bluuebunny/crossref_metadata_2025_split huggingface dataset:
EPR study of nitroxides formed from the reaction of nitric oxide with photolyzed amides
Authors: Wang Fan , Jin Jing , Wu Longmin 
Published: August 2003

AbstractFree radicals generated from UV irradiation of simple aliphatic amides in anaerobic and nitric oxide (NO)‐saturated liquid mixtures or solutions gave EPR spectra of nitroxides. The application of isotopic effects to EPR spectra and the generation of radicals by transient radical attack on substrate molecules or by photolysing amine or acetoin were used to help identify photochemically produced radicals from the amides. The aliphatic amides used were formamide, acetamide and their N‐methyl‐ or deuterium‐substituted derivatives. Transient radicals used to attack the amides via hydrogen‐atom abstraction were generated from the initiator AIBN or AAPH. The observation of various nitroxides indicates the reactivity of NO for trapping acyl, carbamoyl and other carbon‐centered radicals. Possibly mechanistic pathways diagnosed with this trap are proposed. Copyright © 2003 John Wiley & Sons, Ltd.
Optimal pricing in a hazard rate model of demand
Authors: Sethi Suresh P. , Bass Frank M. 
Published: August 2003

AbstractOptimal control theory is employed to derive explicitly the optimal (profit‐maximizing) price of a durable new product over time. The sales rate dynamics depends on the product price and on the unsold portion of the market. Specifically, the hazard rate (i.e. the probability of a purchase by a new customer) increases as the price decreases in a linear fashion. It is shown that both the price and sales rate decline over time for finite horizon problems with or without discounting. In the discounted infinite horizon case, the price remains constant over time. When there is no discounting in the infinite horizon case, there does not exist an optimal solution. However, it is possible in this case to attain a profit level which is arbitrarily close to the theoretical, albeit unattainable, maximum level profit. Economic interpretations are provided for the various quantities that arise in the course of solving the optimal pricing problem. Copyright © 2003 John Wiley & Sons, Ltd.
Retropharyngeal and mediastinal abscess following adenoidectomy
Authors: Tuerlinckx David , Bodart Eddy , Lawson Georges , De Wispelaere Jean‐François , de Bilderling Georges 
Published: August 2003

AbstractAdenoidectomy is one of the most common surgical procedures in children. On rare occasions it can be complicated by a retropharyngeal abscess (RA). We report the case of a 9‐year‐old girl with an RA extending to the mediastinum following adenoidectomy. The mediastinal collection was successfully treated with computed tomography‐guided percutaneous drainage to avoid extensive surgical procedure. Surgeons should be aware of these dramatic complications and should avoid overzealous surgery in the removal of the adenoid tissue. Pediatr Pulmonol. 2003; 36:257–258. © 2003 Wiley‐Liss, Inc.
Pulmonary mucus: Pediatric perspective
Authors: Rogers Duncan F. 
Published: August 2003

AbstractAirway mucus hypersecretion is a clinical feature of a number of childhood diseases, including asthma and bronchitis‐associated conditions. However, compared with adults, there is relatively scarce information concerning mucus pathophysiology in respiratory diseases in children. The available evidence indicates many similarities between adult and childhood respiratory hypersecretory conditions, including goblet‐cell hyperplasia and submucosal gland hypertrophy, and airway mucus plugging in asthma. Consequently, it is likely that treatments that are effective in adults would be effective in children. Numerous therapeutic targets are linked to the pathophysiology of airway mucus hypersecretion in experimental models and adults with respiratory disease. Whether or not these same targets are relevant in children is for the most part unclear. These targets include the inflammatory cells mediating the inflammatory response that generates the hypersecretory phenotype, and highly specific cellular elements such as epidermal growth factor receptor tyrosine kinase and calcium‐activated chloride (CACL) channels. Identification of these factors is linked with the development of different classes of pharmacotherapeutic molecules directed at these targets. Compounds with a broader spectrum of anti‐inflammatory activity are likely to be more effective than compounds with restricted activity. However, certain highly specific targets, such as human CACL1 channels, appear to be strongly associated with the development of an airway hypersecretory phenotype. Data from current clinical trials in adults with blockers of these specific targets are awaited with great interest. The hope is that, if effective, pediatric trials with these compounds could be initiated with a view to alleviation of the clinical impact of airway mucus hypersecretion in children. A significant challenge to the therapeutic progression of these new compounds is effective delivery to the airways in children, with the research effort into development of new compounds matched by advances in inhaler design. Pediatr Pulmonol. 2003; 36:178–188. © 2003 Wiley‐Liss, Inc.
An architecture for an intelligent support system for design validation and manufacturing of aerospace components
Authors: Lambrinoudakis Costas , Maistros George , Bofilios Dimitri , Darzentas John 
Published: August 2003

AbstractThis paper presents the architecture of a multi‐agent system that aims to support the design and manufacturing processes of composite material components for the aerospace, automobile, ship and other industries. The major goals are to accelerate the design process while minimising cost; support users in selecting the optimum material in terms of its properties, cost and environmental impact; and enhance the efficiency of the component manufacturing phase by extending the decision support capabilities of the existing real‐time monitoring software. An important requirement for achieving these objectives is to enable the more efficient utilisation of existing distributed information on composite materials. To this end, state‐of‐the‐art advances in metadata concepts were adopted and extended. By implementing metadata structures for each data category available, the searching and retrieval mechanisms are improved both in terms of speed and usage. In addition, large amounts of knowledge about the design and manufacturing processes themselves are incorporated into a multi‐agent environment in order to enhance the ability to support the user groups involved in the various stages of component design and manufacturing. In order to present the system architecture here, an example from the aerospace industry has been used.
Identification of
Streptococcus sanguinis
with a PCR-Generated Species-Specific DNA Probe
Authors: Li Yihong , Pan Yaping , Qi Fengxia , Caufield Page W. 
Published: August 2003

ABSTRACT

The objective of the present study was to design a PCR-generated DNA probe and determine the specificity of the probe for the identification of clinical isolates of
Streptococcus sanguinis
. To do this, we examined over 200 arbitrarily primed PCR (AP-PCR) amplicon patterns obtained with DNA from clinical isolates of
S. sanguinis
. A 1.6-kb DNA amplicon that was common to all AP-PCR profiles was extracted from agarose gels and then cloned and sequenced. A search for a similar sequence in the GenBank database with the BLASTN program revealed that the 1.6-kb DNA fragment comprised an intergenic region between two housekeeping genes,
uncC
(proton-translocating ATPase) and
murA
(UDP-
N
-acetylglucosamine enolpyruvyl transferase). Three digoxigenin-labeled DNA probes were synthesized on the basis of the sequence of the 1.6-kb fragment: the sequence of probe SSA-1 contained the proton-translocating ATPase (
uncC
) and the entire intergenic region, the sequence of probe SSA-2 contained only the intergenic region, and the sequence of probe SSA-3 contained an internal region of the
murA
gene. Dot blot hybridization showed that the three probes displayed signals for hybridization to both
S. sanguinis
strain ATCC 10556 and the
S. sanguinis
clinical isolates. Probe SSA-1, however, hybridized to DNA from
S. oralis
and
S. mitis.
Probe SSA-3 hybridized to DNA from
S. gordonii
,
S. mitis
,
S. oralis
,
S. parasanguinis
, and
S. vestibularis
. The probe SSA-2-specific intergenic region appeared to be specific for
S. sanguinis
. The results from this study suggest that probe SSA-2 may serve as a species-specific DNA probe for the identification of clinical isolates of
S. sanguinis
.
Comparison of the Directigen Flu A+B Test, the QuickVue Influenza Test, and Clinical Case Definition to Viral Culture and Reverse Transcription-PCR for Rapid Diagnosis of Influenza Virus Infection
Authors: Ruest Annie , Michaud Sophie , Deslandes Sylvie , Frost Eric H. 
Published: August 2003

ABSTRACT
The diagnostic performances of the clinical case definition of influenza virus infection based on the combination of fever and cough and of two rapid influenza diagnostic tests, the Directigen Flu A+B test (Directigen; BD Diagnostic Systems, Sparks, Md.) and the QuickVue influenza test (QuickVue; Quidel, San Diego, Calif.), were compared to those of viral culture and an in-house reverse transcription (RT)-PCR during the 2000-2001 flu season. Two hundred consecutive nasopharyngeal aspirates were analyzed from 192 patients, including 122 adults and 70 children. Viral culture identified influenza virus A in 16 samples and influenza virus B in 55 samples, whereas RT-PCR identified influenza virus A in 21 samples and influenza virus B in 64 samples. When RT-PCR was used as the reference standard, the likelihood ratios for a positive test were 40.0 for Directigen, 8.6 for QuickVue, and 1.4 for the combination of fever and cough, whereas the likelihood ratios for a negative test were 0.22, 0.16, and 0.48, respectively. Our study suggests that (i) the poor specificity (35 to 58%) and the poor positive predictive value (41 to 60%) of the clinical case definition of influenza preclude its use for prediction of influenza virus infections during epidemics, especially when infection control decision making in the hospital setting is considered; (ii) Directigen has a higher diagnostic yield than QuickVue but is associated with a larger number of invalid results; (iii) the sensitivities of the rapid diagnostic tests are significantly lower with samples from adults than with samples from children, with the rates of false-negative results reaching up to 29%; and (iv) RT-PCR detects more cases of influenza than viral culture, and this greater accuracy makes it a more useful reference standard.
Evaluation of the MagNA Pure LC Instrument for Extraction of Hepatitis C Virus RNA for the COBAS AMPLICOR Hepatitis C Virus Test, Version 2.0
Authors: Germer Jeffrey J. , Lins Michele M. , Jensen Monica E. , Harmsen W. Scott , Ilstrup Duane M. , Mitchell P. Shawn , Cockerill Franklin R. , Patel Robin 
Published: August 2003

ABSTRACT
The COBAS AMPLICOR system has played a major role in the transition of molecular diagnostics from research to routine clinical laboratory use by automating the nucleic acid amplification and detection processes. However, sample preparation remains a labor-intensive portion of the procedure. In this study, we evaluated the performance of the COBAS AMPLICOR Hepatitis C Virus Test, version 2.0 (Roche Molecular Systems, Branchburg, N.J.) following manual hepatitis C virus (HCV) RNA extraction versus automated extraction with the MagNA Pure LC instrument (Roche Applied Science, Indianapolis, Ind.). Parallel replicate testing was performed with standard dilutions of 100, 75, 60, and 0 HCV IU/ml and 153 clinical specimens. An analytical sensitivity of 75 IU/ml was achieved with either the manual or the standard-volume (200 μl) automated extraction methodologies (25 of 26 [96.2%]; 95% confidence interval [95% CI], 80.4 to 99.9), whereas the clinical sensitivity and specificity were both 100% with either extraction method. A large-volume (1 ml) automated extraction method was also evaluated with standard dilutions of 40, 25, 10, and 0 IU/ml and the same 153 clinical specimens. The analytical sensitivity of the COBAS AMPLICOR assay with the large-volume extraction method was 25 HCV IU/ml (26 of 26 [100%]; 95% CI, 86.8 to 100), whereas the clinical sensitivity and specificity were both 100%. The MagNA Pure LC instrument is a versatile, labor-saving platform capable of integration with minimal modification of the existing assay procedure. The increased sensitivity of the COBAS AMPLICOR Hepatitis C Virus Test, version 2.0 performed in conjunction with large-volume HCV RNA extraction may be important in HCV diagnostic testing as new therapeutic strategies evolve.
Mycobacterial Interspersed Repetitive Unit Typing ofMycobacterium tuberculosisCompared to IS6110-Based Restriction Fragment Length Polymorphism Analysis for Investigation of Apparently Clustered Cases of Tuberculosis
Authors: Hawkey Peter M. , Smith E. Grace , Evans Jason T. , Monk Philip , Bryan Gerry , Mohamed Huda H. , Bardhan Madhu , Pugh R. Nicholas 
Published: August 2003

ABSTRACTAn evaluation of the utility of IS6110-based restriction fragment length polymorphism (RFLP) typing compared to a combination of variable number tandem repeat (VNTR) typing and mycobacterial interspersed repetitive unit (MIRU) typing was undertaken. A total of 53 patient isolates ofMycobacterium tuberculosisfrom four presumed episodes of cross-infection were examined. Genomic DNA was extracted from the isolates by a cetyl trimethylammonium bromide method. The number of copies of tandem repeats of the five loci ETRAto ETREand 12 MIRU loci was determined by PCR amplification and agarose gel electrophoresis of the amplicons. VNTR typing identified the major clusters of strains in the three investigations in which they occurred (each representing a different evolutionary clade: 32333, 42235, and 32433). The majority of unrelated isolates (by epidemiology and RFLP typing) were also identified by VNTR typing. The concordance between the RFLP and MIRU typing was complete, with the exception of two isolates with RFLP patterns that differed by one band each from the rest of the major epidemiologically linked groups of isolates in investigation A. All of these isolates had identical MIRU and VNTR types. A further pair of isolates differed in the number of tandem repeat copies at two MIRU alleles but had identical RFLP patterns. The speed of the combined VNTR and MIRU typing approach enabled results for some of the investigations to be supplied in “real time,” influencing choices in contact tracing. The ease of comparison of results of MIRU and VNTR typing, which are recorded as single multidigit numbers, was also found to greatly facilitate investigation management and the communication of results to health care professionals.
Development and Evaluation of a Blocking Enzyme-Linked Immunosorbent Assay for Detection of Avian Metapneumovirus Type C-Specific Antibodies in Multiple Domestic Avian Species
Authors: Turpin Elizabeth A. , Lauer Dale C. , Swayne David E. 
Published: August 2003

ABSTRACT
The first cases of infection caused by avian metapneumoviruses (aMPVs) were described in turkeys with respiratory disease in South Africa during 1978. The causative agent was isolated and identified as a pneumovirus in 1986. aMPVs have been detected in domestic nonpoultry species in Europe, but tests for the detection of these viruses are not available in the United States. To begin to understand the potential role of domestic ducks and geese and wild waterfowl in the epidemiology of aMPV, we have developed and evaluated a blocking enzyme-linked immunosorbent assay (bELISA) for the detection of aMPV type C (aMPV-C)-specific antibodies. This assay method overcomes the species-specific platform of indirect ELISAs to allow detection of aMPV-C-specific antibodies from potentially any avian species. The bELISA was initially tested with experimental turkey serum samples, and the results were found to correlate with those of virus neutralization assays and indirect enzyme-linked immunosorbent assay (iELISA). One thousand serum samples from turkey flocks in Minnesota were evaluated by our bELISA, and the level of agreement of the results of the bELISA and those of the iELISA was 94.9%. In addition, we were able to show that the bELISA could detect aMPV-C-specific antibodies from experimentally infected ducks, indicating its usefulness for the screening of serum samples from multiple avian species. This is the first diagnostic assay for the detection of aMPV-C-specific antibodies from multiple avian species in the United States.
Genomic Approach to Identification of
Mycobacterium bovis
Diagnostic Antigens in Cattle
Authors: Aagaard Claus , Govaerts Marc , Meng Okkels Limei , Andersen Peter , Pollock John M. 
Published: August 2003

ABSTRACT

Differential delayed-type hypersensitivity skin testing with tuberculin purified protein derivatives from
Mycobacterium bovis
and
M. avium
is the standard for diagnosing bovine tuberculosis. However, improved tests based on defined, specific antigens are urgently needed. In the present study, a combination of bioinformatics, molecular biology, and bovine models of infection were used to screen mycobacterial proteins for their potential as diagnostic reagents which could be used in a whole-blood assay for diagnosis of tuberculosis. Initial screening of 28 proteins selected in silico and expressed as recombinants in
Escherichia coli
indicated that CFP-10, ESAT-6, TB27.4, TB16.2, TB15.8, and TB10.4 induced strong gamma interferon responses in experimentally infected cattle. A more thorough investigation over time in two groups of animals infected with a high (10
6
CFU) and a low (10
4
CFU) dose of
M. bovis
revealed that, for both groups, the strength of the in vitro response to individual antigens varied greatly over time. However, combining the results for ESAT-6, CFP-10, and TB27.4, possibly supplemented with TB10.4, gave sensitivities at different infection stages close to those obtained with
M. bovis
purified protein derivative. Importantly, while responsiveness to ESAT-6 and CFP-10 correlated strongly for individual samples, the same was not the case for ESAT-6 and TB27.4 responsiveness. The results suggest that combinations of specific antigens such as these have great potential in development of optimized diagnostic systems for bovine tuberculosis.
Geographic Diversity among Genotypes of
Entamoeba histolytica
Field Isolates
Authors: Haghighi Ali , Kobayashi Seiki , Takeuchi Tsutomu , Thammapalerd Nitaya , Nozaki Tomoyoshi 
Published: August 2003

ABSTRACT

It has been known that only 5 to 10% of those infected with
Entamoeba histolytica
develop symptomatic disease. However, the parasite and the host factors that determine the onset of disease remain undetermined. Molecular typing by using polymorphic genetic loci has been proven to aid in the close examination of the population structure of
E. histolytica
field isolates in nature. In the present study, we analyzed the genetic polymorphisms of two noncoding loci (locus 1-2 and locus 5-6) and two protein-coding loci (chitinase and serine-rich
E. histolytica
protein [SREHP]) among 79 isolates obtained from different geographic regions, mainly Japan, Thailand, and Bangladesh. When the genotypes of the four loci were combined for all isolates that we have analyzed so far (overlapping isolates from mass infection events were excluded), a total of 53 different genotypes were observed among 63 isolates. The most remarkable and extensive variations among the four loci was found in the SREHP locus; i.e., 34 different genotypes were observed among 52 isolates. These results demonstrate that
E. histolytica
has an extremely complex genetic structure independent of geographic location. Our results also show that, despite the proposed transmission of other sexually transmitted diseases, including human immunodeficiency virus infection, from Thailand to Japan, the spectra of the genotypes of the
E. histolytica
isolates from these two countries are distinct, suggesting that the major
E. histolytica
strains prevalent in Japan at present were likely introduced from countries other than Thailand. Although the genetic polymorphism of the SREHP locus was previously suggested to be closely associated with the clinical presentation, e.g., colitis or dysentery and liver abscess, no association between the clinical presentation and the SREHP genotype at either the nucleotide or the predicted amino acid level was demonstrated.
Presence of Activatable Shiga Toxin Genotype (
stx
2d
) in Shiga Toxigenic
Escherichia coli
from Livestock Sources
Authors: Gobius Kari S. , Higgs Glen M. , Desmarchelier Patricia M. 
Published: August 2003

ABSTRACT

Stx2d is a recently described Shiga toxin whose cytotoxicity is activated 10- to 1,000-fold by the elastase present in mouse or human intestinal mucus. We examined Shiga toxigenic
Escherichia coli
(STEC) strains isolated from food and livestock sources for the presence of activatable
stx
2d
. The
stx
2
operons of STEC were first analyzed by PCR-restriction fragment length polymorphism (RFLP) analysis and categorized as
stx
2
,
stx
2c vha
,
stx
2c vhb
, or
stx
2d EH250
. Subsequently, the
stx
2c vha
and
stx
2c vhb
operons were screened for the absence of a
Pst
I site in the
stx
2A
subunit gene, a restriction site polymorphism which is a predictive indicator for the
stx
2d
(activatable) genotype. Twelve STEC isolates carrying putative
stx
2d
operons were identified, and nucleotide sequencing was used to confirm the identification of these operons as
stx
2d
. The complete nucleotide sequences of seven representative
stx
2d
operons were determined. Shiga toxin expression in
stx
2d
isolates was confirmed by immunoblotting.
stx
2d
isolates were induced for the production of bacteriophages carrying
stx
. Two isolates were able to produce bacteriophages φ1662a and φ1720a carrying the
stx
2d
operons. RFLP analysis of bacteriophage genomic DNA revealed that φ1662a and φ1720a were highly related to each other; however, the DNA sequences of these two
stx
2d
operons were distinct. The STEC strains carrying these operons were isolated from retail ground beef. Surveillance for STEC strains expressing activatable Stx2d Shiga toxin among clinical cases may indicate the significance of this toxin subtype to human health.
Evolution of Sporadic Isolates of Methicillin-Resistant
Staphylococcus aureus
(MRSA) in Hospitals and Their Similarities to Isolates of Community-Acquired MRSA
Authors: Aires de Sousa M. , de Lencastre H. 
Published: August 2003

ABSTRACT

Forty-one methicillin-resistant
Staphylococcus aureus
(MRSA) hospital isolates that clearly differed from the six major pandemic clones of MRSA in pulsed-field gel electrophoresis type,
mecA
and Tn
554
polymorphism, and epidemic behavior were selected from an international strain collection for more detailed characterization.
SpaA
typing, multilocus sequence typing, and SCC
mec
(staphylococcal cassette chromosome
mec
) typing demonstrated extensive diversity among these sporadic isolates both in genetic background and also in the structure of the associated SCC
mec
elements. Nevertheless, the isolates could be grouped into restricted clonal complexes by using the BURST (i.e., based upon related sequence types) program algorithm, which predicted that most sporadic MRSA isolates evolved from pandemic MRSA clones. Several of the sporadic MRSA resembled community-acquired MRSA isolates in properties that included a relatively limited multiresistance pattern, faster growth rates, diversity of genetic backgrounds, and a frequent association with SCC
mec
type IV.