bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling ground thermal conditions and the limit of permafrost within the nearshore zone of the Mackenzie Delta, Canada
Authors: Stevens Christopher W. , Moorman Brian J. , Solomon Steve M.
Published: December 2010

This study examines the interrelated effects of snow and ice on ground thermal conditions beneath regions of shallow water within the nearshore zone of the Mackenzie Delta. Field‐ and model‐based data were used to determine the thermal boundary conditions at the sediment bed surface and to define the contemporary limit of permafrost. Over two consecutive winters, mean sediment bed temperatures deviated up to 9.8°C beneath bottom‐fast ice that ranged from 10 cm to 100 cm thick, with intrasite variability as much as 4.7°C. Measured and modeled temperatures were found to exponentially relate to the duration of time ice is bottom‐fast with the sediment bed. Mean winter ground temperatures at this boundary were predicted within ±0.25°C of the observed measurements using numerical thermal modeling. As on‐ice snow depth decreased, the limit of equilibrium permafrost shifted toward progressively deeper water because of longer durations of ice contact and greater heat loss from the ground. The critical water depth for permafrost under equilibrium conditions was 84 cm (calculated from an ice thickness of 93 cm), which is equivalent to an ice contact time of 142 days. Equilibrium permafrost was mapped beneath 393.8 km2 of bottom‐fast ice. An additional 387.9 km2 exhibited seasonal ground freezing in the winter of 2006–2007. Areas affected by bottom‐fast ice represent locations that are actively receiving sediment from distributary channels. These results provide the first estimates of contemporary permafrost distribution for shallow water regions of the outer Mackenzie Delta.
Protein tyrosine kinase 7 has a conserved role in Wnt/β‐catenin canonical signalling
Authors: Puppo Francesca , Thomé Virginie , Lhoumeau Anne‐Catherine , Cibois Marie , Gangar Akanksha , Lembo Frédérique , Belotti Edwige , Marchetto Sylvie , Lécine Patrick , Prébet Thomas , Sebbagh Michael , Shin Won‐Sik , Lee Seung‐Taek , Kodjabachian Laurent , Borg Jean‐Paul
Published: December 2010

The receptor protein tyrosine kinase 7 (PTK7) was recently shown to participate in noncanonical Wnt/planar cell polarity signalling during mouse and frog embryonic development. In this study, we report that PTK7 interacts with β‐catenin in a yeast two‐hybrid assay and mammalian cells. PTK7‐deficient cells exhibit weakened β‐catenin/T‐cell factor transcriptional activity on Wnt3a stimulation. Furthermore, Xenopus PTK7 is required for the formation of Spemann's organizer and for Siamois promoter activation, events that require β‐catenin transcriptional activity. Using epistatic assays, we demonstrate that PTK7 functions upstream from glycogen synthase kinase 3. Taken together, our data reveal a new and conserved role for PTK7 in the Wnt canonical signalling pathway.
Chromatin modification acts as a memory for systemic acquired resistance in the plant stress response
Authors: Jaskiewicz Michal , Conrath Uwe , Peterhänsel Christoph
Published: December 2010

Priming of defence genes for amplified response to secondary stress can be induced by application of the plant hormone salicylic acid or its synthetic analogue acibenzolar S‐methyl. In this study, we show that treatment with acibenzolar S‐methyl or pathogen infection of distal leaves induce chromatin modifications on defence gene promoters that are normally found on active genes, although the genes remain inactive. This is associated with an amplified gene response on challenge exposure to stress. Mutant analyses reveal a tight correlation between histone modification patterns and gene priming. The data suggest a histone memory for information storage in the plant stress response.
Yox1 links MBF‐dependent transcription to completion of DNA synthesis
Authors: Gómez‐Escoda Blanca , Ivanova Tsvetomira , Calvo Isabel A , Alves‐Rodrigues Isabel , Hidalgo Elena , Ayté José
Published: December 2010

When DNA replication is challenged cells activate a DNA synthesis checkpoint, blocking cell cycle progression until they are able to overcome the replication defects. In fission yeast, Cds1 is the effector kinase of this checkpoint, inhibiting M‐phase entry, stabilizing stalled replication forks and triggering transcriptional activation of S‐phase genes. The molecular basis of this last effect is largely unknown. The Mlu1 binding factor (MBF) complex controls the transcription of S‐phase genes. We purified novel interactors of the MBF complex and identified the repressor Yox1. When the DNA synthesis checkpoint is activated, Yox1 is phosphorylated, which abrogates its binding to MBF. MBF‐dependent transcription therefore remains active until cells are able to overcome this challenge.
An investigation on the influence of feline flea allergy on the fecundity of the cat flea
Authors: McDonald B.J. , Foil C.S. , Foil L.D.
Published: December 2010

Survival, egg production and egg viability of fleas allowed to feed on eight flea‐allergic and six flea‐naive cats were compared. Fifty fleas, in feeding cages or free roaming, were allowed to feed on the cats. Flea‐allergic cats removed significantly more free‐roaming fleas than did flea‐naive cats. Female fleas produced fewer eggs on flea‐allergic cats than on flea‐naive cats regardless of feeding method. There was no significant difference in egg viability between the two groups. The data suggest that flea‐allergic cats efficiently removed fleas by grooming and that they also produce unknown factor(s) that affect the fecundity of fleas.
Science Education Policy: A Symposium
Authors: KUMAR DAVID D. , ALTSCHULD JAMES W.
Published: December 2010

This article introduces Science Education Policy: A Symposium. The symposium examines trends and issues from the vantage points of individuals from a variety of backgrounds who are concerned with science education in the US. Although optimistic, most of the contributors to this symposium agree that considerable research and evaluation is still needed before we can make informed policy decisions that would have a lasting impact on science education. The expected outcome of the symposium is to stimulate discussions among educators and policymakers.
Intraurban Location of Producer Services in Guangzhou, China
Authors: Yi Hong , Yang Fiona F , Yeh Anthony G O
Published: December 2010

The location of producer services has significant implications on the restructuring of the urban landscape. It is well documented that the growth of producer services in advanced economies has tended to be highly concentrated in the city proper, while at the same time demonstrating a prevailing tendency toward decentralization in recent years because of the development of information and communication technology. Producer services have been growing rapidly in urban China over the past decade. They have created new and remarkable changes in ‘postsocialist cities’. This study analyzes the intraurban location of information and consulting services in Guangzhou, China. The findings suggest that the distribution pattern of producer services has gradually changed from dispersed to centripetal development towards the new business district. This is in stark contrast with the situation in Western cities. In Ghangzhou, urban land reform, city planning, and the need for producer services to gain more prestige and business linkages have together shaped new location dynamics for producer services. There has been a transformation from the once dispersed pattern into one that is more concentrated.
Top tips for embedding chronic condition self-management support into practice
Authors: Lawn Sharon
Published: December 2010

Organisational change aimed at service improvement continues to be a challenging process for many health services, managers and teams. Current imperatives to develop service models responsive to the growing demands of chronic conditions on health systems suggest that reflection on core change principles is warranted. Dominant themes for progress in embedding chronic condition self-management (CCSM) support into practice settings arose from content analyses of case studies from health professionals who have attempted to implement CCSM support into their health services after undertaking specific training (The Flinders Program of CCSM). This included in-depth interviews with 10 trainers accredited to deliver training in this CCSM care planning approach to the workforce, formal reflections from 47 postgraduate students (currently in the health workforce) enrolled in a dedicated CCSM program at Flinders University and a consensus forum with accredited trainers. Emergent themes were then considered in the context of existing organisational change and CCSM literature. Long understood principles of effective change management continue to be important, including leadership support, clear vision, team cohesion, effective people management and shared values. However, interdependence of these and other factors seems to be most important. Organisational change that builds capacity for CCSM support is possible, given a clearer understanding of where efforts will have the most positive impact on change.
Program logic: a framework for health program design and evaluation - the Pap nurse in general practice program
Authors: Hallinan Christine M.
Published: December 2010

In this paper, program logic will be used to ‘map out’ the planning, development and evaluation of the general practice Pap nurse program in the Australian general practice arena. The incorporation of program logic into the evaluative process supports a greater appreciation of the theoretical assumptions and external influences that underpin general practice Pap nurse activity. The creation of a program logic model is a conscious strategy that results an explicit understanding of the challenges ahead, the resources available and time frames for outcomes. Program logic also enables a recognition that all players in the general practice arena need to be acknowledged by policy makers, bureaucrats and program designers when addressing through policy, issues relating to equity and accessibility of health initiatives. Logic modelling allows decision makers to consider the complexities of causal associations when developing health care proposals and programs. It enables the Pap nurse in general practice program to be represented diagrammatically by linking outcomes (short, medium and long term) with both the program activities and program assumptions. The research methodology used in the evaluation of the Pap nurse in general practice program includes a descriptive study design and the incorporation of program logic, with a retrospective analysis of Australian data from 2001 to 2009. For the purposes of gaining both empirical and contextual data for this paper, a data set analysis and literature review was performed. The application of program logic as an evaluative tool for analysis of the Pap PN incentive program facilitates a greater understanding of complex general practice activity triggers, and also allows this greater understanding to be incorporated into policy to facilitate Pap PN activity, increase general practice cervical smear and ultimately decrease burden of disease.
Who regulates food? Australians' perceptions of responsibility for food safety
Authors: Henderson Julie , Coveney John , Ward Paul
Published: December 2010

Food scares have diminished trust in public institutions to guarantee food safety. Food governance after the food scare era is concerned with institutional independence and transparency leading to a hybrid of public and private sector management and to mechanisms for consumer involvement in food governance. This paper explores Australian consumers’ perceptions of who is, and should be responsible for food safety. Forty-seven participants were interviewed as part of a larger study on trust in the food system. Participants associate food governance with government, industry, and the individual. While few participants can name the national food regulator, there is a strong belief that the government is responsible for regulating the quality and safety of food. Participants are wary of the role of the food industry in food safety, believing that profit motives will undermine effective food regulation. Personal responsibility for food safety practices was also identified. While there are fewer mechanisms for consumer involvement and transparency built into the food governance system, Australian consumers display considerable trust in government to protect food safety. There is little evidence of the politicisation of food, reflecting a level of trust in the Australian food governance system that may arise from a lack of exposure to major food scares.
Nutrition in general practice: role and workforce preparation expectations of medical educators
Authors: Ball Lauren E. , Hughes Roger M. , Leveritt Michael D.
Published: December 2010

Nutrition advice from general practitioners (GPs) is held in high regard by the general public, yet the literature investigating the role of GPs in the provision of nutrition care is limited. This qualitative study aimed to explore the perceptions of general practice medical educators (GPMEs) regarding the role of GPs in general practice nutrition care, the competencies required by GPs to provide effective nutrition care and the learning and teaching strategies best suited to develop these competencies. Twenty medical educators from fourteen Australian and New Zealand universities participated in an individual semi-structured telephone interview, guided by an inquiry logic informed by the literature. Interviews were transcribed verbatim and thematically analysed. Medical educators identified that nutrition was an important but mostly superficially addressed component of health care in general practice. Numerous barriers to providing nutrition care in general practice were identified. These include a lack of time and associated financial disincentives, perceptions of inadequate skills in nutrition counselling associated with inadequate training, ambiguous attitudes and differing perceptions about the role of GPs in the provision of nutrition care. Further research is required to identify strategies to improve nutrition care and referral practices provided in the general practice setting, in order to utilise the prime position of GPs as gatekeepers of integrated care to the general public.
Engaging primary health care workers in drug and alcohol and mental health interventions: challenges for service delivery in rural and remote Australia
Authors: Allan Julaine
Published: December 2010

Access to drug and alcohol treatment services is a particularly salient issue for Australia. The nation is paying considerable attention to risky drug and alcohol use. Indigenous Australians are particularly concerned about drug and alcohol related harms in their communities. Access to treatment is the most effective way of reducing drug related harm for disadvantaged populations. Primary health care is the optimal site for delivering drug and alcohol treatment. Semi-structured in-depth interviews with 47 primary health care, drug and alcohol and other health and welfare workers in rural and remote locations were conducted. Thematic analysis of interview data identified divergent perspectives according to a participant’s work role about drug and alcohol treatment, client needs and problems and service delivery approaches. Primary health care workers were conceptualised as locals. They tended to perceive that drug and alcohol interventions should quickly prevent individuals from on-going problematic use. Drug and alcohol workers were conceptualised as insiders. Most did not have knowledge or experience of the primary health care setting. Therefore they could not assist primary health care workers to integrate drug and alcohol interventions into their interactions with clients. Professional and organisational barriers constrain the primary health care worker role and limit the application of specialist interventions. Drug and alcohol work is only one of many competing demands in the primary health setting. The lack of understanding of the primary health care worker role and responsibilities is the most significant barrier to implementing specialist interventions in this role. Primary health care workers’ perceptions of substance misuse are more consistent with the individual moral or personal deficit philosophy of drug and alcohol treatment than harm minimisation approaches. This is a challenge for a specialist agency that is promoting harm minimisation and an adaptive approach to treatment within the primary care setting. Building the capacity of primary health care workers to do more varied tasks requires a good understanding of the pragmatic and practical realities of their day to day practice and the philosophies that underpin these.
Primary oral health service provision in Aboriginal Medical Services-based dental clinics in Western Australia
Authors: Kruger Estie , Perera Irosha , Tennant Marc
Published: December 2010

Australians living in rural and remote areas have poorer access to dental care. This situation is attributed to workforce shortages, limited facilities and large distances to care centres. Against this backdrop, rural and remote Indigenous (Aboriginal) communities in Western Australia seem to be more disadvantaged because evidence suggests they have poorer oral health than non-Indigenous people. Hence, provision of dental care for Aboriginal populations in culturally appropriate settings in rural and remote Western Australia is an important public health issue. The aim of this research was to compare services between the Aboriginal Medical Services (AMS)-based clinics and a typical rural community clinic. A retrospective analysis of patient demographics and clinical treatment data was undertaken among patients who attended the dental clinics over a period of 6 years from 1999 to 2004. The majority of patients who received dental care at AMS dental clinics were Aboriginal (95.3%), compared with 8% at the non-AMS clinic. The rate of emergency at the non-AMS clinic was 33.5%, compared with 79.2% at the AMS clinics. The present study confirmed that more Indigenous patients were treated in AMS dental clinics and the mix of dental care provided was dominated by emergency care and oral surgery. This indicated a higher burden of oral disease and late utilisation of dental care services (more focus on tooth extraction) among rural and remote Indigenous people in Western Australia.
Automated Surveillance of Clostridium difficile Infections Using BioSense
Authors: Benoit Stephen R. , McDonald L. Clifford , English Roseanne , Tokars Jerome I.
Published: December 2010

Objective.

To determine the feasibility of using electronic laboratory and admission-discharge-transfer data from BioSense, a national automated surveillance system, to apply new modified Clostridium difficile infection (CDI) surveillance definitions and calculate overall and facility-specific rates of disease.

Design.

Retrospective, multicenter cohort study.

Setting.

Thirty-four hospitals sending inpatient, emergency department, and /or outpatient data to BioSense.

Methods.

Laboratory codes and text-parsing methods were used to extract C. difficile-positive toxin assay results from laboratory data sent to BioSense during the period from January 1, 2007, through June 30, 2008; these were merged with administrative records to determine whether cases were community associated or healthcare onset, as well as patient-day data for rate calculations. A patient was classified as having hospital-onset CDI if he or she had a C. difficile toxin-positive result on a stool sample collected 3 or more days after admission and community-onset CDI if the specimen was collected less than 3 days after admission or the patient was not hospitalized.

Results.

A total of 4,585 patients from 34 hospitals in 12 states had C. difficile-positive assay results. More than half (53.0%) of the cases were community-onset, and 30.8% of these occurred in patients who were recently hospitalized. The overall rate of healthcare-onset CDI was 7.8 cases per 10,000 patient-days, with a range among facilities of 1.5-27.8 cases per 10,000 patient-days.

Conclusions.

Electronic laboratory data sent to the BioSense surveillance system were successfully used to produce disease rates of CDI comparable to those of other studies, which shows the feasibility of using electronic laboratory data to track a disease of public health importance.
Dissemination and Sustainability of a Hospital-Wide Hand Hygiene Program Emphasizing Positive Reinforcement
Authors: Mayer Jeanmarie , Mooney Barbara , Gundlapalli Adi , Harbarth Stephan , Stoddard Gregory J , Rubin Michael A. , Eutropius Louise , Brinton Britt , Samore Matthew H.
Published: December 2010

Objective.

To increase and sustain hospital-wide compliance with hand hygiene through a long-term ongoing multidimensional improvement program emphasizing behavioral factors.

Design.

Quasi-experimental short study (August 2000-November 2001) and descriptive time series (April 2003-December 2006).

Setting.

A 450-bed teaching tertiary-care hospital.

Interventions.

An initial intervention bundle was introduced in pilot locations that addressed cognitive behavioral factors, which included access to alcohol sanitizer, education, and ongoing audit and feedback. The bundle was subsequently disseminated hospital-wide, along with a novel approach focused on behavior modification through positive reinforcement and annually changing incentives.

Results.

A total of 36,123 hand hygiene opportunities involving all categories of healthcare workers from 12 inpatient units were observed from October 2000 to October 2006. The rate of compliance with hand hygiene significantly improved after the intervention in 2 cohorts over the first year (from 40% to 64% of opportunities and from 34% to 49% of opportunities;P< .001, compared with the control group). Mean compliance rates ranged from 19% to 41% of 4174 opportunities (at baseline), increased to the highest levels of 73%–84% of 6,420 opportunities 2 years after hospital-wide dissemination, and remained improved at 59%–81% of 4,990 opportunities during year 6 of the program.

Conclusion.

This interventional cohort study used a behavioral change approach and is one of the earliest and largest institution-wide programs promoting alcohol sanitizer from the United States that has shown significant and sustained improvements in hand hygiene compliance. This creative campaign used ongoing frequent audit and feedback with novel use of immediate positive reinforcement at an acceptable cost to the institution.
Determination of electron density and temperature in a capacitively coupled RF discharge in neon by OES complemented with a CR model
Authors: Navrátil Z , Dvořák P , Brzobohatý O , Trunec D
Published: December 2010

A method of determination of electron temperature and electron density in plasmas based on optical emission spectroscopy complemented with collisional–radiative modelling (OES/CRM) was studied in this work. A radiofrequency (13.56 MHz) capacitively coupled discharge in neon at 10 Pa was investigated by intensity calibrated optical emission spectroscopy. The absolute intensities of neon transitions between 3p and 3s states were fitted with a collisional–radiative (CR) model in order to determine the electron temperature and electron density. Measuring techniques such as imaging with an ICCD camera were adopted for supplementary diagnostics. The obtained results were compared with the results of compensated Langmuir probe measurement and one-dimensional particle-in-cell/Monte Carlo (PIC/MC) simulation.

The results of OES/CRM and PIC/MC method were in close agreement in the case of electron temperature in the vicinity of a driven electrode. The determined value of electron temperature was about 8 eV. In bulk plasma, the measured spectra were not satisfactorily fitted. In the case of electron density only relative agreement was obtained between OES/CRM and Langmuir probe measurement; the absolute values differed by a factor of 5. The axial dependence of electron density calculated by PIC/MC was distinct from them, reaching the maximum values between the results of the other two methods. The investigation of power dependence of plasma parameters close to the driven electrode showed a decrease in electron temperature and an increase in electron density together with increasing incoming RF power. The calculated spectra fitted very well the measured spectra in this discharge region.
Surface corona-bar discharges for production of pre-ionizing UV light for pulsed high-pressure plasmas
Authors: Xiong Zhongmin , Kushner Mark J
Published: December 2010

Multi-atmospheric pressure, pulsed electric discharge excited lasers require pre-ionization to produce spatially uniform glows. Many such systems use corona bars to produce ultraviolet (UV) and vacuum ultraviolet (VUV) light as photo-ionization sources for this purpose. Corona bars are transient surface discharges, typically in a cylindrical geometry, that sustain high electron temperatures and so are efficient UV and VUV sources. In this paper, results from a numerical study of surface corona-bar discharges in a multi-atmosphere pressure Ne/Xe gas mixture are discussed. The discharge consists of a high-voltage electrode placed on the surface of a corona bar which is a dielectric tube surrounding a cylindrical metal electrode. After the initial breakdown an ionization front propagates along the circumference of the corona bar and produces a thin plasma sheet near the dielectric surface. The propagation speed of the ionization front ranges from 2 × 107 to 3.5 × 108 cm s−1, depending on the applied voltage and dielectric constant of the corona-bar insulator. As the discharge propagates around the circumference, the surface of the corona-bar is charged. The combined effects of surface curvature and charge deposition result in a non-monotonic variation of the electric field and electron temperature as the ionization front traverses the circumference. The UV fluxes collected on a surrounding circular surface correlate with the motion of the ionization front but with a time delay due to the relatively long lifetime of the precursor to the emitting species
.
A study of the plasma electronegativity in an argon–oxygen pulsed-dc sputter magnetron
Authors: You S D , Dodd R , Edwards A , Bradley J W
Published: December 2010

Using Langmuir probe-assisted laser photodetachment, the temporal evolution of the O− density was determined in the bulk plasma of a unipolar pulsed-dc magnetron. The source was operated in reactive mode, at a fixed nominal on-time power of 100 W, sputtering Ti in argon–oxygen atmospheres at 1.3 Pa pressure, but over a variation of duty cycles from 5% to 50% and oxygen partial pressures of 10% and 50% of the total pressure.

In the plasma on-time, for all duty cycles the negative ion density (n
−) rises marginally reaching values typically less than 2 × 1015 m−3 with negative ion-to-electron density ratios, α < 1. However, immediately after the transition from pulse on-to-off, n
− falls by about 20–30% as fast O− species created at the cathode exit the system. This is followed by a rapid rise in n
− to values at least 2 or 3 times that in the on-time. The rate of rise of n
− and its maximum value both increase with decreasing duty cycle. In the off-time, the electron density falls rapidly (initial decay rates of several tens of μs), and therefore the afterglow plasma becomes highly electronegative, with α reaching 4.6 and 14.4 for 10% and 50% oxygen partial pressure, respectively. The rapid rise in n
− in the afterglow (in which the electron temperature falls from about 5 to 0.5 eV) is attributed to the dissociative attachment of highly excited oxygen metastables, which themselves are created in the pulse on-time. At the lowest duty of 5%, the long-term O− decay times are several hundred μs.

Langmuir probe characteristics show the clear signature that negative ions dominate over the electrons in the off-time. From the ion and electron saturation current ratios, α has been estimated in some chosen cases and found to agree within a factor between 2 and 10 with those obtained more directly from the photodetachment method.
Transport behaviours and nanoscopic resistance profiles of electrically stressed Pt/TiO2/Ti planar junctions
Authors: Kim Haeri , Kim Dong-Wook , Phark Soo-Hyon
Published: December 2010

Using Pt/TiO2/Ti planar junctions fabricated with micrometre-sized gaps between electrodes, we found that the application of a bias voltage between the electrodes significantly decreased the resistance of the junction. The nanoscopic resistance profile revealed that the electrical stress modified the bulk as well as the contact resistance. Electrostatic force microscopy was used to investigate the charge distribution and its time evolution in local areas scanned by positively biased Pt-coated tips. Comparative investigations of the transport and scanning probe microscopy results suggest that the electrical stress induced a redistribution of ions, which then modified the junctions' transport characteristics.
Cascade electric field enhancements around small nanorods of brush-shaped nanostructures
Authors: Zhang Z-Y , Zhang Z-D , Wang H-Y , Xiong Z-H
Published: December 2010

The optical properties of brush-shaped nanostructures are calculated by the discrete dipole approximation method. The results show that the E fields around the small vertical nanorods of the brush-shaped nanostructures are significantly enhanced due to the E field couplings between adjacent vertical nanorods. In addition, the heights of the large vertical nanorods dramatically affect the E field couplings and enhancements around the small vertical nanorods. These results would help to understand the large surface-enhanced Raman scattering (SERS) enhancements and the height-dependent SERS properties of nanorod array substrates prepared by the oblique angle deposition method.
Comment on ‘On the origin dependence of multipole moments in electromagnetism’
Authors: Raab R E , de Lange O L
Published: December 2010

We respond to criticism by de Visschere 2006 J. Phys. D: Appl. Phys.
39 4278 of our theory of electromagnetic response fields
D
(
E
,
B
) and
H
(
E
,
B
) for a linear anisotropic medium: our theory produces physically acceptable results for properties such as the material constants, energy flow in the bulk and reflected intensities, whereas that of de Visschere (which is related to ours by a gauge transformation of
D
and
H
) does not.
Virulence of an emerging respiratory pathogen, genus Pandoraea, in vivo and its interactions with lung epithelial cells
Authors: Costello Anne , Herbert Gillian , Fabunmi Lydia , Schaffer Kirsten , Kavanagh Kevin A. , Caraher Emma M. , Callaghan Máire , McClean Siobhán
Published: December 2010

Pandoraea species have emerged as opportunistic pathogens among cystic fibrosis (CF) and non-CF patients. Pandoraea
pulmonicola is the predominant Pandoraea species among Irish CF patients. The objective of this study was to investigate the pathogenicity and potential mechanisms of virulence of Irish P. pulmonicola isolates and strains from other Pandoraea species. Three patients from whom the P. pulmonicola isolates were isolated have since died. The in vivo virulence of these and other Pandoraea strains was examined by determining the ability to kill Galleria mellonella larvae. The P. pulmonicola strains generally were the most virulent of the species tested, with three showing a comparable or greater level of virulence in vivo relative to another CF pathogen, Burkholderia cenocepacia, whilst strains from two other species, Pandoraea
apista and Pandoraea
pnomenusa, were considerably less virulent. For all Pandoraea species, whole cells were required for larval killing, as cell-free supernatants had little effect on larval survival. Overall, invasive Pandoraea strains showed comparable invasion of two independent lung epithelial cell lines, irrespective of whether they had a CF phenotype. Pandoraea strains were also capable of translocation across polarized lung epithelial cell monolayers. Although protease secretion was a common characteristic across the genus, it is unlikely to be involved in pathogenesis. In conclusion, whilst multiple mechanisms of pathogenicity may exist across the genus Pandoraea, it appears that lung cell invasion and translocation contribute to the virulence of P. pulmonicola strains.
Increasing imipenem resistance and dissemination of the ISAba1-associated bla
OXA-23 gene among Acinetobacter baumannii isolates in an intensive care unit
Authors: He Chao , Xie Yi , Zhang Lei , Kang Mei , Tao Chuanmin , Chen Zhixing , Lu Xiaojun , Guo Liang , Xiao Yuling , Duo Lina , Fan Hong
Published: December 2010

The antibiotic susceptibility of Acinetobacter calcoaceticus–Acinetobacter baumannii complex strains recovered from the intensive care unit (ICU) of West China Hospital, Sichuan, PR China, from 2006 to 2009 was investigated. The identification of A. baumannii and analysis of carbapenemase-encoding genes and their relationship with ISAba1 were performed by PCR. Furthermore, a DiversiLab repetitive extragenic palindromic sequence-based PCR (rep-PCR) microbial typing system and a multilocus sequence typing (MLST) scheme were applied to assess the genetic relationship of the isolates. The results showed that the antibiotic susceptibility of the A. calcoaceticus–A. baumannii complex isolates changed and imipenem resistance increased rapidly between 2006 and 2009. The bla
OXA-51-like and ISAba1-associated bla
OXA-23 genes were prevalent in the imipenem-resistant A. baumannii isolates. However, the bla
OXA-58-like gene was found in only one isolate and no metallo-β-lactamase genes were detected. The representative multidrug-resistant A. baumannii isolates were identified as one cluster by rep-PCR fingerprinting and belonged to the clonal complex 92 (CC92) according to MLST. These findings indicate a situation of increasing resistance and wide distribution of class D β-lactamase genes, especially the acquired ISAba1-associated bla
OXA-23 gene, in A. baumannii isolates in the ICU of West China Hospital, probably caused by expansion of the CC92 clone.
Testing probiotic strain Escherichia coli Nissle 1917 (Mutaflor) for its ability to reduce carriage of multidrug-resistant E. coli by elderly residents in long-term care facilities
Authors: Tannock Gerald W. , Tiong Ing Soo , Priest Patricia , Munro Karen , Taylor Corinda , Richardson Alice , Schultz Michael
Published: December 2010

A high carriage rate of multidrug-resistant Escherichia coli (MDREC) was observed in elderly residents in long-term care facilities. A double-blinded, placebo-controlled trial was carried out to determine whether the probiotic product E. coli strain Nissle 1917 (Mutaflor) would compete with MDREC in the bowel and thereby reduce the prevalence of the multiresistant bacteria in faeces and urine. Sixty-nine patients excreting norfloxacin-resistant E. coli were randomized to probiotic or placebo groups and administered capsules twice daily. The daily dose of probiotic was 5×109–5×1010 bacteria. Faecal and urine samples were cultured at baseline and during and after the treatment period. A reduction in baseline carriage was not influenced by probiotic administration. The probiotic strain was detected in faecal specimens collected during the treatment period of only two out of 12 probiotic group subjects that were tested. Genotyping of norfloxacin-resistant E. coli isolates showed that 32 strains were prevalent among the patients. Thus, E. coli Nissle 1917 does not have the capacity to compete effectively with MDREC in the bowel of elderly patients.
Successful treatment of meticillin-resistant Staphylococcus aureus bacteraemia in a neonate using daptomycin
Authors: Hussain Abid , Kairamkonda Venkatesh , Jenkins David Richard
Published: December 2010

Daptomycin is licensed for the management of Staphylococcus aureus infections in adults, including those caused by meticillin-resistant S. aureus (MRSA). Few data exist on paediatric use or dose guidance in neonates. We report the case of a neonate with MRSA bacteraemia successfully managed with daptomycin. Dose requirements were substantially higher than those recommended for adults.
Biochemical and immunological characterization of a cpn60.1 knockout mutant of Mycobacterium bovis BCG
Authors: Wang Xiao-Ming , Lu Changlong , Soetaert Karine , S'Heeren Catherine , Peirs Priska , Lanéelle Marie-Antoinette , Lefèvre Philippe , Bifani Pablo , Content Jean , Daffé Mamadou , Huygen Kris , De Bruyn Jacqueline , Wattiez Ruddy
Published: December 2010

Pathogenic mycobacteria possess two homologous chaperones encoded by cpn60.1 and cpn60.2. Cpn60.2 is essential for survival, providing the basic chaperone function, while Cpn60.1 is not. In the present study, we show that inactivation of the Mycobacterium bovis BCG cpn60.1 (Mb3451c) gene does not significantly affect bacterial growth in 7H9 broth, but that this knockout mutant (Δcpn60.1) forms smaller colonies on solid 7H11 medium than the parental and complemented strains. When growing on Sauton medium, the Δcpn60.1 mutant exhibits a thinner surface pellicle and is associated with higher culture filtrate protein content and, coincidentally, with less protein in its outermost cell envelope in comparison with the parental and complemented strains. Interestingly, in this culture condition, the Δcpn60.1 mutant is devoid of phthiocerol dimycocerosates, and its mycolates are two carbon atoms longer than those of the wild-type, a phenotype that is fully reversed by complementation. In addition, Δcpn60.1 bacteria are more sensitive to stress induced by H2O2 but not by SDS, high temperature or acidic pH. Taken together, these data indicate that the cell wall of the Δcpn60.1 mutant is impaired. Analysis by 2D gel electrophoresis and MS reveals the upregulation of a few proteins such as FadA2 and isocitrate lyase in the cell extract of the mutant, whereas more profound differences are found in the composition of the mycobacterial culture filtrate, e.g. the well-known Hsp65 chaperonin Cpn60.2 is particularly abundant and increases about 200-fold in the filtrate of the Δcpn60.1 mutant. In mice, the Δcpn60.1 mutant is less persistent in lungs and, to a lesser extent, in spleen, but it induces a comparable mycobacteria-specific gamma interferon production and protection against Mycobacterium tuberculosis H37Rv challenge as do the parental and complemented BCG strains. Thus, by inactivating the cpn60.1 gene in M. bovis BCG we show that Cpn60.1 is necessary for the integrity of the bacterial cell wall, is involved in resistance to H2O2-induced stress but is not essential for its vaccine potential.
Plasma biomarker discovery and validation for colorectal cancer by quantitative shotgun mass spectrometry and protein microarray
Authors: Murakoshi Yusuke , Honda Kazufumi , Sasazuki Shizuka , Ono Masaya , Negishi Ayako , Matsubara Junichi , Sakuma Tomohiro , Kuwabara Hideya , Nakamori Shoji , Sata Naohiro , Nagai Hideo , Ioka Tatsuya , Okusaka Takuji , Kosuge Tomoo , Shimahara Masashi , Yasunami Yohichi , Ino Yoshinori , Tsuchida Akihiko , Aoki Tatsuya , Tsugane Shoichiro , Yamada Tesshi
Published: December 2010

The development of a new plasma biomarker for early detection would be necessary to improve the overall outcome of colorectal cancer. Here we report the identification and validation of the ninth component of complement (C9) as a novel plasma biomarker for colorectal cancer by cutting‐edge proteomic technologies. Plasma proteins were enzymatically digested into a large array of peptides, and the relative quantity of a total of 94 803 peptide peaks was compared between 31 colorectal cancer patients and 59 age/sex‐matched healthy controls using 2D image‐converted analysis of liquid chromatography and mass spectrometry. The selected biomarker candidates were validated in 345 subjects (115 colorectal cancer patients and 230 age/sex‐matched healthy controls) using high‐density reverse‐phase protein microarrays. Plasma levels of Apo AI and C9 in colorectal cancer patients significantly differed from healthy controls with P values of 7.94 × 10−4 and 1.43 × 10−12 (Student’s t‐test), respectively. In particular, C9 was elevated in patients with colorectal cancer, including those with stage‐I and ‐II diseases (P = 3.01 × 10−3 and P = 1.13 × 10−5, respectively). Although the significance of the present study must be validated in an independent clinical study, the increment of plasma C9 may be applicable to the early detection of colorectal cancer. (Cancer Sci 2011; 102: 630–638)
Microbial biomass carbon and methane oxidation influenced by rice cultivars and elevated CO2 in a Japanese paddy soil
Authors: Inubushi K. , Cheng W. , Mizuno T. , Lou Y. , Hasegawa T. , Sakai H. , Kobayashi K.
Published: December 2010

Microbial biomass carbon (C) and methane oxidation activity influenced by rice cultivars and elevated atmospheric CO2 were investigated in a microcosm experiment in two controlled‐environment chambers with CO2 concentrations at 370 µl l−1 (ambient) and 570 µl l−1 (elevated). Four rice cultivars were grown in sandy paddy soil in this experiment; these were IR65598, IR72, Dular and Koshihikari. Soil microbial biomass C under elevated CO2 was significantly larger (by 18.9–25.2%) than that under ambient CO2, and varied with the cultivars in the sequence IR72 > Dular > IR65598 > Koshihikari. Methane oxidation activity in the soil also differed among the cultivars, in the sequence IR72 > Dular > Koshihikari > IR65598, but was larger under elevated CO2 than under ambient CO2 only with IR72. Methane oxidation activity was positively correlated with microbial biomass C among four cultivars under two CO2 conditions. This study indicated that microbial biomass C in paddy soil varied among the rice varieties examined, but was increased significantly by elevated CO2 and correlated with methane oxidation, which may in turn influence methane emission to the atmosphere.
Baldness, acne and testicular germ cell tumours
Authors: Trabert B. , Sigurdson A. J. , Sweeney A. M. , Amato R. J. , Strom S. S. , McGlynn K. A.
Published: December 2010

Androgen levels during critical periods of testicular development may be involved in the aetiology of testicular germ cell tumours (TGCT). We evaluated the roles of adolescent and early adult life correlates of androgen exposure and TGCT in a hospital‐based case–control study. TGCT cases (n = 187) and controls (n = 148), matched on age, race and state of residence, participated in the study. Unconditional logistic regression was used to estimate associations between TGCT and male pattern baldness, severe acne, markers of puberty onset and body size. Cases were significantly less likely to report hair loss than controls [odds ratio (OR): 0.6; 95% confidence interval (CI): 0.4, 1.0]. Amount of hair loss, increasing age at onset and increasing rate of loss were all inversely associated with TGCT (rate of hair loss: p‐trend = 0.03; age at onset: p‐trend = 0.03; amount of hair loss: p‐trend = 0.01). History of severe acne was inversely associated with TGCT (OR: 0.5; 95% CI: 0.3, 0.9) and height was positively associated with TGCT (p‐trend = 0.02). Increased endogenous androgen levels during puberty and early adulthood may be associated with a decreased risk of TGCT. Additional studies of endogenous hormone levels during puberty and early adult life are warranted, especially studies evaluating the role of androgen synthesis, metabolism and uptake.
Osteoporosis in people with intellectual disabilities: a review and a brief study of risk factors for osteoporosis in a community sample of people with intellectual disabilities
Authors: Srikanth R. , Cassidy G. , Joiner C. , Teeluckdharry S.
Published: December 2010

Background The population of people with intellectual disabilities (ID) is increasing and their health needs impact on primary and secondary healthcare specialities. One important aspect of their physical health is bone health as people with ID have increased risk factors associated with osteoporosis. It has been identified that this population has an increased prevalence of low bone mineral density (BMD), osteoporosis and osteopenia. The main contributory factors for low BMD are age, use of antiepileptics, immobility and diagnosis of Down's syndrome.

Methods A literature search of electronic databases was undertaken. Studies that included people with ID were reviewed for the prevalence of osteoporosis and osteopenia. A cross‐sectional survey was conducted in a community sample (n = 149) to screen for risk factors for osteoporosis.

Results The majority of studies identified increased prevalence of osteoporosis and osteopenia with associated low BMD. In most studies individuals with ID presented with more than two risk factors. In our survey, we identified an increased prevalence of risk factors associated with osteoporosis, namely use of antiepileptics (64%), immobility (23%), history of falls (20%) and fractures (11%). We found that 54% of our sample fulfilled the criteria for screening. Of those who went on to have scans, 55% had osteoporosis and 33% had osteopenia.

Conclusion We conclude that we should be screening for the risk factors associated with low BMD in adults with ID. If these are present further investigations should take place and those found to have osteoporosis and osteopenia should have treatment at an early stage to prevent morbidity and improve their quality of life.
Low mood and challenging behaviour in people with severe and profound intellectual disabilities
Authors: Hayes S. , McGuire B. , O'Neill M. , Oliver C. , Morrison T.
Published: December 2010

Background  We investigated the relationship between low mood and challenging behaviour in people in the severe and profound range of intellectual disability, while controlling for the presence of potentially confounding variables such as diagnosis of autism, physical and sensory problems and ill health.

Methods  The key workers of 52 people with severe and profound intellectual disability completed measures of depression, communication, challenging behaviour and provided information on relevant demographic and health variables.

Results  Using the Mood, Interest and Pleasure Questionnaire for classification of mood, a significant difference was found between a ‘low mood’ and ‘normothymic’ group in the reported occurrence of challenging behaviour. This difference remained even when confounding variables such as the presence of autism, health and sensory difficulties were controlled. The frequency and severity of challenging behaviour was predicted by measures indicating the presence of low mood.

Conclusion  People with severe and profound show clear and measurable signs of low mood, and in this relatively small sample of institutionalised individuals, low mood was associated with challenging behaviour.