bluuebunny/crossref_metadata_2025 huggingface dataset:
Localization of a Novel Autosomal Recessive Non‐syndromic Hearing Impairment Locus DFNB63 to Chromosome 11q13.3‐q13.4
Authors: Tlili A. , Masmoudi S. , Dhouib H. , Bouaziz S. , Rebeh I. Ben , Chouchen J. , Turki K. , Benzina Z. , Charfedine I. , Drira M. , Ayadi H.
Published: December 2006

Hereditary hearing impairment is the most genetically heterogeneous trait known in humans. So far, 50 published autosomal recessive non‐syndromic hearing impairment (ARNSHI) loci have been mapped, and 23 ARNSHI genes have been identified. Here, we report the mapping of a novel ARNSHI locus, DFNB63, to chromosome 11q13.3‐q13.4 in a large consanguineous Tunisian family. A maximum LOD score of 5.33 was obtained with microsatellite markers D11S916 and D11S4207. Haplotype analysis defined a 5.55 Mb critical region between microsatellite markers D11S4136 and D11S4081. DFNB63 represents the sixth ARNSHI locus mapped to chromosome 11. We positionally excluded MYO7A from being the DFNB63‐causative gene. In addition, the screening of two candidate genes, SHANK2 and KCNE3, failed to reveal any disease‐causing mutations.
Assessing mechanical function of the zygomatic region in macaques: validation and sensitivity testing of finite element models
Authors: Kupczik K. , Dobson C. A. , Fagan M. J. , Crompton R. H. , Oxnard C. E. , O’Higgins P.
Published: December 2006

Crucial to the interpretation of the results of any finite element analysis of a skeletal system is a test of the validity of the results and an assessment of the sensitivity of the model parameters. We have therefore developed finite element models of two crania of Macaca fascicularis and investigated their sensitivity to variations in bone material properties, the zygomatico‐temporal suture and the loading regimen applied to the zygomatic arch. Maximum principal strains were validated against data derived from ex vivo strain gauge experiments using non‐physiological loads applied to the macaque zygomatic arch. Elastic properties of the zygomatic arch bone and the zygomatico‐temporal suture obtained by nanoindentation resulted in a high degree of congruence between experimental and simulated strains. The findings also indicated that the presence of a zygomatico‐temporal suture in the model produced strains more similar to experimental values than a completely separated or fused arch. Strains were distinctly higher when the load was applied through the modelled superficial masseter compared with loading an array of nodes on the arch. This study demonstrates the importance of the accurate selection of the material properties involved in predicting strains in a finite element model. Furthermore, our findings strongly highlight the influence of the presence of craniofacial sutures on strains experienced in the face. This has implications when investigating craniofacial growth and masticatory function but should generally be taken into account in functional analyses of the craniofacial system of both extant and extinct species.
Black bear femoral geometry and cortical porosity are not adversely affected by ageing despite annual periods of disuse (hibernation)
Authors: McGee Meghan E. , Miller Danielle L. , Auger Janene , Black Hal L. , Donahue Seth W.
Published: December 2006

Disuse (i.e. inactivity) causes bone loss, and a recovery period that is 2–3 times longer than the inactive period is usually required to recover lost bone. However, black bears experience annual disuse (hibernation) and remobilization periods that are approximately equal in length, yet bears maintain or increase cortical bone material properties and whole bone mechanical properties with age. In this study, we investigated the architectural properties of bear femurs to determine whether cortical structure is preserved with age in bears. We showed that cross‐sectional geometric properties increase with age, but porosity and resorption cavity density do not change with age in skeletally immature male and female bears. These findings suggest that structural properties substantially contribute to increasing whole bone strength with age in bears, particularly during skeletal maturation. Porosity was not different between skeletally immature and mature bears, and showed minimal regional variations between anatomical quadrants and radial positions that were similar in pattern and magnitude between skeletally immature and mature bears. We also found gender dimorphisms in bear cortical bone properties: females have smaller, less porous bones than males. Our results provide further support for the idea that black bears possess a biological mechanism to prevent disuse osteoporosis.
The Magpie Trial: a randomised trial comparing magnesium sulphate with placebo for pre‐eclampsia. Outcome for children at 18 months
Authors:   Magpie Trial Follow‐Up Study Collaborative Group
Published: December 2006

Objective  To assess the long‐term effects of in utero exposure to magnesium sulphate for children whose mothers had pre‐eclampsia.

Design  Assessment at 18 months of age for children whose mothers were recruited to the Magpie Trial (recruitment 1998–2001 ISRCTN 86938761), which compared magnesium sulphate with placebo.

Setting  Follow‐up of children born at 125 centres in 19 countries across five continents.

Population  A total of 6922 children were born to women randomised before delivery at follow‐up centres. Of these, 2271 were not included for logistic reasons and 168 were excluded (101 at a centre where <20% were contacted, 40 whose death or disability was due to a problem at conception or embryogenesis and 27 whose parent/s opted out). Therefore, 4483 children were included in follow‐up, of whom 3283 (73%) were contacted.

Methods  Assessment by questionnaire, with interview and neurodevelopmental testing of selected children.

Main outcome measures  Death or neurosensory disability at age of 18 months.

Results  Of those allocated magnesium sulphate, 245/1635 (15.0%) were dead or had neurosensory disability at 18 months compared with 233/1648 (14.1%) allocated placebo (relative risk [RR] 1.06, 95% CI 0.90–1.25), and of survivors, 19/1409 (1.3%) had neurosensory disability at 18 months compared with 27/1442 (1.9%) (RR 0.72, 95% CI 0.40–1.29). There were no substantial differences in causes of death or in the risk of individual impairments or disabilities.

Conclusions  The lower risk of eclampsia following prophylaxis with magnesium sulphate was not associated with a clear difference in the risk of death or disability for children at 18 months.
The Magpie Trial: a randomised trial comparing magnesium sulphate with placebo for pre‐eclampsia. Outcome for women at 2 years
Authors:   Magpie Trial Follow‐Up Study Collaborative Group
Published: December 2006

Objective  The aim of this study was to assess long‐term effects for women following the use of magnesium sulphate for pre‐eclampsia.

Design  Assessment at 2–3 years after delivery for women recruited to the Magpie Trial (recruitment in 1998–2001, ISRCTN 86938761), which compared magnesium sulphate with placebo for pre‐eclampsia.

Setting  Follow up after discharge from hospital at 125 centres in 19 countries across five continents.

Population  A total of 7927 women were randomised at the follow‐up centres. Of these women, 2544 were not included for logistic reasons and 601 excluded (109 at a centre where <20% of women were contacted, 466 discharged without a surviving child and 26 opted out). Therefore, 4782 women were selected for follow‐up, of whom 3375 (71%) were traced.

Methods  Questionnaire assessment was administered largely by post or in a dedicated clinic. Interview assessment of selected women was performed.

Main outcome measures  Death or serious morbidity potentially related to pre‐eclampsia at follow up, other morbidity and use of health service resources.

Results  Median time from delivery to follow up was 26 months (interquartile range 19–36). Fifty‐eight of 1650 (3.5%) women allocated magnesium sulphate died or had serious morbidity potentially related to pre‐eclampsia compared with 72 of 1725 (4.2%) women allocated placebo (relative risk 0.84, 95% CI 0.60–1.18).

Conclusions  The reduction in the risk of eclampsia following prophylaxis with magnesium sulphate was not associated with an excess of death or disability for the women after 2 years.
Use of intravenous immunoglobulin for treatment of recurrent miscarriage: a systematic review
Authors: Hutton B , Sharma R , Fergusson D , Tinmouth A , Hebert P , Jamieson J , Walker M
Published: December 2006

Background  Intravenous immunoglobulin (IVIG) is a fractionated blood product whose off‐label use for treating a variety of conditions, including spontaneous recurrent miscarriage, has continued to grow in recent years. Its high costs and short supply necessitate improved guidance on its appropriate applications.

Objective  We conducted a systematic review of randomised controlled trials evaluating IVIG for treatment of spontaneous recurrent miscarriage.

Search strategy  A systematic search strategy was applied to Medline (1966 to June 2005) and the Cochrane Register of Controlled Trials (June 2005).

Selection criteria  We included all randomised controlled trials comparing all dosages of IVIG to placebo or an active control.

Data collection and analysis  Two investigators independently extracted data using a standardised data collection form. Measures of effect were derived for each trial independently, and studies were pooled based on clinical and methodologic appropriateness.

Main results  We identified eight trials involving 442 women that evaluated IVIG therapy used to treat recurrent miscarriage. Overall, IVIG did not significantly increase the odds ratio (OR) of live birth when compared with placebo for treatment of recurrent miscarriage (OR 1.28, 95% CI 0.78–2.10). There was, however, a significant increase in live births following IVIG use in women with secondary recurrent miscarriage (OR 2.71, 95% CI 1.09–6.73), while those with primary miscarriage did not experience the same benefit (OR 0.66, 95% CI 0.35–1.26).

Author’s conclusions  IVIG increased the rates of live birth in secondary recurrent miscarriage, but there was insufficient evidence for its use in primary recurrent miscarriage.
Agreement between hospital records and maternal recall of mode of delivery: Evidence from 12 391 deliveries in the UK Millennium Cohort Study
Authors: Quigley MA , Hockley C , Davidson LL
Published: December 2006

Objective  The objective of this study was to measure the agreement between hospital records and maternal reporting of mode of delivery in a representative UK sample.

Design  Population‐based survey (Millennium Cohort Study).

Setting  UK.

Population  A total of 12 391 singleton infants born in 2000–2002.

Methods  Mothers were interviewed when infants were approximately 9 months old. Information was collected by interview on many obstetric and perinatal factors including mode of delivery. Record linkage to the mother’s delivery hospital records was undertaken in those who gave consent (90%). A matching record was found for 83%. Maternal report and hospital records were compared using mode of delivery classified into three (normal, assisted and caesarean) and six groups. Factors associated with disagreement between the two data sources were identified.

Main outcome measure  Proportion of records in which there was agreement between the two data sources.

Results  Agreement between maternal report and hospital records was at least 94% using six mode of delivery groups and 98% using three groups. Much of the disagreement (57–63%, depending on country) was between forceps and ventouse, and between planned and emergency caesarean. Disagreement was more common in women whose babies were first born and in women not born in the UK.

Conclusion  Our study confirms that maternal reporting of mode of delivery is highly reliable. This is important for clinical staff caring for women and those conducting epidemiological studies. Additional data sources may be necessary to gather reliable data from ethnic minority women, particularly those born outside the UK, or to distinguish forceps from ventouse, or planned from emergency caesarean section.
Should medical students be taught about rape? A survey of UK medical schools
Authors: Koschorke A , Tilzey A , Welch J
Published: December 2006

Rape and other serious sexual assaults are common and result in long‐term morbidity. Increasing numbers are reported but conviction rates are low. Victims of sexual assault present to a wide range of healthcare settings. Good immediate medical care and evidence collection are important in engaging victims with the criminal justice system, avoiding the loss of crucial evidence and minimising long‐term morbidity. Of 21 UK medical schools surveyed, only eight provided teaching about sexual assault and ten provided other forensic teaching. Sixteen schools provided guidance about personal safety. As rape is so common and traumatic, medical schools should seriously consider providing teaching about this area.
p53‐dependent neuronal cell death in a DJ‐1‐deficient zebrafish model of Parkinson's disease
Authors: Bretaud Sandrine , Allen Claire , Ingham Phillip W. , Bandmann Oliver
Published: December 2006

Mutations in DJ‐1 lead to early onset Parkinson's disease (PD). The aim of this study was to elucidate further the underlying mechanisms leading to neuronal cell death in DJ‐1 deficiency in vivo and determine whether the observed cell loss could be prevented pharmacologically. Inactivation of DJ‐1 in zebrafish, Danio rerio, resulted in loss of dopaminergic neurons after exposure to hydrogen peroxide and the proteasome inhibitor MG132. DJ‐1 knockdown by itself already resulted in increased p53 and Bax expression levels prior to toxin exposure without marked neuronal cell death, suggesting subthreshold activation of cell death pathways in DJ‐1 deficiency. Proteasome inhibition led to a further increase of p53 and Bax expression with widespread neuronal cell death. Pharmacological p53 inhibition either before or during MG132 exposure in vivo prevented dopaminergic neuronal cell death in both cases. Simultaneous knockdown of DJ‐1 and the negative p53 regulator mdm2 led to dopaminergic neuronal cell death even without toxin exposure, further implicating involvement of p53 in DJ‐1 deficiency‐mediated neuronal cell loss. Our study demonstrates the utility of zebrafish as a new animal model to study PD gene defects and suggests that modulation of downstream mechanisms, such as p53 inhibition, may be of therapeutic benefit.
BACA: a mitochondrial genome retriever, organizer and visualizer
Authors: ANTAO T. , BEJA‐PEREIRA A. , FONSECA M. M. , HARRIS D. J.
Published: December 2006

Retrieving and organizing data from complete genomes is a time‐consuming task, even more so if the interest lies only in part of the genome (for nongenomic analysis). Furthermore, when comparing several genomes or genes, data retrieval has to be repeated multiple times. We present baca, a software for retrieving, organizing and visualizing multiple mitochondrial genomes. baca takes a GenBank query, retrieves all related genomes and generates multiple fasta files organized both by genomes and genes. A web‐based user interface and an interactive graphical map of all genomes with all genes are also provided. The program is available from http://cibio.up.pt/software/baca.
Development and multiplex PCR amplification of new microsatellite markers for the freshwater fish, ayu (Plecoglossus altivelis)
Authors: HA T. T. T. , OKABE M. , MORISHIMA K. , NAKAYAMA I. , NAGASAWA K. , UMINO T.
Published: December 2006

Multiplex polymerase chain reaction (PCR) technique has recently been applied to gain many advantages in molecular genetics. The present study focused on the development of 15 new microsatellite markers with multiplex PCR systems in ayu, Plecoglossus altivelis, an important freshwater fish in Japan. All loci were followed Mendelian inheritance in 27 F1 progeny except for the one locus. The number of alleles per locus ranged from nine to 44 and the observed heterozygosities ranged from 0.680 to 0.980 in 50 unrelated individuals. The results indicate that these new microsatellite markers are useful for studies of linkage mapping and population genetics for the species.
Simultaneous cloning of multiple nuclear genes by pooling PCR products of variable size: a cost‐effective method of improving efficiency in large‐scale genetic analyses
Authors: ADDISON JASON A.
Published: December 2006

I present a simple approach to overcome the high cost and low efficiency of cloning polymerase chain reaction (PCR) products for individuals in wide‐scale population genetic analyses. The methodology reduces the number of cloning reactions per individual by engineering a suite of genetic markers that differ in size and pooling these PCR products prior to cloning. Alleles from each gene are then recovered by screening transformed bacterial colonies and identifying the inserts corresponding to each gene based on size. I demonstrate the utility of this technique by presenting the results I obtained from cloning four nuclear genes in 118 individuals from three species of sea urchins (Strongylocentrotus purpuratus, S. droebachiensis and S. pallidus). Of the 472 different PCR products I cloned, I recovered at least one allele for 432 of them (91.5%) by screening between 16 and 32 bacterial colonies for each individual. There existed a bias with respect to recovery efficiency: the two largest fragments (1130–800 bp) were recovered 100% of the time, while the two smaller fragments (580–650 bp) were recovered in 85.6% and 81.4% of the experiments, respectively. I discuss the promise of this application for wide‐scale genetic analyses.
Probabilistic Regional Population Forecasts: The Example of Queensland, Australia
Authors: Wilson Tom , Bell Martin
Published: December 2006

The variability of demographic trends at the subnational scale, particularly internal and international migration, renders subnational population forecasting more difficult than at the national scale. Illustrating the uncertainty of the demographic future for subnational regions is therefore a crucial element of any set of subnational population forecasts. However, subnational forecasts are currently prepared using deterministic models, which fail to properly address the issue of demographic uncertainty. The traditional high, medium, and low variants approach employed by many national statistical offices poses a number of problems. Probabilistic population forecasting models have the potential to overcome many of these problems, but these models have so far been limited to national‐level forecasts. This article reports a first attempt to implement a probabilistic approach to subnational population forecasting using a biregional projection framework. The article sets out the forecasting framework, outlines the approach adopted to formulate each of the assumptions, and presents probabilistic forecasts for 2002–2051 for Queensland and the rest of Australia. The forecasts show a two‐thirds probability that Queensland's population in 2051 will be between 5.4 and 7.7 million while the same range for the rest of the country is 18.6 and 22.7 million. The forecasts quantify to what extent greater uncertainty exists about the demographic future at the subnational compared with the national scale.
Using SimBritain to Model the Geographical Impact of National Government Policies
Authors: Ballas Dimitris , Clarke Graham , Dorling Danny , Rossiter David
Published: December 2006

In this article, we use a dynamic spatial microsimulation model of Britain for the analysis of the geographical impact of policies that have been implemented in Britain in the last 10 years. In particular, we show how spatial microsimulation can be used to estimate the geographical and socio‐economic impact of the following policy developments: introduction of the minimum wage, winter fuel payments, working families tax credits, and new child and working credits. This analysis is carried out with the use of the SimBritain model, which is a product of a 3‐year research project aimed at dynamically simulating urban and regional populations in Britain. SimBritain projections are based on a method that uses small area data from past Censuses of the British population in order to estimate small‐area data for 2001, 2011, and 2021.
Leading Indicators and Spatial Interactions: A Crime‐Forecasting Model for Proactive Police Deployment
Authors: Cohen Jacqueline , Gorr Wilpen L. , Olligschlaeger Andreas M.
Published: December 2006

We develop a leading indicator model for forecasting serious property and violent crimes based on the crime attractor and displacement theories of environmental criminology. The model, intended for support of tactical deployment of police resources, is at the microlevel scale; namely, 1‐month‐ahead forecasts over a grid system of 141 square grid cells 4000 feet on a side (with approximately 100 blocks per grid cell). The leading indicators are selected lesser crimes and incivilities entering the model in two ways: (1) as time lags within grid cells and (2) time and space lags averaged over grid cells contiguous to observation grid cells. Our validation case study uses 1.3 million police records from Pittsburgh, Pennsylvania, aggregated over the grid system for a 96‐month period ending in December 1998. The study uses the rolling‐horizon forecast experimental design with forecasts made over the 36‐month period ending in December 1998, yielding 5076 forecast errors per model. We estimated the leading indicator model using a robust linear regression model, a neural network, and a proven univariate, extrapolative forecast method for use as a benchmark in Granger causality testing. We find evidence of both the crime attractor and displacement theories. The results of comparative forecast experiments are that the leading indicator models provide acceptable forecasts that are significantly better than the extrapolative method in three out of four cases, and for the fourth there is a tie but poor forecast performance. The leading indicators find 41–53% of large crime volume changes in the three successful cases. The corresponding workload for police is quite acceptable, with on the average 5.2 potential large change cases per month to investigate and with 31% of such cases being positives.
RETRACTED: Melatonin prevents oxidative stress and changes in antioxidant enzyme expression and activity in the liver of aging rats
Authors: Mauriz José L. , Molpeceres Virginia , García‐Mediavilla María V. , González Paquita , Barrio Juan P. , González‐Gallego Javier
Published: December 2006

Abstract:  This study compared the effects of melatonin supplementation on markers of oxidative stress, and on the activity and expression of antioxidant enzymes in the liver of young (3‐month‐old) and aging (24‐month‐old) rats. Animals were supplemented with melatonin in the drinking water (20 mg/L) for 4 wk. Liver concentration of thiobarbituric‐reactive substances (TBARS), as an index of lipid peroxidation, and the oxidized to reduced glutathione ratio significantly increased in aged rats (+58%), while values did not significantly differ from the young in aged animals receiving melatonin. Significant decreases in the liver activities of Cu,Zn‐superoxide dismutase (SOD) (−25%), cytosolic (−21%) and mitochondrial (−40%) glutathione peroxidase (GPx), and catalase (CAT) (−34%) were found in aged rats. Melatonin abolished these changes and also prevented the reduction of Cu,Zn‐SOD (−33%), cytosolic GPx (−30%), and mitochondrial GPx (−47%) liver protein content as measured by Western blot. Reductions in Cu,Zn‐SOD mRNA (−39%), and GPx mRNA (−86%) levels induced by aging were also abolished by melatonin. In summary, our data indicate that melatonin treatment abrogates oxidative stress in the liver of aged rats, and that prevention of the decreased activity of CAT and the downregulation of Cu,Zn‐SOD and GPx gene expression contribute to this effect.
Factors Related to Induced Abortion among Young Women in Edo State, Nigeria
Authors: Murray Nancy , Winfrey William , Chatterji Minki , Moreland Scott , Dougherty Leanne , Okonofua Friday
Published: December 2006

Sub‐Saharan Africa has the highest death rate from induced abortion in the world, and young women in southern Nigeria are particularly likely to terminate their pregnancies. This study assesses the prevalence of and factors associated with induced abortion among 601 young women aged 15–24 who were surveyed in Edo State, Nigeria, in 2002. We find that 41 percent of all pregnancies reported by the young women surveyed were terminated, and we estimate the age‐specific abortion rate for 15–19‐year‐olds in Edo State at 49 abortions per 1,000 women, which is slightly higher than previous local estimates and nearly double the countrywide estimate for women aged 15–49. We construct explanatory multivariate models to predict the likelihood that a young woman has experienced sexual intercourse, has become pregnant, and has undergone an induced abortion, controlling for important demographic and risk‐behavior factors. Young women unmarried at the time of the interview are found to be significantly more likely than married women to have had an abortion. Young women who have experienced transactional or forced sex are also significantly more likely to report ever having had an abortion, as are young women who have experienced more than one pregnancy. We conclude with suggestions for modifying the content and target populations of behavioral change messages and programs in the area.
Sexual Violence in Lesotho
Authors: Brown Lisanne , Thurman Tonya , Bloem Jeanette , Kendall Carl
Published: December 2006

The magnitude and characteristics of sexual violence in two urban areas of Lesotho are described based on a random household survey of 939 sexually active women aged 18–35. Sexual violence is defined as nonconsensual sex ranging from the use of threats and intimidation to unwanted touching and forced sex. Twenty‐five percent of women surveyed reported ever being physically forced to have sex; 13 percent reported that forced sex was attempted; 31 percent said that they were touched against their will; and 11 percent reported being forced to touch a man's genitals. Boyfriends were the most common perpetrators of actual and attempted forced sex (66 percent and 44 percent, respectively); known community members were the most common perpetrators of touching the respondent against her will (52 percent). Currently married women and those with more education were less likely than others to report that sex was forced upon them by an intimate partner or by another type of perpetrator. Women living in areas where a program raising awareness about sexual violence was ongoing were more likely to report a history of sexual violence. Given the high prevalence of HIV in Lesotho, programs should address women's right to control their sexuality.
Uncovering the chemical enrichment and mass-assembly histories of star-forming galaxies
Authors: Fernandes R. Cid , Asari N. V. , Sodré L. , Stasińska G. , Mateus A. , Torres-Papaqui J. P. , Schoenell W.
Published: December 2006

We explore the mass-assembly and chemical enrichment histories of star-forming galaxies by applying a population synthesis method to a sample of 84828 galaxies from the Sloan Digital Sky Survey Data Release 5. Our method decomposes the entire observed spectrum in terms of a sum of simple stellar populations spanning a wide range of ages and metallicities, thus allowing the reconstruction of galaxy histories. A comparative study of galaxy evolution is presented, where galaxies are grouped on to bins of nebular abundances or mass. We find that galaxies whose warm interstellar medium is poor in heavy elements are slow in forming stars. Their stellar metallicities also rise slowly with time, reaching their current values (Z★∼ 1/3Z⊙) in the last ∼100 Myr of evolution. Systems with metal-rich nebulae, on the other hand, assembled most of their mass and completed their chemical evolution long ago, reaching Z★∼ Z⊙ at lookback times of several Gyr. These same trends, which are ultimately a consequence of galaxy downsizing, appear when galaxies are grouped according to their stellar mass. The reconstruction of galaxy histories to this level of detail out of integrated spectra offers promising prospects in the field of galaxy evolution theories.
Inhibition of Gene Expression and Growth by Antisense Peptide Nucleic Acids in a Multiresistant β-Lactamase-Producing
Klebsiella pneumoniae
Strain
Authors: Kurupati Prathiba , Tan Kevin Shyong Wei , Kumarasinghe Gamini , Poh Chit Laa
Published: December 2006

Klebsiella pneumoniae
causes common and severe hospital- and community-acquired infections with a high incidence of multidrug resistance. The emergence and spread of β-lactamase-producing
K. pneumoniae
strains highlight the need to develop new therapeutic strategies. In this study, we developed antisense peptide nucleic acids (PNAs) conjugated to the (KFF)
3
K peptide and investigated whether they could mediate gene-specific antisense effects in
K. pneumoniae
. No outer membrane permeabilization was observed with antisense PNAs when used alone. Antisense peptide-PNAs targeted at two essential genes,
gyrA
and
ompA
, were found to be growth inhibitory at concentrations of 20 μM and 40 μM, respectively. Mismatched antisense peptide-PNAs with sequence variations of the
gyrA
and
ompA
genes when used as controls were not growth inhibitory. Bactericidal effects exerted by peptide-anti-
gyrA
PNA and peptide-anti-
ompA
PNA on cells were observed within 6 h of treatment. The antisense peptide-PNAs specifically inhibited expression of DNA gyrase subunit A and OmpA from the respective targeted genes in a dose-dependent manner. Both antisense peptide-PNAs cured IMR90 cell cultures that were infected with
K. pneumoniae
(10
4
CFU) in a dose-dependent manner without any noticeable toxicity to the human cells.
Antimicrobial Susceptibility and Synergy Studies of
Burkholderia cepacia
Complex Isolated from Patients with Cystic Fibrosis
Authors: Zhou Juyan , Chen Yunhua , Tabibi Setareh , Alba Luis , Garber Elizabeth , Saiman Lisa
Published: December 2006

Susceptibility (18 antimicrobial agents including high-dose tobramycin) and checkerboard synergy (23 combinations) studies were performed for 2,621 strains of
Burkholderia cepacia
complex isolated from 1,257 cystic fibrosis patients. Minocycline, meropenem, and ceftazidime were the most active, inhibiting 38%, 26%, and 23% of strains, respectively. Synergy was rarely noted (range, 1% to 15% of strains per antibiotic combination).
In Vitro Effects of Antimicrobial Agents on Planktonic and Biofilm Forms of
Staphylococcus lugdunensis
Clinical Isolates
Authors: Frank Kristi L. , Reichert Emily J. , Piper Kerryl E. , Patel Robin
Published: December 2006

Staphylococcus lugdunensis
is an atypically virulent coagulase-negative staphylococcal species associated with acute and destructive infections that often resemble
Staphylococcus aureus
infections. Several types of infection caused by
S. lugdunensis
(e.g., native valve endocarditis, prosthetic joint infection, and intravascular catheter infection) are associated with biofilm formation, which may lead to an inability to eradicate the infection due to the intrinsic nature of biofilms to resist high levels of antibiotics. In this study, planktonic MICs and MBCs and biofilm bactericidal concentrations of 10 antistaphylococcal antimicrobial agents were measured for 15
S. lugdunensis
isolates collected from patients with endocarditis, medical device infections, or skin and soft tissue infections. Planktonic isolates were susceptible to all agents studied, but biofilms were resistant to high concentrations of most of the drugs. However, moxifloxacin was able to kill 73% of isolates growing in biofilms at ≤0.5 μg/ml. Relative to the effect on cell density, subinhibitory concentrations of nafcillin substantially stimulated biofilm formation of most isolates, whereas tetracycline and linezolid significantly decreased biofilm formation in 93 and 80% of isolates, respectively. An unexpected outcome of MBC testing was the observation that vancomycin was not bactericidal against 93% of
S. lugdunensis
isolates, suggesting widespread vancomycin tolerance in this species. These data provide insights into the response of
S. lugdunensis
isolates when challenged with various levels of antimicrobial agents in clinical use.
Site-Specific Reduction of Oxidative and Lipid Metabolism in Adipose Tissue of 3′-Azido-3′-Deoxythymidine-Treated Rats
Authors: Deveaud Catherine , Beauvoit Bertrand , Reynaud Annabel , Bonnet Jacques
Published: December 2006

Although it is well accepted that treatment with some nucleoside reverse transcriptase inhibitors modifies both fat metabolism and fat distribution in humans, the mechanisms underlying these modifications are not yet known. The present investigation examined whether a decrease in oxidative capacity, induced by a chronic oral administration of 3′-azido-3′-deoxythymidine (AZT) in rats, could be associated with an alteration of the lipogenic capacity of white adipose tissues. The impact of obesity as a factor was then evaluated. Results showed that AZT treatment induced differential effects depending on anatomical localization. Indeed, in the inguinal adipose tissue, the specific activities of cytochromecoxidase and fatty acid synthase, two rate-controlling enzymes in energy and lipogenic metabolisms, respectively, both decreased under AZT treatment, thus leading to a lowered cell lipid accumulation. Moreover, the AMP-activated protein kinase phosphorylation level tended to increase, thus implying that AZT causes an energy imbalance. Furthermore, the inguinal tissue of obese rats presented a sensitivity to AZT treatment that was higher than that of lean rats. In contrast, for epididymal tissue, no significant change in all these parameters could be detected under AZT treatment, regardless of the nutritional status of the animals. Taken together, these data demonstrate differential effects of AZT on subcutaneous adipose tissue and visceral white adipose tissue. It could be considered that the chronic decreases in energy and lipogenic metabolism of inguinal adipocyte, consecutive to AZT treatment, may lead, in the long term, to adipose tissue atrophy.
Reduced Susceptibility to Polyenes Associated with a Missense Mutation in the
ERG6
Gene in a Clinical Isolate of
Candida glabrata
with Pseudohyphal Growth
Authors: Vandeputte Patrick , Tronchin Guy , Bergès Thierry , Hennequin Christophe , Chabasse Dominique , Bouchara Jean-Philippe
Published: December 2006

Little information is available about the molecular mechanisms responsible for polyene resistance in pathogenic yeasts. A clinical isolate of
Candida glabrata
with a poor susceptibility to polyenes, as determined by disk diffusion method and confirmed by determination of MIC, was recovered from a patient treated with amphotericin B. Quantitative analysis of sterols revealed a lack of ergosterol and an accumulation of late sterol intermediates, suggesting a defect in the final steps of the ergosterol pathway. Sequencing of Cg
ERG11
, Cg
ERG6
, Cg
ERG5
, and Cg
ERG4
genes revealed exclusively a unique missense mutation in Cg
ERG6
leading to the substitution of a cysteine by a phenylalanine in the corresponding protein. In addition, real-time reverse transcription-PCR demonstrated an overexpression of genes encoding enzymes involved in late steps of the ergosterol pathway. Moreover, this isolate exhibited a pseudohyphal growth whatever the culture medium used, and ultrastructural changes of the cell wall of blastoconidia were seen consisting in a thinner inner layer. Cell wall alterations were also suggested by the higher susceptibility of growing cells to Calcofluor white. Additionally, complementation of this isolate with a wild-type copy of the Cg
ERG6
gene restored susceptibility to polyenes and a classical morphology. Together, these results demonstrated that mutation in the Cg
ERG6
gene may lead to a reduced susceptibility to polyenes and to a pseudohyphal growth due to the subsequent changes in sterol content of the plasma membrane.
Improved Antibacterial Host Defense and Altered Peripheral Granulocyte Homeostasis in Mice Lacking the Adhesion Class G Protein Receptor CD97
Authors: Wang Tao , Tian Linhua , Haino Makoto , Gao Ji-Liang , Lake Ross , Ward Yvona , Wang Hongshan , Siebenlist Ulrich , Murphy Philip M. , Kelly Kathleen
Published: December 2006

CD97 is a member of the adhesion family of G protein-coupled receptors. Alternatively spliced forms of CD97 bind integrins α5β1 and αvβ3, decay accelerating factor, or dermatan sulfate. CD97 is expressed on myeloid cells at high levels and a variety of other cell types at lower levels. Little is known about the physiological function of CD97. To begin dissecting the function of CD97, we evaluated the immune response of CD97 null mice to systemic infection byListeria monocytogenes. CD97 null mice were significantly more resistant to listeriosis than matched wild-type mice. A major determinant of the difference in survival appeared to be the comparatively more robust accumulation of granulocytes in the blood and in infected livers of CD97 null mice within 18 h of inoculation, correlating with a decrease in the number of bacteria. CD97 null mice also displayed a mild granulocytosis in the nonchallenged state. Because there is a strong suggestion that CD97 functions in an adhesive capacity, we examined the migratory properties of granulocytes in CD97 null mice. In chimeric animals, CD97 null and wild-type granulocytes migrated similarly, as determined by inflammation-induced emigration from the bone marrow and accumulation in the peritoneum. Granulocyte development in the bone marrow of CD97 null mice was comparable to that of wild-type mice, and CD97 deficiency did not appear to stimulate granulocytosis secondary to peripheral inflammation and resultant granulocyte colony-stimulating factor induction, unlike various other models of adhesion deficiencies. Our results suggest that CD97 plays a role in peripheral granulocyte homeostasis.
Functional Characterization of thePlasmodium falciparumandP. bergheiHomologues of Macrophage Migration Inhibitory Factor
Authors: Augustijn Kevin D. , Kleemann Robert , Thompson Joanne , Kooistra Teake , Crawford Carina E. , Reece Sarah E. , Pain Arnab , Siebum Arjan H. G. , Janse Chris J. , Waters Andrew P
Published: December 2006

Macrophage migration inhibitory factor (MIF) is a mammalian cytokine that participates in innate and adaptive immune responses. Homologues of mammalian MIF have been discovered in parasite species infecting mammalian hosts (nematodes and malaria parasites), which suggests that the parasites express MIF to modulate the host immune response upon infection. Here we report the first biochemical and genetic characterization of aPlasmodiumMIF (PMIF). Like human MIF, histidine-tagged purified recombinantPMIF shows tautomerase and oxidoreductase activities (although the activities are reduced compared to those of histidine-tagged human MIF) and efficiently inhibits AP-1 activity in human embryonic kidney cells. Furthermore, we found thatPlasmodium bergheiMIF is expressed in both a mammalian host and a mosquito vector and that, in blood stages, it is secreted into the infected erythrocytes and released upon schizont rupture. MutantP. bergheiparasites lackingPMIF were able to complete the entire life cycle and exhibited no significant changes in growth characteristics or virulence features during blood stage infection. However, rodent hosts infected with knockout parasites had significantly higher numbers of circulating reticulocytes. Our results suggest thatPMIF is produced by the parasite to influence host immune responses and the course of anemia upon infection.
Peri-Implant Tissue Is an Important Niche for
Staphylococcus epidermidis
in Experimental Biomaterial-Associated Infection in Mice
Authors: Broekhuizen Corine A. N. , de Boer Leonie , Schipper Kim , Jones Christopher D. , Quadir Shan , Feldman Roger G. , Dankert Jacob , Vandenbroucke-Grauls Christina M. J. E. , Weening Jan J. , Zaat Sebastian A. J.
Published: December 2006

Biomaterial-associated infections (BAI), which are predominantly caused by
Staphylococcus epidermidis
, are a significant problem in modern medicine. Biofilm formation is considered the pivotal element in the pathogenesis, but in previous mouse studies we retrieved
S. epidermidis
from peri-implant tissue. To assess the kinetics and generality of tissue colonization, we investigated BAI using two
S. epidermidis
strains, two biomaterials, and two mouse strains. With small inocula all implants were culture negative, whereas surrounding tissues were positive. When higher doses were used, tissues were culture positive more often than implants, with higher numbers of CFU. This was true for the different biomaterials tested, for both
S. epidermidis
strains, at different times, and for both mouse strains.
S. epidermidis
colocalized with host cells at a distance that was >10 cell layers from the biomaterial-tissue interface. We concluded that in mouse experimental BAI
S. epidermidis
peri-implant tissue colonization is more important than biofilm formation.
Enterohemorrhagic
Escherichia coli
O157:H7
gal
Mutants Are Sensitive to Bacteriophage P1 and Defective in Intestinal Colonization
Authors: Ho Theresa Deland , Waldor Matthew K.
Published: December 2006

Enterohemorrhagic
Escherichia coli
(EHEC), especially
E. coli
O157:H7, is an emerging cause of food-borne illness. Unfortunately,
E. coli
O157 cannot be genetically manipulated using the generalized transducing phage P1, presumably because its extensive O antigen obscures the P1 receptor, the lipopolysaccharide (LPS) core subunit. The GalE, GalT, GalK, and GalU proteins are necessary for modifying galactose before it can be assembled into the repeating subunit of the O antigen. Here, we constructed
E. coli
O157:H7
gal
mutants which presumably have little or no O antigen. These strains were able to adsorb P1. P1 lysates grown on the
gal
mutant strains could be used to move chromosomal markers between EHEC strains, thereby facilitating genetic manipulation of
E. coli
O157:H7. The
gal
mutants could easily be reverted to a wild-type Gal
+
strain using P1 transduction. We found that the O157:H7
galETKM
::
aad-7
deletion strain was 500-fold less able to colonize the infant rabbit intestine than the isogenic Gal
+
parent, although it displayed no growth defect in vitro. Furthermore, in vivo a Gal
+
revertant of this mutant outcompeted the
galETKM
deletion strain to an extent similar to that of the wild type. This suggests that the O157 O antigen is an important intestinal colonization factor. Compared to the wild type, EHEC
gal
mutants were 100-fold more sensitive to a peptide derived from bactericidal permeability-increasing protein, a bactericidal protein found on the surface of intestinal epithelial cells. Thus, one way in which the O157 O antigen may contribute to EHEC intestinal colonization is to promote resistance to host-derived antimicrobial polypeptides.
Proteomic Analysis of Outer Membranes and Vesicles from Wild-Type Serogroup B
Neisseria meningitidis
and a Lipopolysaccharide-Deficient Mutant
Authors: Williams Jeannette N. , Skipp Paul J. , Humphries Holly E. , Christodoulides Myron , O'Connor C. David , Heckels John E.
Published: December 2006

Current experimental vaccines against serogroup B
Neisseria meningitidis
are based on meningococcal outer membrane (OM) proteins present in outer membrane vesicles (OMV) in which toxic lipopolysaccharide is depleted by detergent extraction. Knowledge of the composition of OM and OMV is essential for developing new meningococcal vaccines based on defined antigens. In the current study, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and nanocapillary liquid chromatography-tandem mass spectrometry were used to investigate the proteomes of OM and OMV from meningococcal strain MC58 and OM from a lipopolysaccharide-deficient mutant. The analysis of OM revealed a composition that was much more complex than the composition that has been reported previously; a total of 236 proteins were identified, only 6.4% of which were predicted to be located in the outer membrane. The most abundant proteins included not only the well-established major OM proteins (PorA, PorB, Opc, Rmp, and Opa) but also other proteins, such as pilus-associated protein Q (PilQ) and a putative macrophage infectivity protein. All of these proteins were also present in OMV obtained by extraction of the OM with deoxycholate. There were markedly increased levels of some additional proteins in OM from the lipopolysaccharide-deficient mutant, including enzymes that contribute to the tricarboxylic acid cycle. In all the preparations, the proteins not predicted to have an OM location were predominantly periplasmic or cytoplasmic or had an unknown location, and relatively few cytoplasmic membrane proteins were detected. However, several proteins that have previously been identified as potential vaccine candidates were not detected in either OM preparations or in OMV. These results have important implications for the development and use of vaccines based on outer membrane proteins.
Enhanced Protection against Malaria by a Chimeric Merozoite Surface Protein Vaccine
Authors: Shi Qifang , Lynch Michelle M. , Romero Margarita , Burns James M.
Published: December 2006

The 42-kDa processed fragment ofPlasmodium falciparummerozoite surface protein 1 (MSP-142) is a prime candidate for a blood-stage malaria vaccine. Merozoite surface protein 8 contains two C-terminal epidermal growth factor (EGF)-like domains that may function similarly to those of MSP-142. Immunization with either MSP-1 or MSP-8 induces protection that is mediated primarily by antibodies against conformation-dependent epitopes. In a series of comparative immunogenicity and efficacy studies using thePlasmodium yoeliirodent model, we tested the ability of recombinantP. yoeliiMSP-8 (rPyMSP-8) to complement rPyMSP-1-based vaccines. Unlike MSP-1, PyMSP-8-dependent protection required immunization with the full-length protein and was not induced with recombinant antigens that contained only the C-terminal EGF-like domains. Unlike PyMSP-8, the immunogenicity of the PyMSP-1 EGF-like domains was low when present as part of the rPyMSP-142antigen. Immunization with a mixture of rPyMSP-142and rPyMSP-8 further inhibited the antibody response to protective epitopes of rPyMSP-142and did not improve vaccine efficacy. To improve PyMSP-1 immunogenicity, we produced a chimeric antigen containing the EGF-like domains of PyMSP-1 fused to the N terminus of PyMSP-8. Immunization with the chimeric rPyMSP-1/8 antigen induced high and comparable antibody responses against the EGF-like domains of both PyMSP-1 and PyMSP-8. This enhanced MSP-1-specific antibody response and the concurrent targeting of MSP-1 and MSP-8 resulted in improved, nearly complete protection against lethalP. yoelii17XL malaria. Unexpectedly, immunization with rPyMSP-1/8 failed to protect against challenge infection with reticulocyte-restrictedP. yoelii17X parasites. Overall, these data establish an effective strategy to improve the efficacy ofP. falciparumMSP-based vaccines.