bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of P Availability on Temporal Dynamics of Carbon Allocation and
Glomus intraradices
High-Affinity P Transporter Gene Induction in Arbuscular Mycorrhiza
Authors: Olsson Pål Axel , Hansson Maria C. , Burleigh Stephen H.
Published: June 2006

Arbuscular mycorrhizal (AM) fungi depend on a C supply from the plant host and simultaneously provide phosphorus to the colonized plant. We therefore evaluated the influence of external P on C allocation in monoxenic
Daucus carota
-
Glomus intraradices
cultures in an AM symbiosis. Fungal hyphae proliferated from a solid minimal medium containing colonized roots into a C-free liquid minimal medium with high or low P availability. Roots and hyphae were harvested periodically, and the flow of C from roots to fungus was measured by isotope labeling. We also measured induction of a
G. intraradices
high-affinity P transporter to estimate fungal P demand. The prevailing hypothesis is that high P availability reduces mycorrhizal fungal growth, but we found that C flow to the fungus was initially highest at the high P level. Only at later harvests, after 100 days of in vitro culture, were C flow and fungal growth limited at high P availability. Thus, AM fungi can benefit initially from P-enriched environments in terms of plant C allocation. As expected, the P transporter induction was significantly greater at low P availability and greatest in very young mycelia. We found no direct link between C flow to the fungus and the P transporter transcription level, which indicates that a good C supply is not essential for induction of the high-affinity P transporter. We describe a mechanism by which P regulates symbiotic C allocation, and we discuss how this mechanism may have evolved in a competitive environment.
Microbial Diversity in Maras Salterns, a Hypersaline Environment in the Peruvian Andes
Authors: Maturrano Lenin , Santos Fernando , Rosselló-Mora Ramon , Antón Josefa
Published: June 2006

Maras salterns are located 3,380 m above sea level in the Peruvian Andes. These salterns consist of more than 3,000 little ponds which are not interconnected and act as crystallizers where salt precipitates. These ponds are fed by hypersaline spring water rich in sodium and chloride. The microbiota inhabiting these salterns was examined by fluorescence in situ hybridization (FISH), 16S rRNA gene clone library analysis, and cultivation techniques. The total counts per milliliter in the ponds were around 2 × 106to 3 × 106cells/ml, while the spring water contained less than 100 cells/ml and did not yield any detectable FISH signal. The microbiota inhabiting the ponds was dominated (80 to 86% of the total counts) byArchaea, whileBacteriaaccounted for 10 to 13% of the 4′,6′-diamidino-2-phenylindole (DAPI) counts. A total of 239 16S rRNA gene clones were analyzed (132Archaeaclones and 107Bacteriaclones). According to the clone libraries, the archaeal assemblage was dominated by microorganisms related to the cosmopolitan square archaeon “Haloquadra walsbyi,” although a substantial number of the sequences in the libraries (31% of the 16S rRNA gene archaeal clones) were related toHalobacteriumsp., which is not normally found in clone libraries from solar salterns. All the bacterial clones were closely related to each other and to the γ-proteobacterium “Pseudomonas halophila” DSM 3050. FISH analysis with a probe specific for this bacterial assemblage revealed that it accounted for 69 to 76% of the total bacterial counts detected with aBacteria-specific probe. When pond water was used to inoculate solid media containing 25% total salts, both extremely halophilicArchaeaandBacteriawere isolated. Archaeal isolates were not related to the isolates in clone libraries, although several bacterial isolates were very closely related to the “P. halophila” cluster found in the libraries. As observed for other hypersaline environments, extremely halophilic bacteria that had ecological relevance seemed to be easier to culture than their archaeal counterparts.
Field Trial Evaluating the Influence of Prophylactic and Therapeutic Antimicrobial Administration on Antimicrobial Resistance of Fecal
Escherichia coli
in Dairy Calves
Authors: Berge Anna Catharina B. , Moore Dale A. , Sischo William M.
Published: June 2006

The objective of this study was to describe the influence of in-feed and therapeutic antimicrobials on resistance in commensal fecal
Escherichia coli
isolated from preweaned calves. Four groups of 30, day-old calf-ranch calves were enrolled and raised until 4 weeks of age. Groups 1 to 3 were raised without antimicrobials in the feed. Group 1 was isolated from the other groups and received no antimicrobial therapy. Group 2 was housed on the calf ranch and did not receive antimicrobial therapy, whereas groups 3 and 4 could be treated with antimicrobials. Group 4 was fed neomycin and tetracycline HCl in the milk replacer. Fecal samples were collected from calves on days 1, 14, and 28. Three
E. coli
isolates per sample were evaluated for susceptibility to 12 antimicrobials. Cluster analysis was used to group isolates having similar susceptibility patterns. Cumulative logistic regression was used to evaluate factors associated with increasing levels of multiple antimicrobial resistance. In-feed antimicrobials were associated with higher levels of multiple antimicrobial resistance in fecal
E. coli
.f In calves not receiving in-feed antimicrobials, older calves had higher levels of resistance compared to day-old calves. Individual antimicrobial therapy increased resistance in these calves but appeared to be transient. There was no environmental influence on resistance in
E. coli
populations among study groups.
Rapid One-Step Quantitative Reverse Transcriptase PCR Assay with Competitive Internal Positive Control for Detection of Enteroviruses in Environmental Samples
Authors: Gregory Jason B. , Litaker R. Wayne , Noble Rachel T.
Published: June 2006

Human enteroviruses can serve as a more accurate indicator of human fecal contamination than conventional bacteriological fecal indicators. We describe here a quantitative reverse transcriptase PCR (qRT-PCR) assay specifically tailored to detect these viruses in environmental waters. The assay included a competitive internal positive control (CIPC) that allowed the inhibition of qRT-PCRs to be quantitatively assessed. Coamplification of the CIPC with enteroviral genetic material did not affect the sensitivity, specificity, or reproducibility of the enteroviral qRT-PCR assay. The assay is rapid (less than 5 h from sample to result), has a wide dynamic range (>3 logs), and is capable of detecting as few as 25 enteroviral genomes with an average amplification efficiency of 0.91. In samples with low or moderate inhibition, the delay in CIPC amplification was used to adjust enterovirus qRT-PCR concentrations to account for losses due to inhibition. Samples exhibiting significant inhibition were not corrected but instead diluted twofold and immediately assayed again. Using significantly inhibited samples, it was found that dilution relieved inhibition in 93% (25 of 27) of the samples. In addition, 15% (4 of 27) of these previously negative samples contained enteroviral genomes. The high-throughput format of the assay compared to conventional culture-based methods offers a fast, reliable, and specific method for detecting enteroviruses in environmental water samples. The ability of the assay to identify false negatives and provide improved quantitative assessments of enterovirus concentrations will facilitate the tracking of human fecal contamination and the assessment of potential public health risk due to enteroviruses in recreational and shellfish harvesting waters.
Biodiversity and Classification of Lactococcal Phages
Authors: Deveau Hélène , Labrie Simon J. , Chopin Marie-Christine , Moineau Sylvain
Published: June 2006

For this study, an in-depth review of the classification ofLactococcus lactisphages was performed. Reference phages as well as unclassified phages from international collections were analyzed by stringent DNA-DNA hybridization studies, electron microscopy observations, and sequence analyses. A new classification scheme for lactococcal phages is proposed that reduces the current 12 groups to 8. However, two new phages (Q54 and 1706), which are unrelated to known lactococcal phages, may belong to new emerging groups. The multiplex PCR method currently used for the rapid identification of phages from the three main lactococcal groups (936, c2, and P335) was improved and tested against the other groups, none of which gave a PCR product, confirming the specificity of this detection tool. However, this method does not detect all members of the highly diverse P335 group. The lactococcal phages characterized here were deposited in the Félix d'Hérelle Reference Center for Bacterial Viruses and represent a highly diverse viral community from the dairy environment.
Heterologous Expression of
Arabidopsis
UDP-Glucosyltransferases in
Saccharomyces cerevisiae
for Production of Zearalenone-4-
O
-Glucoside
Authors: Poppenberger Brigitte , Berthiller Franz , Bachmann Herwig , Lucyshyn Doris , Peterbauer Clemens , Mitterbauer Rudolf , Schuhmacher Rainer , Krska Rudolf , Glössl Josef , Adam Gerhard
Published: June 2006

Zearalenone, a secondary metabolite produced by several plant-pathogenic fungi of the genus
Fusarium
, has high estrogenic activity in vertebrates. We developed a
Saccharomyces cerevisiae
bioassay strain that we used to identify plant genes encoding UDP-glucosyltransferases that can convert zearalenone into zearalenone-4-
O
-glucoside (ZON-4-
O
-Glc). Attachment of the glucose moiety to zearalenone prevented the interaction of the mycotoxin with the human estrogen receptor. We found that two of six clustered, similar
UGT73C
genes of
Arabidopsis thaliana
encode glucosyltransferases that can inactivate zearalenone in the yeast bioassay. The formation of glucose conjugates seems to be an important plant mechanism for coping with zearalenone but may result in significant amounts of “masked” zearalenone in
Fusarium
-infected plant products. Due to the unavailability of an analytical standard, the ZON-4-
O
-Glc is not measured in routine analytical procedures, even though it can be converted back to active zearalenone in the digestive tracts of animals. Zearalenone added to yeast transformed with UGT73C6 was converted rapidly and efficiently to ZON-4-
O
-Glc, suggesting that the cloned UDP-glucosyltransferase could be used to produce reference glucosides of zearalenone and its derivatives.
Stability and Performance of
Xanthobacter autotrophicus
GJ10 during 1,2-Dichloroethane Biodegradation
Authors: Baptista Ines I. R. , Peeva Ludmila G. , Zhou Ning-Yi , Leak David J. , Mantalaris Athanasios , Livingston Andrew G.
Published: June 2006

A nucleic acid-based approach was used to investigate the dynamics of a microbial community dominated by
Xanthobacter autotrophicus
GJ10 in the degradation of synthetic wastewater containing 1,2-dichloroethane (DCE). This study was performed over a 140-day period in a nonsterile continuous stirred-tank bioreactor (CSTB) subjected to different operational regimens: nutrient-limiting conditions, baseline operation, and the introduction of glucose as a cosubstrate. The microbial community was analyzed by a combination of fluorescence in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE). Under nutrient-limiting conditions, DCE degradation was restricted, but this did not affect the dominance of strain GJ10, determined by FISH to comprise 85% of the active population. During baseline operation, DCE degradation improved significantly to over 99.5% and then remained constant throughout the subsequent experimental period. DGGE profiles revealed a stable, complex community, while FISH indicated that strain GJ10 remained the dominant species. During the addition of glucose as a cosubstrate, DGGE profiles showed a proliferation of other species in the CSTB. The percentage of strain GJ10 dropped to 8% of the active population in just 5 days, although this did not affect the DCE biodegradation performance. The return to baseline conditions was accompanied by the reestablishment of strain GJ10 as the dominant species, suggesting that this system responds robustly to external perturbations, both at the functional biodegradation level and at the individual strain level.
A Cold-Sensitive
Listeria monocytogenes
Mutant Has a Transposon Insertion in a Gene Encoding a Putative Membrane Protein and Shows Altered (p)ppGpp Levels
Authors: Liu Siqing , Bayles Darrell O. , Mason Tricia M. , Wilkinson Brian J.
Published: June 2006

A cold-sensitive
Listeria monocytogenes
mutant designated cld-14 was obtained by transposon Tn
917
mutagenesis. The gene interrupted by Tn
917
in cld-14 was the
L. monocytogenes
LMOf2365_
1485
homolog, which exhibits 45.7% homology to the
Bacillus subtilis yqfF
locus. LMOf2365_
1485
, here designated
pgpH
, encodes a putative integral membrane protein with a predicted molecular mass of 81 kDa. PgpH is predicted to contain a conserved N-terminal signal peptide sequence, seven transmembrane helices, and a hydrophilic C terminus, which likely extends into the cytosol. The Tn
917
insertion in
pgpH
is predicted to result in production of a premature polypeptide truncated at the fifth transmembrane domain. The C terminus of PgpH, which is probably absent in cld-14, contains a highly conserved HD domain that belongs to a metal-dependent phosphohydrolase family. Strain cld-14 accumulated higher levels of (p)ppGpp than the wild type accumulated, indicating that the function of PgpH may be to adjust cellular (p)ppGpp levels during low-temperature growth. The cld-14
pgpH

+

complemented strain was able to grow at a low temperature, like the parent strain, providing direct evidence that the activity of PgpH is important in low-temperature adaptation. Because of its predicted membrane location, PgpH may play a critical role in sensing the environmental temperature and altering cellular (p)ppGpp levels to allow the organism to adapt to low temperatures.
Development, Evaluation, and Standardization of a Real-Time TaqMan Reverse Transcription-PCR Assay for Quantification of Hepatitis A Virus in Clinical and Shellfish Samples
Authors: Costafreda M. Isabel , Bosch Albert , Pintó Rosa M.
Published: June 2006

A standardized real-time reverse transcription-PCR (RT-PCR) assay has been developed for an accurate estimation of the number of genome copies of hepatitis A virus (HAV) in clinical and shellfish samples. Real-time procedures were based on the amplification of a fragment of the highly conserved 5′ noncoding region and detection through an internal fluorescent probe, including TaqMan and beacon chemistries, in one- and two-step RT-PCR formats. The best performance in terms of sensitivity and reproducibility was achieved by a one-step TaqMan RT-PCR, with a sensitivity enabling the detection of 0.05 infectious unit and 10 copies of a single-stranded RNA (ssRNA) synthetic transcript. Standard reagents, such as a mengovirus strain and an ssRNA transcript, were employed as controls of nucleic acid extraction and RT-PCR, respectively. The test proved to be highly specific after a broad panel of enteric viruses was tested. Sequence alignment of target regions of the primers and probe proved them to be adequate for the quantification of all HAV genotypes. In addition, a quasispecies analysis of the mutant spectrum indicated that these regions are not prone to variability, thus confirming their robustness.
Evaluation of Two Methods of Determining the Efficacies of Two Alcohol-Based Hand Rubs for Surgical Hand Antisepsis
Authors: Kampf Günter , Ostermeyer Christiane , Heeg Peter , Paulson Daryl
Published: June 2006

The antimicrobial efficacies of preparations for surgical hand antisepsis can be determined according to a European standard (prEN 12791 [EN]) and a U.S. standard (tentative final monograph for health care antiseptic drug products [TFM]). The U.S. method differs in the product application mode (hands and lower forearms, versus hands only in EN), the number of applications (11 over 5 days, versus a single application in EN), the sampling times (0, 3, and 6 h after application, versus 0 and 3 h in EN), the sampling methods (glove juice versus fingertip sampling in EN), and the outcome requirements (absolute bacterial reduction factor [RF], versus noninferiority to reference treatment in EN). We have studied the efficacies of two hand rubs according to both methods. One hand rub was based on 80% ethanol and applied for 2 min, and the other one was based on 45% propan-2-ol, 30% propan-1-ol, and 0.2% mecetronium etilsulfate and applied for 1.5 min. The ethanol-based hand rub was equally effective as the 3-min reference disinfection of prEN 12791 in both the immediate (RFs, 2.97 ± 0.89 versus 2.92 ± 1.03, respectively) and sustained (RFs, 2.20 ± 1.07 versus 2.47 ± 1.25, respectively) effects. According to TFM, the immediate effects were 2.99 log
10
(day 1), 3.00 log
10
(day 2), and 3.43 log
10
(day 5), and bacterial counts were still below baseline after 6 h. The propanol-based hand rub was even more effective than the reference disinfection of prEN 12791 in both the immediate (RFs, 2.35 ± 0.99 versus 1.86 ± 0.87, respectively) and sustained (RFs, 2.17 ± 1.00 versus 1.50 ± 1.26, respectively) effects. According to TFM, the immediate effects were 2.82 log
10
(day 1), 3.29 log
10
(day 2), and 3.25 log
10
(day 5), and bacterial counts were still below baseline after 6 h. Some formulations have been reported to meet the efficacy requirements of one of the methods but not those of the other. That is why we conclude that, despite our results, meeting the efficacy requirements of one test method does not allow the claim that the requirements of the other test method are also met.
Development of Goose- and Duck-Specific DNA Markers To Determine Sources of
Escherichia coli
in Waterways
Authors: Hamilton Matthew J. , Yan Tao , Sadowsky Michael J.
Published: June 2006

The contamination of waterways with fecal material is a persistent threat to public health. Identification of the sources of fecal contamination is a vital component for abatement strategies and for determination of total maximum daily loads. While phenotypic and genotypic techniques have been used to determine potential sources of fecal bacteria in surface waters, most methods require construction of large known-source libraries, and they often fail to adequately differentiate among environmental isolates originating from different animal sources. In this study, we used pooled genomic tester and driver DNAs in suppression subtractive hybridizations to enrich for host source-specific DNA markers for
Escherichia coli
originating from locally isolated geese. Seven markers were identified. When used as probes in colony hybridization studies, the combined marker DNAs identified 76% of the goose isolates tested and cross-hybridized, on average, with 5% of the human
E. coli
strains and with less than 10% of the strains obtained from other animal hosts. In addition, the combined probes identified 73% of the duck isolates examined, suggesting that they may be useful for determining the contribution of waterfowl to fecal contamination. However, the hybridization probes reacted mainly with
E. coli
isolates obtained from geese in the upper midwestern United States, indicating that there is regional specificity of the markers identified. Coupled with high-throughput, automated macro- and microarray screening, these markers may provide a quantitative, cost-effective, and accurate library-independent method for determining the sources of genetically diverse
E. coli
strains for use in source-tracking studies. However, future efforts to generate DNA markers specific for
E. coli
must include isolates obtained from geographically diverse animal hosts.
A Constitutively Expressed, Truncated
umuDC
Operon Regulates the
recA
-Dependent DNA Damage Induction of a Gene in
Acinetobacter baylyi
Strain ADP1
Authors: Hare Janelle M. , Perkins Sara N. , Gregg-Jolly Leslie A.
Published: June 2006

In response to environmentally caused DNA damage, SOS genes are up-regulated due to RecA-mediated relief of LexA repression. In
Escherichia coli
, the SOS
umuDC
operon is required for DNA damage checkpoint functions and for replicating damaged DNA in the error-prone process called SOS mutagenesis. In the model soil bacterium
Acinetobacter baylyi
strain ADP1, however, the content, regulation, and function of the
umuDC
operon are unusual. The
umuC
gene is incomplete, and a remnant of an ISEhe3-like transposase has replaced the middle 57% of the
umuC
coding region. The
umuD
open reading frame is intact, but it is 1.5 times the size of other
umuD
genes and has an extra 5′ region that lacks homology to known
umuD
genes. Analysis of a
umuD
::
lacZ
fusion showed that
umuD
was expressed at very high levels in both the absence and presence of mitomycin C and that this expression was not affected in a
recA
-deficient background. The
umuD
mutation did not affect the growth rate or survival after UV-induced DNA damage. However, the UmuD-like protein found in ADP1 (UmuDAb) was required for induction of an adjacent DNA damage-inducible gene,
ddrR
. The
umuD
mutation specifically reduced the DNA damage induction of the RecA-dependent DNA damage-inducible
ddrR
locus by 83% (from 12.9-fold to 2.3-fold induction), but it did not affect the 33.9-fold induction of
benA
, an unrelated benzoate degradation gene. These data suggest that the response of the ADP1
umuDC
operon to DNA damage is unusual and that UmuDAb specifically regulates the expression of at least one DNA damage-inducible gene.
Temporal Prevalence of Antimicrobial Resistance in
Campylobacter
spp. from Beef Cattle in Alberta Feedlots
Authors: Inglis G. D. , Morck D. W. , McAllister T. A. , Entz T. , Olson M. E. , Yanke L. J. , Read R. R.
Published: June 2006

Antimicrobial resistance (AMR) was temporally assessed in campylobacters isolated from beef cattle (7,738 fecal samples from 2,622 animals) in four commercial feedlots in Alberta. All calves were administered chlortetracycline and oxytetracycline in feed, and a majority of the animals (93%) were injected with long-acting oxytetracycline upon arrival at the feedlot. Fecal samples from individual animals were collected upon arrival (i.e., entry sample), 69 days (standard deviation [SD] = 3 days) after arrival (i.e., interim sample), and 189 days (SD = 33 days) after arrival (i.e., exit sample) at the feedlot. In total, 1,586
Campylobacter
isolates consisting of
Campylobacter coli
(
n
= 154),
Campylobacter fetus
(
n
= 994),
Campylobacter jejuni
(
n
= 431),
Campylobacter hyointestinalis
(
n
= 4), and
Campylobacter lanienae
(
n
= 3) were recovered and characterized. The administration of antimicrobials did not decrease carriage rates of campylobacters, and minimal resistance (≤4%) to azithromycin, ciprofloxacin, enrofloxacin, gentamicin, and meropenem was observed. In contrast, substantive increases in the prevalence of isolates resistant to tetracycline and doxycycline (56 to 89%) for
C. coli
,
C. fetus
, and
C. jejuni
, as well as in the number of animals (7 to 42%) from which resistant isolates were recovered, were observed during the feedlot period. Increased resistance to erythromycin (total isolates and carriages rates) was also observed in isolates of
C. coli
over the three isolation times. The majority of
C. fetus
isolates recovered were resistant to nalidixic acid, but this was independent of when they were isolated. A relatively limited number of multidrug-resistant isolates were recovered and consisted primarily of
C. coli
resistant to tetracyclines and erythromycin (10% of isolates). Over the course of the feedlot period, considerable increases in antimicrobial resistance were observed in
C. coli
,
C. fetus
, and
C. jejuni
, but with the exception of erythromycin resistance in
C. coli
, the administration of antimicrobial agents to beef cattle was found to have a minimal impact on resistance to macrolides and fluoroquinolones, the two classes of antimicrobials used to treat campylobacteriosis in humans. However, the widespread use of antimicrobial agents in beef production and the possible horizontal transfer of mobile genetic elements with antimicrobial resistance determinants among
Campylobacter
and other bacterial taxa emphasize the need to monitor AMR development in bacteria from beef cattle.
Comparison of Mechanisms of Alkane Metabolism under Sulfate-Reducing Conditions among Two Bacterial Isolates and a Bacterial Consortium
Authors: Callaghan Amy V. , Gieg Lisa M. , Kropp Kevin G. , Suflita Joseph M. , Young Lily Y.
Published: June 2006

Recent studies have demonstrated that fumarate addition and carboxylation are two possible mechanisms of anaerobic alkane degradation. In the present study, we surveyed metabolites formed during growth on hexadecane by the sulfate-reducing isolates AK-01 and Hxd3 and by a mixed sulfate-reducing consortium. The cultures were incubated with either protonated or fully deuterated hexadecane; the sulfate-reducing consortium was also incubated with [1,2-
13
C
2
]hexadecane. All cultures were extracted, silylated, and analyzed by gas chromatography-mass spectrometry. We detected a suite of metabolites that support a fumarate addition mechanism for hexadecane degradation by AK-01, including methylpentadecylsuccinic acid, 4-methyloctadecanoic acid, 4-methyloctadec-2,3-enoic acid, 2-methylhexadecanoic acid, and tetradecanoic acid. By using
d
34
-hexadecane, mass spectral evidence strongly supporting a carbon skeleton rearrangement of the first intermediate, methylpentadecylsuccinic acid, was demonstrated for AK-01. Evidence indicating hexadecane carboxylation was not found in AK-01 extracts but was observed in Hxd3 extracts. In the mixed sulfate-reducing culture, however, metabolites consistent with both fumarate addition and carboxylation mechanisms of hexadecane degradation were detected, which demonstrates that multiple alkane degradation pathways can occur simultaneously within distinct anaerobic communities. Collectively, these findings underscore that fumarate addition and carboxylation are important alkane degradation mechanisms that may be widespread among phylogenetically and/or physiologically distinct microorganisms.
Energetics and Surface Properties of
Pseudomonas putida
DOT-T1E in a Two-Phase Fermentation System with 1-Decanol as Second Phase
Authors: Neumann Grit , Cornelissen Sjef , van Breukelen Frank , Hunger Steffi , Lippold Holger , Loffhagen Norbert , Wick Lukas Y. , Heipieper Hermann J.
Published: June 2006

The solvent-tolerant strain
Pseudomonas putida
DOT-T1E was grown in batch fermentations in a 5-liter bioreactor in the presence and absence of 10% (vol/vol) of the organic solvent 1-decanol. The growth behavior and cellular energetics, such as the cellular ATP content and the energy charge, as well as the cell surface hydrophobicity and charge, were measured in cells growing in the presence and absence of 1-decanol. Although the cells growing in the presence of 1-decanol showed an about 10% reduced growth rate and a 48% reduced growth yield, no significant differences were measured either in the ATP and potassium contents or in the energy charge, indicating that the cells adapted completely at the levels of membrane permeability and energetics. Although the bacteria needed additional energy for adaptation to the presence of the solvent, they were able to maintain or activate electron transport phosphorylation, allowing homeostasis of the ATP level and energy charge in the presence of the solvent, at the price of a reduced growth yield. On the other hand, significantly enhanced cell hydrophobicities and more negative cell surface charges were observed in cells grown in the presence of 1-decanol. Both reactions occurred within about 10 min after the addition of the solvent and were significantly different after killing of the cells with toxic concentrations of HgCl
2
. This adaptation of the surface properties of the bacterium to the presence of solvents seems to be very similar to previously observed reactions on the level of lipopolysaccharides, with which bacteria adapt to environmental stresses, such as heat shock, antibiotics, or low oxygen content. The results give clear physiological indications that the process with
P. putida
DOT-T1E as the biocatalyst and 1-decanol as the solvent is a stable system for two-phase biotransformations that will allow the production of fine chemicals in economically sound amounts.
Inmate-made weapons in prison facilities: assessing the injury risk
Authors: Lincoln J M , Chen L-H , Mair J S , Biermann P J , Baker S P
Published: June 2006

More than 2400 correctional workers in the United States required medical attention in 1999 following assaults by inmates, often with unconventional “homemade” weapons. Little information is available about these weapons. The authors surveyed 101 state prisons for a 12 month period within 2002–03, and 70 responded. A total of 1326 weapons were either confiscated (1086) or used to injure inmates (203) or staff (37). Staff were most often attacked with clubs. The prison store was the most common source of materials used to make confiscated weapons. Issued items were the most common source of materials used to make weapons to injure staff. The injury rate for staff was 1.0/1000 workers per year. The annual cost of injuries for time lost and medical care for staff was estimated at $1,125,000 in these 70 prisons. Results identify materials that should be redesigned to prevent modifications to make weapons. Prison stores and issued items deserve special attention.
Patterns of road traffic injuries in a vulnerable population in Hyderabad, India
Authors: Dandona R , Kumar G A , Raj T S , Dandona L
Published: June 2006

Objective:To describe patterns of road traffic injuries (RTI) in a vulnerable population—pedestrians and users of motorized two-wheeled vehicles (MTVs)—in Hyderabad, India.

Methods:4019 pedestrians and 4183 MTV drivers provided information on the most recent road traffic crash (RTC) irrespective of the level of injury in the last one year for 17 454 and 17 242 household members, respectively. Crashes in which any household member was involved as a pedestrian or MTV user were analysed.

Results:Involvement in an RTC as a pedestrian or MTV user was reported for 1513 (4.4%, 95% CI 4.2 to 4.6%) people in the last one year. In these crashes, the person involved was an MTV user in 1264 (83.5%), aged 21–40 years in 973 (64.3%), and male in 1202 (79.4%). Six (0.4%) people died in RTCs and the cause was collision with a vehicle/person in 1133 (75%) crashes. Among the 1306 people who were injured and survived, 174 (13.3%) were treated as inpatients, 38 (2.9%) could not return fully to routine daily activities, 630 (48.2%) took leave from their regular occupation, and 13 (1%) lost their jobs following injury. Using a three month recall period, the annual incidence per 100 000 population of RTC as a pedestrian or MTV user was 2288 and of non-fatal RTI was 1931, and that of fatal RTI using one year recall period was 17.3 in this population.

Conclusions:These findings on how RTI are caused, their type, and outcomes in pedestrians and MTV users can assist in identifying interventions to improve road safety for this vulnerable population in India, and can also be useful for monitoring the effectiveness of such interventions.
The association between changes in household firearm ownership and rates of suicide in the United States, 1981–2002
Authors: Miller M , Azrael D , Hepburn L , Hemenway D , Lippmann S J
Published: June 2006

Objective:To explore whether recent declines in household firearm prevalence in the United States were associated with changes in rates of suicide for men, women, and children.

Methods:This time series study compares changes in suicide rates to changes in household firearm prevalence, 1981–2002. Multivariate analyses adjust for age, unemployment, per capita alcohol consumption, and poverty. Regional fixed effects controlled for cross sectional, time invariant differences among the four census regions. Standard errors of parameter estimates are adjusted to account for serial autocorrelation of observations over time.

Results:Over the 22 year study period household firearm ownership rates declined across all four regions. In multivariate analyses, each 10% decline in household firearm ownership was associated with significant declines in rates of firearm suicide, 4.2% (95% CI 2.3% to 6.1%) and overall suicide, 2.5% (95% CI 1.4% to 3.6%). Changes in non-firearm suicide were not associated with changes in firearm ownership. The magnitude of the association between changes in household firearm ownership and changes in rates of firearm and overall suicide was greatest for children: for each 10% decline in the percentage of households with firearms and children, the rate of firearm suicide among children 0–19 years of age dropped 8.3% (95% CI 6.1% to 10.5%) and the rate of overall suicide dropped 4.1% (2.3% to 5.9%).

Conclusion:Changes in household firearm ownership over time are associated with significant changes in rates of suicide for men, women, and children. These findings suggest that reducing availability to firearms in the home may save lives, especially among youth.
The theory of community based health and safety programs: a critical examination: Figure 1
Authors: Nilsen P
Published: June 2006

This paper examines the theoretical underpinning of the community based approach to health and safety programs. Drawing upon the literature, a theory is constructed by elucidating assumptions of community based programs. The theory is then put to test by analyzing the extent to which the assumptions are supported by empirical evidence and the extent to which the assumptions have been applied in community based injury prevention practice. Seven principles representing key assumptions of the community based approach to health and safety programs are identified. The analysis suggests that some of the principles may have important shortcomings. Programs overwhelmingly define geographical or geopolitical units as communities, which is problematic considering that these entities can be heterogeneous and characterized by a weak sense of community. This may yield insufficient community mobilization and inadequate program reach. At the same time, none of the principles identified as most plausible appears to be widely or fully applied in program practice. The implication is that many community based health and safety programs do not function at an optimum level, which could explain some of the difficulties in demonstrating effectiveness seen with many of these programs.
Inequalities in hospital admission rates for unintentional poisoning in young children
Authors: Groom L , Kendrick D , Coupland C , Patel B , Hippisley-Cox J
Published: June 2006

Objective:To determine the relationship between deprivation and hospital admission rates for unintentional poisoning, by poisoning agent in children aged 0–4 years.

Design:Cross sectional study of routinely collected hospital admissions data.

Setting:East Midlands, UK.

Participants:1469 admissions due to unintentional poisoning over two years.

Main outcome measure:Hospital admission rates for unintentional poisoning. Incidence rate ratios (IRRs) comparing hospital admission rates for poisoning in the most and least deprived electoral wards.

Results:Children in the most deprived wards had admission rates for medicinal poisoning that were 2–3 times higher than those in the least deprived wards (IRR 2.49, 95% CI 1.87 to 3.30). Admission rates for non-medicinal poisoning were about twice as high in the most compared to the least deprived wards (IRR 1.77, 95% CI 1.19 to 2.64). Deprivation gradients were particularly steep for benzodiazepines (IRR 5.63, 95% CI 1.72 to 18.40), antidepressants (IRR 4.58, 95% CI 1.80 to 11.66), cough and cold remedies (IRR 3.93, 95% CI 1.67 to 9.24), and organic solvents (IRR 3.69, 95% CI 1.83 to 7.44).

Conclusions:There are steep deprivation gradients for admissions to hospital for childhood poisoning, with particularly steep gradients for some psychotropic medicines. Interventions to reduce these inequalities should be directed towards areas of greater deprivation.
MONTE CARLO STUDY OF GLUEBALL MASSES IN THE HAMILTONIAN LIMIT OF SU(3) LATTICE GAUGE THEORY
Authors: LOAN MUSHTAQ , LUO XIANG-QIAN , LUO ZHI-HUAN
Published: June 2006

Using Standard Euclidean Monte Carlo techniques, we discuss in detail the extraction of the glueball masses of four-dimensional SU(3) lattice gauge theory in the Hamiltonian limit, where the temporal lattice spacing is zero. By taking into account the renormalization of both the anisotropy and the Euclidean coupling, we calculate the string tension and masses of the scalar, axial vector and tensor states using standard Wilson action on increasingly anisotropic lattices, and make an extrapolation to the Hamiltonian limit. The results are compared with estimates from various other Hamiltonian and Euclidean studies. We find that more accurate determination of the glueball masses and the mass ratios has been achieved in the Hamiltonian limit and the results are a significant improvement upon previous Hamiltonian estimates. The continuum predictions are then found by extrapolation of results obtained from smallest values of spatial lattice spacing. For the lightest scalar, tensor and axial vector states we obtain masses of m0++ = 1654±83 MeV , m2++ = 2272±115 MeV and m1+- = 2940±165 MeV , respectively. These are consistent with the estimates obtained in the previous studies in the Euclidean limit. The consistency is a clear evidence of universality between Euclidean and Hamiltonian formulations. From the accuracy of our estimates, we conclude that the standard Euclidean Monte Carlo method is a reliable technique for obtaining results in the Hamiltonian version of the theory, just as in Euclidean case.
MSSM HIGGS PHYSICS AT HIGHER ORDERS
Authors: HEINEMEYER S.
Published: June 2006

Various aspects of the Higgs boson phenomenology of the Minimal Supersymmetric Standard Model (MSSM) are reviewed. Emphasis is put on the effects of higher-order corrections. The masses and couplings are discussed in the MSSM with real and complex parameters. Higher-order corrections to Higgs boson production channels at a prospective e+e-linear collider are investigated. Corrections to Higgs boson decays to SM fermions and their phenomenological implications for hadron and lepton colliders are explored.
REFLEXIVE NUMBERS AND BERGER GRAPHS FROM CALABI–YAU SPACES
Authors: LIPATOV L. N. , SABIO VERA A. , VELIZHANIN V. N. , VOLKOV G. G.
Published: June 2006

We review the Batyrev approach to Calabi–Yau spaces based on reflexive weight vectors. The Universal CY algebra gives a possibility to construct the corresponding reflexive numbers in a recursive way. A physical interpretation of the Batyrev expression for the Calabi–Yau manifolds is presented. Important classes of these manifolds are related to the simple-laced and quasi-simple-laced numbers. We discuss the classification and recurrence relations for them in the framework of quantum field theory methods. A relation between the reflexive numbers and the so-called Berger graphs is studied. In this correspondence the role played by the generalized Coxeter labels is highlighted. Sets of positive roots are investigated in order to connect them to possible new algebraic structures stemming from the Berger matrices.
ENERGY DISTRIBUTION OF THE EINSTEIN–KLEIN–GORDON SYSTEM FOR A STATIC SPHERICALLY SYMMETRIC SPACE–TIME IN (2+1) DIMENSIONS
Authors: RADINSCHI I. , GRAMMENOS TH.
Published: June 2006

We use Møller's energy–momentum complex in order to explicitly compute the energy and momentum density distributions for an exact solution of Einstein's field equations with a negative cosmological constant, minimally coupled to a static massless scalar field in a static, spherically symmetric background in (2+1) dimensions.
Impaired intestinal and renal glucose transport in PDK-1 hypomorphic mice
Authors: Artunc Ferruh , Rexhepaj Rexhep , Völkl Harald , Grahammer Florian , Remy Christine , Sandulache Diana , Nasir Omaima , Wagner Carsten A. , Alessi Dario R. , Lang Florian
Published: June 2006

The phosphoinositide-dependent kinase-1 (PDK-1) activates the serum- and glucocorticoid-inducible kinase and protein kinase B isoforms, which, in turn, are known to stimulate the renal and intestinal Na+-dependent glucose transporter 1. The present study has been performed to explore the role of PDK-1 in electrogenic glucose transport in small intestine and proximal renal tubules. To this end, mice expressing ∼20% of PDK-1 ( pdk1hm) were compared with their wild-type littermates ( pdk1wt). According to Ussing chamber experiments, electrogenic glucose transport was significantly smaller in the jejunum of pdk1hmthan of pdk1wtmice. Similarly, proximal tubular electrogenic glucose transport in isolated, perfused renal tubule segments was decreased in pdk1hmcompared with pdk1wtmice. Intraperitoneal injection of 3 g/kg body wt glucose resulted in a similar increase of plasma glucose concentration in pdk1hmand in pdk1wtmice but led to a higher increase of urinary glucose excretion in pdk1hmmice. In conclusion, reduction of functional PDK-1 leads to impairment of electrogenic intestinal glucose absorption and renal glucose reabsorption. The experiments disclose a novel element of glucose transport regulation in kidney and small intestine.
Modular regulation analysis of heart contraction: application to in situ demonstration of a direct mitochondrial activation by calcium in beating heart
Authors: Diolez Philippe , Deschodt-Arsac Véronique , Raffard Gérard , Simon Cécile , Santos Pierre Dos , Thiaudière Eric , Arsac Laurent , Franconi Jean-Michel
Published: June 2006

Heart contraction is characterized by the absence of changes in energetic intermediates in response to a large increase of activity. Until now no experimental approach could address this question concerning the intact beating heart. Ca2+plays a crucial role in the excitation-contraction coupling, and in vitro studies have evidenced that Ca2+may also directly activate mitochondrial oxidative phosphorylation. We applied our new in situ modular control and regulation analysis on isolated beating rat heart perfused under two different calcium concentrations with pyruvate or glucose as the substrate. Modular control analysis demonstrated experimentally that, although control by energy production was slightly higher under glucose conditions compared with pyruvate, most of the control of heart contraction resides in energy utilization. This behavior is the direct consequence of the high sensitivity (elasticity) of the energy producer processes to ATP utilization. Interestingly, the increase in heart metabolic rate by Ca2+did not significantly change the pattern of control distribution. The regulation analysis performed under the two calcium conditions demonstrated a balanced activation of myofibrils ATPases, and mitochondrial ATP synthesis in response to Ca2+increase. This first study demonstrates in situ the hypothesis that the energetic adequation in heart contraction is mediated by a parallel activation of both processes of energy production and utilization by Ca2+. The results presented here show that modular control and regulation analyses allow in situ study of internal regulations in intact beating heart energetics and function and may now be applied to heart dysfunctions and therapeutic effects.
A murine model for bone loss from therapeutic and space-relevant sources of radiation
Authors: Hamilton S. A. , Pecaut M. J. , Gridley D. S. , Travis N. D. , Bandstra E. R. , Willey J. S. , Nelson G. A. , Bateman T. A.
Published: June 2006

Cancer patients receiving radiation therapy are exposed to photon (gamma/X-ray), electron, and less commonly proton radiation. Similarly, astronauts on exploratory missions will be exposed to extended periods of lower-dose radiation from multiple sources and of multiple types, including heavy ions. Therapeutic doses of radiation have been shown to have deleterious consequences on bone health, occasionally causing osteoradionecrosis and spontaneous fractures. However, no animal model exists to study the cause of radiation-induced osteoporosis. Additionally, the effect of lower doses of ionizing radiation, including heavy ions, on general bone quality has not been investigated. This study presents data developing a murine model for radiation-induced bone loss. Female C57BL/6 mice were exposed to gamma, proton, carbon, or iron radiation at 2-Gray doses, representing both a clinical treatment fraction and spaceflight exposure for an exploratory mission. Mice were euthanized 110 days after irradiation. The proximal tibiae and femur diaphyses were analyzed using microcomputed tomography. Results demonstrate profound changes in trabecular architecture. Significant losses in trabecular bone volume fraction were observed for all radiation species: gamma, (−29%), proton (−35%), carbon (−39%), and iron (−34%). Trabecular connectivity density, thickness, spacing, and number were also affected. These data have clear implications for clinical radiotherapy in that bone loss in an animal model has been demonstrated at low doses. Additionally, these data suggest that space radiation has the potential to exacerbate the bone loss caused by microgravity, although lower doses and dose rates need to be studied.
Polyamine-mediated reduction in human airway epithelial migration in response to wounding is PGE2dependent through decreases in COX-2 and cPLA2protein levels
Authors: Cowan Mark J. , Coll Timothy , Shelhamer James H.
Published: June 2006

Both ornithine decarboxylase inhibition to deplete polyamines and cyclooxygenase inhibition diminish the migration response to injury of human airway epithelial cells in tissue culture monolayers by ∼75%. Restoration of normal migration responses is achieved in the polyamine depleted system either by exogenous reconstitution of polyamines or the addition of prostaglandin E2(PGE2). However, only PGE2was able to restore migration in the cyclooxygenase-inhibited systems. Western blot for cyclooxygenase-2 and cytosolic phospholipase A2protein levels and ELISAs for PGE2secretion demonstrate dramatic increases over 24–48 h after monolayer wounding. These increases are completely abolished by polyamine depletion or cyclooxygenase inhibition. We conclude that polyamine inhibition decreases cellular migration in response to injury in airway epithelial cells at least in part through inhibiting normal PGE2production in response to injury. This may be brought about by decreases in cytosolic phospholipase A2and cyclooxygenase-2 protein levels.