bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-Throughput Screen for Poly-3-Hydroxybutyrate in
Escherichia coli
and
Synechocystis
sp. Strain PCC6803
Authors: Tyo Keith E. , Zhou Hang , Stephanopoulos Gregory N. 
Published: May 2006

ABSTRACT

A novel, quantitative method for detecting poly-3-hydroxybutyrate (PHB) amounts in viable cells was developed to allow for high-throughput screening of mutant libraries. The staining technique was demonstrated and optimized for the cyanobacterium
Synechocystis
sp. strain PCC6803 and the eubacterium
Escherichia coli
to maximize the fluorescence difference between PHB-accumulating and control cells by flow cytometry. In
Synechocystis
, the level of nonspecific dye binding was reduced by using nonionic stain buffer that allowed quantitation of fluorescence levels. In
E. coli
, the use of a mild sucrose shock facilitated uptake of Nile red without significant loss of viability. The optimized staining protocols yielded a linear response for the mean fluorescence against (chemically measured) PHB. The staining protocols are novel methods useful in the high-throughput evaluation of combinatorial libraries of
Synechocystis
and
E. coli
using fluorescence-activated cell sorting to identify mutants with increased PHB-accumulating properties.
Occurrence of Natural
Bacillus thuringiensis
Contaminants and Residues of
Bacillus thuringiensis
-Based Insecticides on Fresh Fruits and Vegetables
Authors: Frederiksen Kristine , Rosenquist Hanne , Jørgensen Kirsten , Wilcks Andrea 
Published: May 2006

ABSTRACT

A total of 128
Bacillus cereus
-like strains isolated from fresh fruits and vegetables for sale in retail shops in Denmark were characterized. Of these strains, 39% (50/128) were classified as
Bacillus thuringiensis
on the basis of their content of
cry
genes determined by PCR or crystal proteins visualized by microscopy. Random amplified polymorphic DNA analysis and plasmid profiling indicated that 23 of the 50
B. thuringiensis
strains were of the same subtype as
B. thuringiensis
strains used as commercial bioinsecticides. Fourteen isolates were indistinguishable from
B. thuringiensis
subsp.
kurstaki
HD1 present in the products Dipel, Biobit, and Foray, and nine isolates grouped with
B. thuringiensis
subsp.
aizawai
present in Turex. The commercial strains were primarily isolated from samples of tomatoes, cucumbers, and peppers. A multiplex PCR method was developed to simultaneously detect all three genes in the enterotoxin hemolysin BL (HBL) and the nonhemolytic enterotoxin (NHE), respectively. This revealed that the frequency of these enterotoxin genes was higher among the strains indistinguishable from the commercial strains than among the other
B. thuringiensis
and
B. cereus
-like strains isolated from fruits and vegetables. The same was seen for a third enterotoxin, CytK. In conclusion, the present study strongly indicates that residues of
B. thuringiensis
-based insecticides can be found on fresh fruits and vegetables and that these are potentially enterotoxigenic.
Assessment of Toluene/Biphenyl Dioxygenase Gene Diversity in Benzene-Polluted Soils: Links between Benzene Biodegradation and Genes Similar to Those Encoding Isopropylbenzene Dioxygenases
Authors: Witzig Robert , Junca Howard , Hecht Hans-Jürgen , Pieper Dietmar H. 
Published: May 2006

ABSTRACT

The PCR-single-strand conformation polymorphism (SSCP) technique was used to assess the diversity and distribution of Rieske nonheme iron oxygenases of the toluene/biphenyl subfamily in soil DNA and bacterial isolates recovered from sites contaminated with benzene, toluene, ethylbenzene, and xylenes (BTEX). The central cores of genes encoding the catalytic α subunits were targeted, since they are responsible for the substrate specificities of these enzymes. SSCP functional genotype fingerprinting revealed a substantial diversity of oxygenase genes in three differently BTEX-contaminated soil samples, and sequence analysis indicated that in both the soil DNA and the bacterial isolates, genes for oxygenases related to the isopropylbenzene (cumene) dioxygenase branch of the toluene/biphenyl oxygenase subfamily were predominant among the detectable genotypes. The peptide sequences of the two most abundant α subunit sequence types differed by only five amino acids (residues 258, 286, 288, 289, and 321 according to numbering in cumene dioxygenase α subunit CumA1 of
Pseudomonas fluorescens
IP01). However, a strong correlation between sequence type and substrate utilization pattern was observed in isolates harboring these genes. Two of these residues were located at positions contributing, according to the resolved crystal structure of cumene dioxygenase from
Pseudomonas fluorescens
IP01, to the inner surface of the substrate-binding pocket. Isolates containing an α subunit with isoleucine and leucine at positions 288 and 321, respectively, were capable of degrading benzene and toluene, whereas isolates containing two methionine substitutions were found to be incapable of degrading toluene, indicating that the more bulky methionine residues significantly narrowed the available space within the substrate-binding pocket.
Improvement of an Unusual Twin-Arginine Transporter Leader Peptide by a Codon-Based Randomization Approach
Authors: Monroy-Lagos Olga , Soberon Xavier , Gaytan Paul , Osuna Joel 
Published: May 2006

ABSTRACT

Secretion of
Escherichia coli
penicillin acylase was improved by codon-based random mutagenesis of its signal peptide. The mutagenesis technology was applied to the gene region coding for positions Lys2 to Thr13 (N half) and Ala14 to Leu25 (C half) of the signal peptide. Protein secretion was higher in several signal peptide variants (up to fourfold with respect to the wild-type value).
Longitudinal Farm Study of Extended-Spectrum β-Lactamase-Mediated Resistance
Authors: Liebana E. , Batchelor M. , Hopkins K. L. , Clifton-Hadley F. A. , Teale C. J. , Foster A. , Barker L. , Threlfall E. J. , Davies R. H. 
Published: May 2006

ABSTRACT

Extended-spectrum β-lactamase (ESBL)-mediated resistance is of considerable importance in human medicine. Recently, such enzymes have been reported in bacteria from animals. We describe a longitudinal study of a dairy farm suffering calf scour with high mortality rates. In November 2004, two
Escherichia coli
isolates with resistance to a wide range of β-lactams (including amoxicillin-clavulanate and cefotaxime) were isolated from scouring calves. Testing by PCR and sequence analysis confirmed the isolates as being both
bla
CTX-M14/17
and
bla
TEM-35
(IRT-4)
positive. They had indistinguishable plasmid and pulsed-field gel electrophoresis (PFGE) profiles. Transferability studies demonstrated that
bla
CTX-M
was located on a conjugative 65-MDa IncK plasmid. Following a farm visit in December 2004, 31/48 calves and 2/60 cows were positive for
E. coli
with
bla
CTX-M
. Also, 5/48 calf and 28/60 cow samples yielded
bla
CTX
- and
bla
TEM
-negative
E. coli
isolates that were resistant to cefotaxime, and sequence analysis confirmed that these presented mutations in the promoter region of the chromosomal
ampC
gene. Fingerprinting showed 11 different PFGE types (seven in
bla
CTX-M
-positive isolates). Six different PFGE clones conjugated the same
bla
CTX-M
-positive IncK plasmid. One clone carried a different-sized,
bla
CTX-M
-positive, transformable plasmid. This is the first report of
bla
CTX-M
from livestock in the United Kingdom, and this report demonstrates the complexity of ESBL epidemiology. Results indicate that horizontal plasmid transfer between strains as well as horizontal gene transfer between plasmids have contributed to the spread of resistance. We have also shown that some clones can persist for months, suggesting that clonal spread also contributes to the perpetuation of resistance.
Emergence of
Cryptococcus gattii
in a Novel Environment Provides Clues to Its Incubation Period
Authors: MacDougall L. , Fyfe M. 
Published: May 2006

ABSTRACT

Cryptococcus gattii
emerged in 1999 in a distinct ecologic environment on Vancouver Island, Canada. Estimates of incubation period were derived from an analysis of travelers with discreet exposures to this region. Individual case incubation periods ranged from 2 to 11 months, with a median of 6 to 7 months.
Use of an Acute Seroconversion Panel To Evaluate a Third-Generation Enzyme-Linked Immunoassay for Detection of Human Immunodeficiency Virus-Specific Antibodies Relative to Multiple Other Assays
Authors: Louie Brian , Pandori Mark W. , Wong Ernest , Klausner Jeffrey D. , Liska Sally 
Published: May 2006

ABSTRACT
A human immunodeficiency virus type 1 (HIV-1)/HIV-2 antibody screening assay, the Genetic Systems HIV-1/HIV-2 PLUS O EIA, was compared to several established screening or confirmatory tests using an acute HIV seroconversion panel. The HIV-1/HIV-2 PLUS O EIA showed an improved sensitivity over all tested antibody screening methods, and detected antibody in 7 of 19 specimens found to be negative by a first-generation EIA but positive for the presence of HIV RNA.
Isolation, Characterization, and Epidemiological Assessment of Shiga Toxin-Producing
Escherichia coli
O84 Isolates from New Zealand
Authors: Cookson Adrian L. , Croucher Dawn , Pope Chris , Bennett Jenny , Thomson-Carter Fiona , Attwood Graeme T. 
Published: May 2006

ABSTRACT

Shiga toxin-producing
Escherichia coli
O84 isolates (
n
= 22) were examined using culture- and molecularly based methods in order to compare their phenotypic and genotypic characteristics. These analyses directly linked Shiga toxin-producing
Escherichia coli
O84 isolates from cattle and sheep with human isolates indicating that New Zealand livestock may be a reservoir of infection.
Hg(3P1) photosensitized decomposition of 2,5-dihydrofuran
Authors: Francis B. , Sherwood A. G. 
Published: May 2006

The mercury photosensitized decomposition of 2,5-dihydrofuran was studied in the vapor phase at 25 ± 2 °C. Major products are carbon monoxide, propene, and hydrogen, while biallyl, allene, methylacetylene, furan, 2,3-dihydrofuran, tetrahydrofuran, and small amounts of three unidentified products are also produced. The quantum yields of all products are decreased by increasing substrate pressure, indicating collisional deactivation of an excited state precursor which, at low pressures, decomposes according to the scheme [Formula: see text]The product P is not furan and its possible identity is discussed. The free radical component of the reaction was further studied by carrying out the reaction in the presence of nitric oxide. The results are consistent with the above processes.
Antisense Oligonucleotide Inhibition of Tumor Necrosis Factor Receptor 1 Protects the Liver from Radiation-Induced Apoptosis
Authors: Huang Xiao W. , Yang Jiong , Dragovic Aleksandar F. , Zhang Hong , Lawrence Theodore S. , Zhang Ming 
Published: May 2006

AbstractPurpose: Liver damage by radiation limits its efficacy in cancer treatment. As radiation can generate apoptotic signals, we wished to examine the potential to protect the liver by inhibiting apoptosis through two key mediators, FAS and tumor necrosis factor receptor 1 (TNFR1).Experimental Design: Radiation-induced liver damage was assessed by serum aspartate aminotransferase and alanine aminotransferase, hepatocyte micronucleus formation, and apoptosis assays (terminal nucleotidyl transferase–mediated nick end labeling and caspase-3 cleavage) in mice. Protection was evaluated by pretreating mice with antisense oligonucleotides (ASO) for FAS or TNFR1 prior to radiation. TNF-α production in liver and in Kupffer cells were determined by ELISA.Results: Radiation increased liver FAS and TNFR1 transcription in a dose- and time-dependent manner (maximized at 25 Gy and 8 hours postirradiation). Pretreatment with ASOs for FAS and TNFR1 resulted in the inhibition of liver FAS and TNFR1 by 78% and 59%, respectively. Inductions of serum aspartate aminotransferase and alanine aminotransferase were observed at 2 hours after radiation and could be reduced by pretreating mice with ASO for TNFR1 but not FAS or control oligonucleotide. Radiation-induced liver apoptosis (terminal nucleotidyl transferase–mediated nick end labeling staining and caspase-3 activation on Western blot) and hepatocyte micronucleus formation were reduced by pretreatment with ASO for TNFR1. In addition, radiation stimulated TNF-α production both in irradiated liver and in cultured Kupffer cells by &gt;50% and 100%, respectively.Conclusion: This study suggests that ionizing radiation activates apoptotic signaling through TNFR1 in the liver, and thus provides a rationale for anti-TNFR1 apoptotic treatment to prevent radiation-induced liver injury.
Patterns of ambulatory care utilization in Taiwan
Authors: Chen Tzeng-Ji , Chou Li-Fang , Hwang Shinn-Jang 
Published: May 2006

Abstract

Background
We used the insurance claims of a representative cohort to quantify the patterns of ambulatory care visits, especially the doctor-shopping phenomenon, in Taiwan.

Methods
The ambulatory visit files of the 200,000-person cohort datasets from the National Health Insurance Research Database in 2002 were analyzed. Only a visit with physician consultation would be considered. We computed the visit patterns both by visit count and by patient count.

Results
In 2002, there were 182,474 eligible people with 2,443,003 physician consultations. During the year, 87.4% of the cohort had visited physician clinics and 57.5% had visited hospital-based outpatient or emergency departments. On average, a person had 13.4 physician consultations and consulted 3.4 specialties, 5.2 physicians, and 3.9 healthcare facilities in a year. In 2002, 17.3% of the cohort had ever visited different healthcare facilities on the same day; 23.5% had ever visited physicians of the same specialty at different healthcare facilities within 7 days and the percentage of second visits was 3.8% of all visits. Besides, 7.6% of the cohort had visited two or more specialties at the same facility on the same day, and such visits make up 2.5% of all visits.

Conclusion
The people in Taiwan did visit the physicians and outpatient departments frequently. Many patients not only consulted several physicians of different specialties and at different healthcare facilities during the year, but also switched the physicians and facilities quickly. An effective referral system with efficient data exchange between facilities might be the solution.
Time-domain 1H NMR characterization of the liquid phase in greenwood
Authors: Labbé Nicole , De Jéso Bernard , Lartigue Jean-Claude , Daudé Gérard , Pétraud Michel , Ratier Max 
Published: May 2006

Abstract
The time domain of 1H NMR spectroscopy allows straightforward editing of the T
2 relaxation profiles in maritime pine wood. A new method from the Carr-Purcell-Meiboom-Gill sequence is proposed to measure the amount and distribution of water in wood, as well as the location of major dissolved organic materials. A general calibration model giving reliable and precise identification of these parameters is described. The method presented for editing T
2 relaxation profiles (obtained by the Contin program) may be helpful in solving practical drying and gluing problems in the wood industry. It can be used for monitoring chemical modifications of wood fibers involved in the design of wood composite materials.
Analytical tools to predict changes in properties of oriented strandboard exposed to the fungus Postia placenta
Authors: Kent Scott M. , Leichti Robert J. , Morrell Jeffrey J. , Rosowsky David V. , Kelley Stephen S. 
Published: May 2006

Abstract
Weight loss, specific gravity and strength are traditional measures of how wood changes after fungal exposure. This study investigated the effects of fungal decay on properties of oriented strand board (OSB) made of aspen including weight loss, specific gravity, dowel-bearing strength, shear strength, and alkali solubility. Shear strength and alkali solubility were strongly correlated with specific gravity. In addition, X-ray densitometry and near-infrared (NIR) spectroscopy were used to study the decay process. X-Ray densitometry was used to assess localized density around the dowel-bearing embedment zone of a nail. A statistical model using the specific gravity directly under the nail from dowel-bearing strength tests as the explanatory variable had a higher coefficient of determination than models using the gross specific gravity of the sample. Predictive models using NIR spectro-scopy, in combination with multivariate statistical methods, showed promise as predictors of weight loss, shear strength, dowel-bearing strength, and solubility.
Periodontitis and Plasma C‐Reactive Protein During Pregnancy
Authors: Pitiphat Waranuch , Joshipura Kaumudi J. , Rich‐Edwards Janet W. , Williams Paige L. , Douglass Chester W. , Gillman Matthew W. 
Published: May 2006

Background: Periodontitis has been associated with increased risk of adverse pregnancy outcomes and elevated C‐reactive protein (CRP) concentrations in non‐pregnant adults. We examined the relationship between periodontitis and CRP among women who provided dental radiographs and had blood collected during early pregnancy, excluding smokers and diabetic patients.Methods: From Project Viva, an ongoing cohort study, we measured plasma CRP in 35 subjects with periodontitis (i.e., at least one site with ≥3 mm of alveolar bone loss) and a random sample of 66 periodontally healthy subjects matched on age and race/ethnicity. We performed linear regression analysis with log‐transformed CRP levels as the outcome.Results: The mean (± SE) CRP level was 65% higher (95% confidence interval: –2%, 180%; P = 0.06) in women with periodontitis (2.46 ± 0.52 mg/l) than in controls (1.49 ± 0.22 mg/l), adjusting for factors related to CRP levels, including age, race/ethnicity, pre‐pregnancy body mass index, alcohol intake, education, income, and gestational age at blood collection.Conclusions: These findings suggest that periodontitis may increase CRP levels in pregnancy. CRP could potentially mediate the association of periodontitis with adverse pregnancy outcomes.
New 2‐hydroxyethyl methacrylate resins with good swelling characteristics
Authors: Bukowska Agnieszka , Bukowski Wiktor , Noworól Jarosław 
Published: May 2006

Abstract2‐Hydroxyethyl methacrylate copolymers with styrene and series of the cross‐linkers (divinylbenzene and mono‐, di‐ and triethylene glycol dimethacrylates) with low cross‐linking degree (2–5 mol %) were obtained by suspension polymerization. Loading capacity of the resins, their glass transition temperature, and swelling characteristics in 20 solvents were analyzed depending on monomers composition. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1487–1493, 2006
Construction and evaluation of novel fusion proteins for targeted delivery of micro particles to cellulose surfaces
Authors: Lewis William , Keshavarz‐Moore Eli , Windust John , Bushell Donna , Parry Neil 
Published: May 2006

AbstractThe use of IgG antibodies and fragments has been limited to specific sectors of the biotechnology industry due to the high cost of producing large batches of product necessary for alternative applications. A novel class of Camelid antibodies, known as VHH offer a more economical opportunity to meet a wider application in industry. In this study, we report the evaluation of four llama VHH‐cellulose binding domain fusion proteins displaying varying formats of VHH and CBD domains. Proteins were characterized in a targeted particle delivery system as a method of delivering agents such as perfume to laundry in the wash cycle. Fusion proteins were shown to be stable at high pH and in the presence of a detergent base. They were also shown to bind effectively to both the designated antigen, the azo‐dye reactive‐red 6 (either conjugated to BSA or attached to coacervate microparticles), and cellulose. Binding strength differences were observed between the different fusion protein formats using surface plasmon resonance. The effect of key laundry ingredients was also studied. Combining the fusion proteins and particles into a delivery and deposition study generated clear microscopy evidence for bifunctionality. Confirmation of this was validated by GC‐MS analysis of retained fragrance. This research, reporting the construction and characterization of a variety of fusion proteins, illustrates that the single multidomain fusion protein route offers a new technology for successful targeted delivery of encapsulated benefit agents. Furthermore, the potential to modify or select for proteins to recognize a wide range of surfaces is also possible. © 2006 Wiley Periodicals, Inc.
Stoichiometric and kinetic characterisation of Nitrobacter in mixed culture by decoupling the growth and energy generation processes
Authors: Vadivelu Vel M. , Yuan Zhiguo , Fux Christian , Keller Jurg 
Published: May 2006

AbstractThe growth, maintenance and lysis processes of Nitrobacter were characterised. A Nitrobacter culture was enriched in a sequencing batch reactor (SBR). Fluorescent in situ hybridisation showed that Nitrobacter constituted 73% of the bacterial population. Batch tests were carried out to measure the oxygen uptake rate and/or nitrite consumption rate when both nitrite and CO2 were in excess, and in the absence of either of these two substrates. The results obtained, along with the SBR performance data, allowed the determination of the maintenance coefficient and in situ cell lysis rate of Nitrobacter. Nitrobacter spends a significant amount of energy for maintenance, which varies considerably with the specific growth rate. At maximum growth, Nitrobacter consume nitrite at a rate of 0.042 mgN/mgCODbiomass · h for maintenance purposes, which increases more than threefold to 0.143 mgN/mgCODbiomass · h in the absence of growth. In the SBR, where Nitrobacter grew at 40% of its maximum growth rate, a maintenance coefficient of 0.113 mgN/mgCOD · h was found, resulting in 42% of the total amount of nitrite being consumed for maintenance. The above three maintenance coefficient values obtained at different growth rates appear to support the maintenance model proposed in Pirt (1982). The in situ lysis rate of Nitrobacter was determined to be 0.07/day under aerobic conditions at 22°C and pH 7.3. Further, the maximum specific growth rate of Nitrobacter was estimated to be 0.02/h (0.48/day). The affinity constant of Nitrobacter with respect to nitrite was determined to be 1.50 mgNO‐N/L, independent of the presence or absence of CO2. © 2006 Wiley Periodicals, Inc.
Elevated vascular endothelial cell growth factor affects mesocardial morphogenesis and inhibits normal heart bending
Authors: Drake Christopher J. , Wessels Andy , Trusk Tom , Little Charles D. 
Published: May 2006

AbstractMontage of repeated images of QH‐1 labeled quail hearts at 8 and 12 somite stages. Color has been inverted using Photoshop for design purposes. See Drake et al., Developmental Dynamics 235:10–18. © 2006 Wiley‐Liss, Inc.