The reconstruction of invasion histories with genomic data in light of differing levels of anthropogenic transport.

Unravelling the history of range shifts is key for understanding past, current and future species distributions. Anthropogenic transport of species alters natural dispersal patterns and directly affects population connectivity. Studies have suggested that high levels of anthropogenic transport homogenize patterns of genetic differentiation and blur colonization pathways. However, empirical evidence of these effects remains elusive. We compared two range-shifting species (Microcosmus squamiger and Ciona robusta) to examine how anthropogenic transport affects our ability to reconstruct colonization pathways using genomic data. We first investigated shipping networks from the 18th century onwards, cross-referencing these with regions where the species have records to infer how each species has potentially been affected by different levels of anthropogenic transport. We then genotyped thousands of single-nucleotide polymorphisms from 280 M. squamiger and 190 C. robusta individuals collected across their extensive species' ranges and reconstructed colonization pathways. Differing levels of anthropogenic transport did not preclude the elucidation of population structure, though specific inferences of colonization pathways were difficult to discern in some of the considered scenario sets. We conclude that genomic data in combination with information of underlying introduction drivers provide key insights into the historic spread of range-shifting species. This article is part of the theme issue 'Species' ranges in the face of changing environments (part I)'.

Storied Lessons: Learning from Anger in Childhood by Narrating.

We evaluated whether narrating anger-provoking events promoted learning from those events, as compared with other responses to anger, and whether the effectiveness of narrative depended on age. In addition, we tested relations between anger-reduction and learning and in a subset of participants, between narrative quality and learning. 248 youth (8 to 17 years old) recalled an anger-provoking experience, and were randomly assigned to one of four activities: recalling the event a second time, narrating the event, and distraction (via video game play or conversation). Youth then recalled the event one last time, and rated the extent to which they had learned from that event. Younger children reported more learning when they had narrated their experience. Older youth reported more learning when they had narrated the event more frequently prior to participation. Stronger reductions in anger following regulation were associated with greater self-reported learning. Finally, more elaborative and less resolved narratives were associated with greater self-reported learning.

Overview of HOMEChem: House Observations of Microbial and Environmental Chemistry.

The House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO2, NOx, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated the submicron mass, and, while variable between meals and throughout the cooking process, was dominated by components of hydrocarbon character and low oxygen content, similar to cooking oil. Air exchange in the house ensured that cooking particles were present for only short periods. During unoccupied background intervals, particle concentrations were lower indoors than outdoors. The cooling coils of the house ventilation system induced cyclic changes in water soluble gases. Even during unoccupied periods, concentrations of many organic trace gases were higher indoors than outdoors, consistent with housing materials being potential sources of these compounds to the outdoor environment. Organic material accumulated on indoor surfaces, and exhibited chemical signatures similar to indoor organic aerosol.

A novel detection method of cleaved plasma high-molecular-weight kininogen reveals its correlation with Alzheimer's pathology and cognitive impairment.

INTRODUCTION: Accumulation of ß-amyloid is a pathological hallmark of Alzheimer's disease (AD). ß-Amyloid activates the plasma contact system leading to kallikrein-mediated cleavage of intact high-molecular-weight kininogen (HKi) to cleaved high-molecular-weight kininogen (HKc). Increased HKi cleavage is observed in plasma of AD patients and mouse models by Western blot. For potential diagnostic purposes, a more quantitative method that can measure HKc levels in plasma with high sensitivity and specificity is needed. METHODS: HKi/c, HKi, and HKc monoclonal antibodies were screened from hybridomas using direct ELISA with a fluorescent substrate. RESULTS: We generated monoclonal antibodies recognizing HKi or HKc specifically and developed sandwich ELISAs that can quantitatively detect HKi and HKc levels in human. These new assays show that decreased HKi and increased HKc levels in AD plasma correlate with dementia and neuritic plaque scores. DISCUSSION: High levels of plasma HKc could be used as an innovative biomarker for AD.

Oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA), a hidden resistant mechanism among clinically significant isolates in the Wessex region/UK.

PURPOSE: Methicillin-resistant Staphylococcus aureus (MRSA) is defined as S. aureus genetically having the mecA or mecC genes or phenotypically showing minimum inhibitory concentration (MIC) of oxacillin higher than 2 mg/L. However, recently, cefoxitin/oxacillin-susceptible mecA-positive S. aureus (OS-MRSA) has been reported worldwide. Little is known about the prevalence and virulence of these strains among clinically significant isolates in the UK. The aims were to (1) investigate the prevalence of OS-MRSA in seven major hospitals in the Wessex region/UK from a cohort of 500 clinically significant phenotypically identified MSSA isolates, (2) genetically characterise OS-MRSA strains by pulsed-field gel electrophoresis (PFGE) and compare these to common UK epidemic strains; and (3) to determine Panton-Valentine leukocidin (PVL; lukFS) gene carriage rates among these isolates. RESULTS: OS-MRSA was found in six isolates (1.2 %) of phenotypically identified and reported MSSA isolates by conventional methods. PFGE showed OS-MRSA strains to be genetically diverse and distinct from the common UK epidemic strains EMRSA-15 and EMRSA-16. None of these OS-MRSA stains carried the genes encoding PVL; however, overall positivity rate for PVL was 4.4 %, much higher than the nationally reported rates of 2 % in the UK. CONCLUSION: There are still many unknowns regarding phenotypic and/or genetic characterization of the emerging OS-MRSA isolates in the UK and worldwide. Data regarding their epidemiology and optimal therapy for infection are limited and need further investigation not only in the UK, but also worldwide, as it is likely to have an impact on the empirical treatment of S. aureus infections.

Antibiotic stewardship and early discharge from hospital: impact of a structured approach to antimicrobial management.

OBJECTIVES: To assess the impact of an infection team review of patients receiving antibiotics in six hospitals across the UK and to establish the suitability of these patients for continued care in the community. METHODS: An evaluation audit tool was used to assess all patients on antibiotic treatment on acute wards on a given day. Clinical and antibiotic use data were collected by an infection team (doctor, nurse and antibiotic pharmacist). Assessments were made of the requirement for continuing antibiotic treatment, route and duration [including intravenous (iv)/oral switch] and of the suitability of the patients for discharge from hospital and their requirement for community support. RESULTS: Of 1356 patients reviewed, 429 (32%) were on systemic antibiotics, comprising 165 (38%) on iv ±â€Šoral antibiotics and 264 (62%) on oral antibiotics alone. Ninety-nine (23%) patients (including 26 on iv antibiotics) had their antibiotics stopped immediately on clinical grounds. The other 330 (77%) patients (including 139 on iv antibiotics) needed to continue antibiotics, although 47 (34%) could be switched to oral. Eighty-nine (21%) patients were considered eligible for discharge, comprising 10 who would have required outpatient parenteral antibiotic therapy (OPAT), 55 who were suitable for oral outpatient treatment and 24 who had their antibiotics stopped. CONCLUSIONS: Infection team review had a significant impact on antimicrobial use, facilitating iv to oral switch and a reduction in the volume of antibiotic use, possibly reducing the risk of healthcare-associated complications and infections. It identified many patients who could potentially have been managed in the community with appropriate resources, saving 481 bed-days. The health economics are reported in a companion paper.

Reduction in antibiotic use through procalcitonin testing in patients in the medical admission unit or intensive care unit with suspicion of infection.

We report an evaluation of the utility of serum procalcitonin (PCT) measurement as an additional diagnostic tool to support initiating or withholding antibiotics in clinical situations where there is a clinical suspicion of infection but the diagnosis is uncertain. During a six-month period, 99 patients on the medical admission unit (MAU) with suspected infection, and 42 patients on the intensive care unit (ICU) with clinical signs or physiological parameters suggesting possible new infection, had serum PCT concentration measured with the result available within 90min of the request. The test was initiated by the microbiology/infection team during clinical consultations to support the antibiotic decision. On the basis of low PCT values, antibiotics were withheld in MAU on 52 occasions and in ICU on 42 occasions. Patients were followed up prospectively for a week. There was neither progression of bacterial infection requiring antibiotics, nor complications or infection-related mortality in any patients who were denied antibiotics on either MAU or ICU. Without the PCT value it is likely that all of these patients would have received empirical antibiotics. Reduction in unnecessary antibiotic usage was made without any adverse effects on these patients and there was a clear reduction in antibiotic prescribing with cost reduction implications. PCT has the potential to become a valuable tool in antibiotic management.

The management of acute diarrhoea in a healthy adult population deploying on military operations.

Acute diarrhoea is consistently the number one presentation to secondary care facilities on U.K. military operational deployments. It can result in potentially life threatening consequences as seen on Operation Herrick in 2002, where a Norwalk-like virus caused 3 cases o f meningo-encephalitis. Due to t he circumstances of communalaccommodation, ablutions and dining facilities, even mild cases are admitted at role 2, and personnel are not discharged until fully recovered in order to prevent potential outbreaks. This literature review examines the management of acute diarrhoea in healthy adults relating to UK military operations, and presents a management algorithm suitable for any theatre. The importance of the initial assessment is highlighted and allows the severity of the condition to be assessed using three key parameters. We recommend the selective use of stool culturing for severe cases and outbreaks. The use of oral re-hydration solutions vs. intravenous fluids, and the indication for the safe use of anti motility agents and antibiotics for diarrhoea are discussed. Where pathogens are yielded local sensitivities should guide the choice of treatment. Salmonella spp and Shiga toxin-producing E.coli (STEC) should receive supportive care only.

Dose- and time-dependent changes in gene expression in human glioma cells after low radiation doses.

We have used DNA microarrays to identify changes in gene expression in cells of the radioresistant human glioma cell lines T98G and U373 after low radiation doses (0.2-2 Gy). Using Bayesian linear models, we have identified a set of genes that respond to low doses of radiation; furthermore, a hypothesis-driven approach to data analysis has allowed us to identify groups of genes with defined non-linear dose responses. Specifically, one of the cell lines we have examined (T98G) shows increased radiosensitivity at low doses (low-dose hyper-radiosensitivity, HRS); thus we have also assessed sets of genes whose dose response mirrors this survival pattern. We have also investigated a time course for induction of genes over the period when the DNA damage response is expected to occur. We have validated these data using quantitative PCR and also compared genes up-regulated in array data to genes present in the polysomal RNA fraction after irradiation. Several of the radioresponsive genes that we describe code for proteins that may have an impact on the outcome of irradiation in these cells, including RAS homologues and kinases involved in checkpoint signaling, so understanding their differential regulation may suggest new ways of altering radioresistance. From a clinical perspective these data may also suggest novel targets that are specifically up-regulated in gliomas during radiotherapy treatments.

The impact of surgically induced ischaemia on protein levels in patients undergoing rectal cancer surgery.

The goal of targeted therapy has driven a search for markers of prognosis and response to adjuvant therapy. The surgical resection of a solid tumour induces tissue ischaemia and acidosis, both potent mediators of gene expression. This study investigated the impact of colorectal cancer (CRC) surgery on prognostic and predictive marker levels. Tumour expression of thymidylate synthase, thymidine phosphorylase, cyclin A, vascular endothelial growth factor (VEGF), carbonic anhydrase-9, hypoxia inducible factor-1alpha, and glucose transporter-1 (GLUT-1) proteins was determined before and after rectal cancer surgery. Spectral imaging of tissue sections stained by immunohistochemistry provided quantitative data. Surgery altered thymidylate synthase protein expression (P=0.02), and this correlated with the change in the proliferation marker cyclin A. The expression of hypoxia inducible factor-1alpha, VEGF, and GLUT-1 proteins was also different following surgery. Colorectal cancer surgery significantly impacts on intratumoral gene expression, suggesting archival specimens may not accurately reflect in situ marker levels. Although rectal cancer was the studied model, the results may be applicable to any solid tumour undergoing extirpation in which molecular markers have been proposed to guide patient therapy.

The effect of surgically induced ischaemia on gene expression in a colorectal cancer xenograft model.

Delays in tissue fixation following tumour vascular clamping and extirpation may adversely affect subsequent protein and mRNA analysis. This study investigated the effect of surgically induced ischaemia in a xenograft model of a colorectal cancer on the expression of a range of prognostic, predictive, and hypoxic markers, with a particular emphasis on thymidylate synthase. Vascular occlusion of human tumour xenografts by D-shaped metal clamps permitted defined periods of tumour ischaemia. Alterations in protein expression were measured by immunohistochemistry and spectral imaging, and changes in mRNA were measured by reverse transcriptase-polymerase chain reaction. Thymidylate synthase expression decreased following vascular occlusion, and this correlated with cyclin A expression. A similar reduction in dihydropyrimidine dehydrogenase was also seen. There were significant changes in the expression of several hypoxic markers, with carbonic anhydrase-9 showing the greatest response. Gene transcriptional levels were also noted to change following tumour clamping. In this xenograft model, surgically induced tumour ischaemia considerably altered the gene expression profiles of several prognostic and hypoxic markers, suggesting that the degree of tumour ischaemia should be minimised prior to tissue fixation.

DNA damage responses at low radiation doses.

Increased cell killing after exposure to low acute doses of X rays (0-0.5 Gy) has been demonstrated in cells of a number of human tumor cell lines. The mechanisms underlying this effect have been assumed to be related to a threshold dose above which DNA repair efficiency or fidelity increases. We have used cells of two radioresistant human tumor cell lines, one that shows increased sensitivity to low radiation doses (T98G) and one that does not (U373), to investigate the DNA damage response at low doses in detail and to establish whether there is a discontinuous dose response or threshold in activation of any important mediators of this response. In the two cell lines studied, we found a sensitive, linear dose response in early signaling and transduction pathways between doses of 0.1 and 2 Gy with no evidence of a threshold dose. We demonstrate that ATM-dependent signaling events to downstream targets including TP53, CHK1 and CHK2 occur after doses as low as 0.2 Gy and that these events promote an effective damage response. Using chemical inhibition of specific DNA repair enzymes, we show that inhibition of DNA-PK-dependent end joining has relatively little effect at low (<1 Gy) doses in hyper-radiosensitive cells and that at these doses the influence of RAD51-mediated repair events may increase, based on high levels of RAD51/BRCA2 repair foci. These data do not support a threshold model for activation of DNA repair in hyper-radiosensitive cells but do suggest that the balance of repair enzyme activity may change at low doses.

Osteogenic differentiation of mouse embryonic stem cells: differential gene expression analysis by cDNA microarray and purification of osteoblasts by cadherin-11 magnetically activated cell sorting.

We have previously shown osteogenic differentiation of mouse embryonic stem (ES) cells and temporal enrichment with osteoblastic cells, by stimulation with serum-containing culture medium supplemented with beta-glycerophosphate, ascorbate, and dexamethasone. In our present study we have used similar culture conditions to further investigate osteogenic differentiation of mouse ES cells. Using reverse transcription-polymerase chain reaction (RT-PCR) we demonstrated the expression of genes associated with osteoblast differentiation including the bone matrix protein osteocalcin and the transcription factor Cbfa-1/runx2. Furthermore, results of cDNA microarray analysis, and subsequent RT-PCR analysis of differentiating ES cells after exposure to osteogenic stimuli, revealed a combination of upregulation of genes involved in osteoblast differentiation including osteopontin, HSP-47, and IGF-II coupled with downregulation of genes involved in differentiation of other phenotypes such as the neuroectoderm factor Stra-13. Finally, we have applied magnetically activated cell-sorting methods to ES cell cultures treated with osteogenic stimuli and, using an antibody to cadherin-11, have purified a subpopulation of cells with osteoblastic characteristics.

Differentiation of osteoblasts and in vitro bone formation from murine embryonic stem cells.

Pluripotent embryonic stem (ES) cells have the potential to differentiate to all fetal and adult cell types and might represent a useful cell source for tissue engineering and repair. Here we show that differentiation of ES cells toward the osteoblast lineage can be enhanced by supplementing serum-containing media with ascorbic acid, beta-glycerophosphate, and/or dexamethasone/retinoic acid or by co-culture with fetal murine osteoblasts. ES cell differentiation into osteoblasts was characterized by the formation of discrete mineralized bone nodules that consisted of 50-100 cells within an extracellular matrix of collagen-1 and osteocalcin. Dexamethasone in combination with ascorbic acid and beta-glycerophosphate induced the greatest number of bone nodules and was dependent on time of stimulation with a sevenfold increase when added to ES cultures after, but not before, 14 days. Co-culture with fetal osteoblasts also provided a potent stimulus for osteogenic differentiation inducing a fivefold increase in nodule number relative to ES cells cultured alone. These data demonstrate the application of a quantitative assay for the derivation of osteoblast lineage progenitors from pluripotent ES cells. This could be applied to obtain purified osteoblasts to analyze mechanisms of osteogenesis and for use of ES cells in skeletal tissue repair.

Supracostal percutaneous nephrolithotomy for upper pole caliceal calculi.

The incidence of upper pole calculi is 15% of all caliceal calculi. The management of such calculi has been simplified since the advent of extracorporeal shockwave lithotripsy (SWL). In our experience, however, there is a subset of upper pole caliceal calculi wherein certain features can render SWL less than adequate treatment, namely diameter >1.5 cm, narrowing of the caliceal infundibulum, either singly or combined, and morbid obesity. In such instances, percutaneous nephrolithotomy (PCNL) is indicated. Percutaneous access to an upper pole calix can be difficult by a subcostal track. The supracostal 12th rib approach provides direct and efficient access to an upper pole calix and is ideally suited for upper pole calculi. Twenty-one patients with large or complex upper pole calculi were treated by supracostal PCNL. The maximum diameter of the calculi ranged from 7 to 40 mm. Eight were branched (staghorn). There was one horseshoe kidney, and calculi were bilaterally represented in another patient. Two patients were morbidly obese. All procedures were performed in one stage under general anesthesia. Following cystoscopy and ureteral catheterization, the upper pole calix was accessed directly with the aid of C-arm fluoroscopy and retrograde ureteral contrast injection. The percutaneous tract was dilated to a maximum of 26 F, a working sheath was inserted, and the calculi were extracted after ultrasonic or pneumatic fragmentation. One patient required secondary SWL for residual fragments. There were no intrathoracic complications, and blood loss was minimal. Large or complex upper pole caliceal calculi, particularly in the morbidly obese, can be treated effectively by PCNL using supracostal percutaneous access.

Bulimia nervosa, restrained, and unrestrained eaters: a comparison of non-binge eating behavior.

OBJECTIVE: This study investigated non-binge eating behavior in bulimia nervosa, restrained and unrestrained eaters. METHOD: Nine females with bulimia nervosa, 12 female restrained eaters, and 13 female unrestrained eaters were administered the Eating Disorder Inventory-2 (EDI-2), the Body Shape Questionnaire, the Beck Depression Inventory, the Rosenberg Self-Esteem Scale, and the Revised Restraint Scale (RRS). All subjects were videotaped during a midday meal and their eating behavior was subsequently rated using the Eating Behaviour Rating Scale (EBRS). RESULTS: EBRS ratings were higher for bulimic than for unrestrained subjects. Restrained subjects' ratings did not differ from those of either bulimic or unrestrained subjects. EBRS scores were positively correlated with RRS and EDI-2 total scores. CONCLUSIONS: Bulimic subjects display aberrant eating behavior, and the extent to which subjects engage in maladaptive eating behavior is related to the degree of eating pathology. These results support the utility of the EBRS as a useful index of eating behaviors in clinical and nonclinical populations.

Screening for unhealthy lifestyle factors in the workplace.

OBJECTIVE: To examine (1) the prevalence of four lifestyle behaviours among Australia Post employees and (2) employees' perceptions of the role of the workplace in promotion of lifestyle change. DESIGN: A cross-sectional survey using a self-administered questionnaire involved 688 employees working in Australia Post throughout metropolitan Sydney. MAIN OUTCOME MEASURES: Prevalence related to age and sex of alcohol consumption, cigarette smoking, inadequate exercise, perception of excessive weight. RESULTS: 36% of men and 11% of women reported drinking alcohol at levels considered hazardous or harmful; 33% of men and 25% of women reported smoking; 51% of men and 62% of women thought they were overweight; 30% of men and 39% of women did not exercise regularly. Younger respondents were more likely to report drinking hazardously or harmfully, were smokers and had multiple risk factors. A majority of respondents thought that their employer should be interested in employee's lifestyle issues, particularly excessive drinking (63%). However, few considered seeking advice from the workplace regarding smoking (16%), weight (25%) and excessive alcohol consumption (12%). CONCLUSIONS: These results show that many of Australia Post employees have unhealthy lifestyle behaviours. While employees perceive that the workplace has an important role in promoting healthy lifestyles among staff, few are presently willing to seek advice from the workplace regarding these issues. Promotion of healthy lifestyles in Australian workplaces is a potentially important public health advance that could reduce the incidence of diseases associated with high-risk lifestyle behaviours.

Rare microsatellite polymorphisms in the DNA repair genes XRCC1, XRCC3 and XRCC5 associated with cancer in patients of varying radiosensitivity.

DNA repair defects might contribute both to cancer progression and to the extreme reactions to radiotherapy observed in approximately 5% of patients. Polymorphic microsatellites in three DNA repair genes, XRCC1, XRCC3 and XRCC5, were analyzed for possible linkage to cancer status or clinical radiosensitivity. XRCC1, 3 and 5 proteins are involved in single-strand DNA break rejoining, recombinational repair, and double-strand DNA break rejoining respectively. Mendelianly inherited microsatellite polymorphisms in these genes were analyzed in three groups: volunteers with no cancer history; radiosensitive cancer patients; cancer patients with acceptable reactions to radiotherapy. Rare heterozygous alterations in all three gene regions were found solely in the cancer subpopulation. Association testing between these rare polymorphisms and cancer status revealed a significant association for XRCC1 (P = 0.005), and XRCC3 (P = 0.004). There was also an association between these polymorphisms and clinical radiosensitivity for XRCC1 (P = 0.03), and XRCC3 (P = 0.005).