
Published: March 2004

ABSTRACT

Full-length cDNA and genomic DNA encoding an 8-kDa subunit of antigen B from
Echinococcus multilocularis
(designated EmAgB8/1) were isolated from an
E. multilocularis
metacestode cDNA library and a protoscolex genomic DNA library, respectively. The open reading frame of the cDNA clone encodes a polypeptide comprising 85 amino acids with a 20-amino-acid NH
2
-terminal signal sequence, which was confirmed following N-terminal sequencing of the native antigen. Reverse transcription-PCR analysis revealed that the clone encoding EmAgB8/1 is predominantly transcribed in larval
E. multilocularis
. The gene consists of two exons (encoding the signal sequence and mature protein) separated by a 91-bp intron. The mature form was expressed in
Escherichia coli
, and its antigenic reactivity was compared with that of a counterpart, an 8-kDa subunit of antigen B from
Echinococcus granulosus
(EgAgB8/1) by Western blotting and enzyme-linked immunosorbent assay (ELISA) with serum samples from patients confirmed to have cystic echinococcosis (CE) and alveolar echinococcosis (AE). Recombinant EmAgB8/1 showed positive reactions in Western blots with 81.3% (65 of 80) of serum samples from CE patients and 40.6% (26 of 64) of serum samples from AE patients, while recombinant EgAgB8/1 showed positive reactions with 86% (43 of 50) and 42% (19 of 45) of the serum samples from these CE and AE patients, respectively. By the ELISA, both EmAgB8/1 and EgAgB8/1 exhibited similar positive reactions with 88% (44 of 50) of serum samples from CE patients and 37.8% (17 of 45) serum samples from AE patients. Statistical analysis revealed that the sensitivity of EmAgB8/1 was comparable to that of EgAgB8/1 for the serodiagnosis of echinococcal diseases. There was no cross-reaction with sera from patients with cysticercosis, which often cross-react when native antigens are used for serodiagnosis.