bluuebunny/crossref_metadata_2025 huggingface dataset:
The behavioural ecology and population dynamics of a cryptic ground‐dwelling mammal in an urban Australian landscape
Authors: FITZGIBBON SEAN I. , WILSON ROBBIE S. , GOLDIZEN ANNE W.
Published: December 2010

Urbanization results in widespread habitat loss and fragmentation and generally has a negative impact upon native wildlife, in particular ground‐dwelling mammals. The northern brown bandicoot (Isoodon macrourus; Marsupialia: Peramelidae) is one of relatively few native Australian ground‐dwelling mammals that is able to survive within urbanized landscapes. As a consequence of extensive clearing and urban development within the city of Brisbane, bandicoots are now restricted to the mostly small (<10 ha) bushland fragments scattered across the city landscape. Our study examined the behavioural ecology of northern brown bandicoots within habitat fragments located on a major creek‐line, using mark‐recapture population monitoring and radio telemetry. Bandicoots at monitored sites were found to occur at high densities (typically one individual ha−1), although one‐third of the populations were transient. Radio tracking revealed that bandicoots had relatively small home ranges (mean 1.5 ± 0.2 ha) comprised largely of bushland/grassland with dense, often weed‐infested ground cover. Bandicoots sheltered by day in these densely covered areas and also spent most time foraging there at night, although they occasionally ventured small distances to forage in adjacent maintained parklands and residential lawns. We suggest that introduced tall grasses and other weeds contribute to high habitat quality within riparian habitat fragments and facilitate the persistence of high density populations, comprised of individuals with small home ranges. The generalized dietary and habitat requirements of northern brown bandicoots, as well as a high reproductive output, undoubtedly facilitate the survival of the species in urban habitat fragments. Further research is required on other native mammal species in urbanized landscapes to gain a greater understanding of how best to conserve wildlife in these heavily modified environments.
Mislocalization of near‐threshold tactile stimuli in humans: a central or peripheral phenomenon?
Authors: Braun Christoph , Eisele Effi , Wühle Anja , Stüttgen Maik C. , Schwarz Cornelius , Demarchi Gianpaolo
Published: December 2010

Principles of brain function can be disclosed by studying their limits during performance. Tactile stimuli with near‐threshold intensities have been used to assess features of somatosensory processing. When stimulating fingers of one hand using near‐threshold intensities, localization errors are observed that deviate significantly from responses obtained by guessing – incorrectly located stimuli are attributed more often to fingers neighbouring the stimulated one than to more distant fingers. Two hypotheses to explain the findings are proposed. The ‘central hypothesis’ posits that the degree of overlap of cortical tactile representations depends on stimulus intensity, with representations less separated for near‐threshold stimuli than for suprathreshold stimuli. The ‘peripheral hypothesis’ assumes that systematic mislocalizations are due to activation of different sets of skin receptors with specific thresholds. The present experiments were designed to decide between the two hypotheses. Taking advantage of the frequency tuning of somatosensory receptors, their contribution to systematic misclocalizations was studied. In the first experiment, mislocalization profiles were investigated using vibratory stimuli with frequencies of 10, 20 and 100 Hz. Unambiguous mislocalization effects were only obtained for the 10‐Hz stimulation, precluding the involvement of Pacinian corpuscles in systematic mislocalization. In the second experiment, Pacinian corpuscles were functionally eliminated by applying a constant 100‐Hz vibratory masking stimulus together with near‐threshold pulses. Despite masking, systematic mislocation patterns were observed rendering the involvement of Pacinian corpuscles unlikely. The results of both experiments are in favor of the ‘central hypothesis’ assuming that the extent of overlap in somatosensory representations is modulated by stimulus intensity.
Enhanced root exudation induces microbial feedbacks to N cycling in a pine forest under long‐term CO2 fumigation
Authors: Phillips Richard P. , Finzi Adrien C. , Bernhardt Emily S.
Published: December 2010

Ecology Letters (2011) 14: 187–194

The degree to which rising atmospheric CO2 will be offset by carbon (C) sequestration in forests depends in part on the capacity of trees and soil microbes to make physiological adjustments that can alleviate resource limitation. Here, we show for the first time that mature trees exposed to CO2 enrichment increase the release of soluble C from roots to soil, and that such increases are coupled to the accelerated turnover of nitrogen (N) pools in the rhizosphere. Over the course of 3 years, we measured in situ rates of root exudation from 420 intact loblolly pine (Pinus taeda L.) roots. Trees fumigated with elevated CO2 (200 p.p.m.v. over background) increased exudation rates (μg C cm−1 root h−1) by 55% during the primary growing season, leading to a 50% annual increase in dissolved organic inputs to fumigated forest soils. These increases in root‐derived C were positively correlated with microbial release of extracellular enzymes involved in breakdown of organic N (R2 = 0.66; P = 0.006) in the rhizosphere, indicating that exudation stimulated microbial activity and accelerated the rate of soil organic matter (SOM) turnover. In support of this conclusion, trees exposed to both elevated CO2 and N fertilization did not increase exudation rates and had reduced enzyme activities in the rhizosphere. Collectively, our results provide field‐based empirical support suggesting that sustained growth responses of forests to elevated CO2 in low fertility soils are maintained by enhanced rates of microbial activity and N cycling fuelled by inputs of root‐derived C. To the extent that increases in exudation also stimulate SOM decomposition, such changes may prevent soil C accumulation in forest ecosystems.
Congruence, non‐homology, and the phylogeny of basal turtles
Authors: Joyce Walter G. , Sterli Juliana
Published: December 2010

Joyce, W.G. and Sterli J. 2010. Congruence, non‐homology, and the phylogeny of basal turtles.–Acta Zoologica (Stockholm)

Modern cladistic analysis is characterized by the assembly of increasingly larger data sets coupled with the use of congruence as the final test of homology. Some critics of this development have recently called for a return to more detailed primary homology analysis while questioning the utility of congruence. This discussion appears to be central to the debate regarding the phylogenetic relationships of basal turtles, as the large data sets developed by us have been criticized recently for utilizing poorly constructed characters and including too many homoplasy‐prone characters. Our analysis of this critique reveals that (1) new information regarding poorly understood taxa has a greater impact on the outcome of turtle phylogenies than the characters under dispute; (2) most current turtle phylogenies differ in taxon sampling, not character sampling, and so it appears illogical to condemn a particular analysis for its character sampling; (3) even evolutionary taxonomists should agree that key characters utilized to resolve basal turtle relationships cannot be thought to be ‘infallible’; (4) whereas various criteria provide positive evidence for homology, only congruence provides positive evidence for non‐homology; and (5) a stalemate between conflicting camps within a congruence frame work is preferable to the ad hoc dismissal of data sets, because authoritative statements are untestable.
The Association of Public Health Observatories (APHO) Diabetes Prevalence Model: estimates of total diabetes prevalence for England, 2010–2030
Authors: Holman N. , Forouhi N. G. , Goyder E. , Wild S. H.
Published: December 2010

Diabet. Med. 28, 575–582 (2011)

Aim  To provide robust estimates of the total prevalence of diabetes (including undiagnosed) in England to support effective planning and delivery of services.

Methods  Age‐ and sex‐specific prevalence of diagnosed and undiagnosed diabetes in people aged 16 years and older [based on HbA1c of 6.5% (48 mmol/mol) or greater] were taken from the Health Survey for England 2006. Data from the Health Survey for England 2004 were used to adjust for ethnic difference in prevalence. A deprivation adjustment refined the geographical distribution of diabetes prevalence. Projected diabetes prevalence was calculated using trends in overweight and obesity prevalence from the Health Surveys for England 2003 to 2008.

Results  In 2010 there were an estimated 3.1 million (7.4%) people aged 16 years and older with diabetes in England. Comparisons between the 2008/2009 Quality and Outcomes Framework data and estimates for 2009 suggest that that 27.1% of the total number of people with diabetes are not included on general practice diabetes registers. The total number of adults with diabetes is projected to rise to 4.6 million or 9.5% by 2030. Approximately half of this increase is attributable to the changing age and ethnic group structure of the population and half is because of the rising prevalence of obesity.

Conclusions  This model estimates that the prevalence of total diabetes (diagnosed and undiagnosed) in England is higher than previously suggested. An ageing population and increasing prevalence of obesity imply that the prevalence of diabetes will continue to rise and health services should be planned accordingly.
Cardiovascular autonomic neuropathy contributes to left ventricular diastolic dysfunction in subjects with Type 2 diabetes and impaired glucose tolerance undergoing coronary angiography
Authors: Dinh W. , Füth R. , Lankisch M. , Bansemir L. , Nickl W. , Scheffold T. , Bufe A. , Krahn T. , Ziegler D.
Published: December 2010

Diabet. Med. 28, 311–318 (2011)

Aims  Left ventricular diastolic dysfunction is considered a precursor of diabetic cardiomyopathy, while diabetic cardiovascular autonomic neuropathy is associated with an increased risk of mortality. This study aimed to evaluate the association between left ventricular diastolic dysfunction and cardiovascular autonomic neuropathy, both diagnosed according to the current guidelines.

Methods  We evaluated 145 patients referred for an elective coronary angiography, 52 of whom had Type 2 diabetes and 48 had impaired glucose tolerance, while 45 subjects had normal glucose tolerance. Cardiovascular autonomic neuropathy was diagnosed using autonomic function tests, while left ventricular diastolic dysfunction was verified by tissue Doppler imaging echocardiography.

Results  Cardiovascular autonomic neuropathy was diagnosed in 15 (28.8%) patients with Type 2 diabetes and in six (12.5%) individuals with impaired glucose tolerance. The rates of left ventricular diastolic dysfunction were 81 and 33% in patients with and without cardiovascular autonomic neuropathy, respectively (P < 0.001). In the cardiovascular autonomic neuropathy group (n = 21), early diastolic relaxation velocity (Em) was significantly reduced (5.4 ± 0.9 vs. 7.3 ± 2.1 cm/s; P < 0.001) and the E/Em ratio was significantly higher (13.6 ± 4.6 vs. 10.3 ± 3.4 cm/s, P < 0.001) as compared with the group without cardiovascular autonomic neuropathy (n = 79). These findings remained significant after adjustment for age, sex, coronary artery disease, hypertension and HbA1c. A severe form of left ventricular diastolic dysfunction was observed in 33 and 15% of patients with and without cardiovascular autonomic neuropathy, respectively (P = 0.001).

Conclusion  Cardiovascular autonomic neuropathy is associated with a higher prevalence and a more severe form of left ventricular diastolic dysfunction in patients with diabetes or impaired glucose tolerance undergoing coronary angiography. Because both cardiovascular autonomic neuropathy and left ventricular diastolic dysfunction are associated with increased cardiovascular morbidity and mortality, screening for patients with left ventricular diastolic dysfunction and cardiovascular autonomic neuropathy with diabetes or impaired glucose tolerance may identify those at high risk.
CULTURE AND GROWTH: SOME EMPIRICAL EVIDENCE
Authors: Chambers Dustin , Hamer Susan
Published: December 2010

Using Hofstede's cultural data set, this paper examines the impact of cultural characteristics on a nation's economic performance. Using a two‐step estimation procedure, we first estimate a panel growth regression and obtain estimates of each nation's fixed effects, which reflect idiosyncratic differences in growth performance. In the second step, we regress the fixed effects on invariant cultural and institutional variables. Our estimation results suggest that individuality and tolerance for uncertainty are the most important cultural factors in explaining nation‐specific growth performance. Furthermore, our findings suggest that political and property rights play a major role in determining idiosyncratic growth.
Technology outsourcing in manufacturing small‐ and medium‐sized firms: another competitive resource?
Authors: O'Regan Nicholas , Kling Gerhard
Published: December 2010

Based on a sample of UK manufacturing small‐ and medium‐sized firms in the engineering and electronics industry, the study identifies firm‐ and industry‐specific factors that stimulate R&D outsourcing and assesses the impact of R&D investment and outsourcing on firms' profitability. The findings indicate that (1) R&D investment fosters profitability, (2) firms with a lower turnover spend less on R&D, (3) current R&D does not explain innovation measured by revenues from new products and patents, (4) smaller firms with lower R&D investment levels tend to outsource R&D and (5) outsourcing is not inferior in terms of product innovation. Hence, outsourcing can enhance profitability – albeit the benefit of outsourcing decreases with firm size. Managers of small firms should consider outsourcing R&D, as this can reduce R&D expenditure and lead to the more effective use of resources as well as achieving a similar degree of product innovation with resultant increases in profitability.
Outsourcing R&D: a review, model, and research agenda
Authors: Hsuan Juliana , Mahnke Volker
Published: December 2010

Outsourcing R&D is an increasingly explored corporate practice. Extant research advanced our initial understanding of its increasing importance and benefits. While the associated literature has blossomed, the enthusiasm of R&D managers is tenured by an increasing realization of the possible downsides, risks, and costs that come with increasing use of external sources of innovation. Here, we suggest that research on outsourcing R&D has to move towards a balanced view on the profitability of such arrangements. To this end, we offer a review of what we know and need to know about outsourcing R&D, suggest a simple, yet integrative model on the relation between outsourcing R&D and performance, and offer a research agenda that is instrumental in guiding companies' process‐management and design strategies when seeking to benefit from the outsourcing of R&D.
Generative and degenerative interactions: positive and negative dynamics of open, user‐centric innovation in technology and engineering consultancies
Authors: Hopkins Michael M. , Tidd Joe , Nightingale Paul , Miller Roger
Published: December 2010

The related concepts of open innovation and user‐centric innovation are currently popular in the literature on technology and innovation management. In this paper, we attempt to address two shortcomings to their practical application. First, the precise mechanisms supporting open and user innovation in different industrial contexts are poorly specified. Second, it is not clear under what circumstances they might become dysfunctional. We identify how the interaction of meso‐ and micro‐level mechanisms contribute to project‐based user‐centric innovation, based on a detailed characterization of the business activities of eight technology and engineering consultancies working across a range of sectors. We develop and illustrate the notion ofgenerative interaction, which describes a series of mechanisms that produce a self‐re‐enforcing ecology, which favours innovation and profitability. At the same time, we observe the opposite dynamics of self‐reinforcingdegenerative interactionlikely to produce a cycle of declining innovation and profitability. In the specific context of project‐based firms, we show that user‐centric, open innovation can affect performance negatively, and we discuss the consequences (positive and negative) of different patterns of interaction with clients.
Bayesian Inference for Contact Networks Given Epidemic Data
Authors: GROENDYKE CHRIS , WELCH DAVID , HUNTER DAVID R.
Published: December 2010

Abstract.  In this article, we estimate the parameters of a simple random network and a stochastic epidemic on that network using data consisting of recovery times of infected hosts. The SEIR epidemic model we fit has exponentially distributed transmission times with Gamma distributed exposed and infectious periods on a network where every edge exists with the same probability, independent of other edges. We employ a Bayesian framework and Markov chain Monte Carlo (MCMC) integration to make estimates of the joint posterior distribution of the model parameters. We discuss the accuracy of the parameter estimates under various prior assumptions and show that it is possible in many scientifically interesting cases to accurately recover the parameters. We demonstrate our approach by studying a measles outbreak in Hagelloch, Germany, in 1861 consisting of 188 affected individuals. We provide an R package to carry out these analyses, which is available publicly on the Comprehensive R Archive Network.
The Move Towards the Knowledge‐based Society: a Gender Approach
Authors: Caprile Maria , Pascual Amparo Serrano
Published: December 2010

There is more to the knowledge‐based society (KBS) than an increasing use of new information and communication technologies (ICTs). It involves a new production paradigm and, therefore, a redefinition of how our societies function. In the political debate a direct linear causality has been established between the move towards the KBS and social cohesion. We discuss this assumption using the concrete example of gender equality. There are three processes at the very core of the paradigmatic change in the production system: new forms of knowledge (demand for ICT skills, but also social competences), a transformation in the type of products in demand (tertiarization of the economy), and new modes of regulation (new forms of work organization and new types of work). We discuss the main conclusions of the prolific debate that has recently taken place concerning the gender impact of these processes and present a statistical analysis of the gender dimension of the KBS resulting from them. This analysis demonstrates that progress in gender equality is not balanced. While it is important when accessing employment, it is much more limited as far as pay and childcare are concerned. Making headway in one of these dimensions of gender equality is not necessarily associated with progress in others. Secondly, this analysis shows that there is not necessarily a direct connection between a high educational level and gender equality. Finally, it shows that the role played by institutional factors is very significant, although it varies depending on the equality dimension considered.
RADICAL FORGIVENESS AND HUMAN JUSTICE
Authors: FIALA ANDREW
Published: December 2010

The most substantial source for thinking about forgiveness is Christian ethics. Some Christians offer forgiveness even for atrocities in the absence of repentance and reparations. The paper critically examines Christian idealism about forgiveness, while looking beyond Christianity toward a humanistic approach that acknowledges the tragic conflict between forgiveness and justice. Christian forgiveness is part of a radical revaluation of values regarding the goods of this world, personal identity, and temporality. Humanistic approaches, as found in Kant and the Greeks, do not embrace this radical revaluation of values. But it remains useful to consider the benefits of forgiveness, even for those who are not willing to commit to such a radical revaluation.
Hip fracture patients’ cognitive state affects family members’ experiences – a diary study of the hip fracture recovery
Authors: Hedman Ann‐Marie Rydholm , Strömberg Lars , Grafström Margareta , Heikkilä Kristiina
Published: December 2010

Scand J Caring Sci; 2011; 25; 451–458
 
Hip fracture patients’ cognitive state affects family members’ experiences – a diary study of the hip fracture recovery

Background:  Many patients with hip fractures suffer from dementia disease, which has shown to affect the outcome of recovery strongly, as well as care and treatment. As most hip fracture patients are discharged home early after surgery, caregiving often falls on family members – spouses, daughters, sons, or even neighbours become informal carers.

Aim:  To explore how hip fracture patients’ cognitive state affect family members’ experiences during the recovery period.

Methods:  Eleven diaries written by family members’ of hip fracture patients were analysed by means of qualitative content analysis.

Findings:  The analysis generated two main categories with four categories. The first main category was; ‘Being a family member of a cognitively impaired patient’ with the categories ‘Dissatisfaction with lack of support’ and ‘Emotional distress due to the patient’s suffering’. The second main category was ‘Being a family member of a cognitively intact patient’ with the categories ‘Satisfaction with a relative’s successful recovery’ and ‘Strain due to their caring responsibilities’. Being a family member of a patient with cognitive impairment and a hip fracture meant being solely responsible for protecting the interests of the patient; in regard to care, rehabilitation and resources. The family members were also burdened with feelings of powerlessness and sadness due to the patients’ suffering. On the contrary, family members of cognitively intact hip fracture patients had positive experiences. The family members expressed pleasure from seeing their close ones make progress. However, when the healing process was delayed this led to strain on the family members.

Conclusions:  The findings suggest the hip fracture patient’s cognitive state is more decisive than the hip fracture itself for the family members’ experiences.
A nutrient‐sensitive interaction between Sirt1 and HNF‐1α regulates Crp expression
Authors: Grimm Andrew A. , Brace Cynthia S. , Wang Ting , Stormo Gary D. , Imai Shin‐Ichiro
Published: December 2010

Silent information regulator 2 (Sir2) orthologs are an evolutionarily conserved family of NAD‐dependent protein deacetylases that regulate aging and longevity in model organisms. The mammalian Sir2 ortholog Sirt1 regulates metabolic and stress responses through the deacetylation of many transcriptional regulatory factors. To elucidate the mechanism by which Sirt1 controls gene expression in response to nutrient availability, we devised a bioinformatic screen combining gene expression analysis with phylogenetic footprinting to identify transcription factors as new candidate partners of Sirt1. One candidate target was HNF‐1α, a homeodomain transcription factor that regulates pancreatic β‐cell and hepatocyte functions and is commonly mutated in patients with maturity‐onset diabetes of the young (MODY). Interestingly, Sirt1 physically interacts with HNF‐1αin vitro but does so in vivo only in nutrient‐restricting conditions. This interaction requires 12–24 h of nutrient restriction and is dependent on protein synthesis. Both nutrient restriction and Sirt1 suppress HNF‐1α transcriptional activity and the expression of one of its target genes, C‐reactive protein (Crp), in mouse primary hepatocytes. Pharmacological inhibition of Sirt1 blocks the suppression of Crp by nutrient restriction. Similarly, Crp expression is also suppressed in fasted and diet‐restricted liver. Furthermore, Sirt1 and HNF‐1α co‐localize on two HNF‐1α binding sites on the Crp promoter, leading to decreased acetylation of lysine 16 of histone H4 at these sites only in response to nutrient restriction. These findings reveal a novel nutrient‐dependent interaction between Sirt1 and HNF‐1α and provide important insight into the molecular mechanism by which Sirt1 mediates the anti‐aging effects of diet restriction.
New perspectives for the treatment of pulmonary hypertension
Authors: Baliga Reshma S , MacAllister Raymond J , Hobbs Adrian J
Published: December 2010

Pulmonary hypertension (PH) is a debilitating disease with a poor prognosis. Therapeutic options remain limited despite the introduction of prostacyclin analogues, endothelin receptor antagonists and phosphodiesterase 5 inhibitors within the last 15 years; these interventions address predominantly the endothelial and vascular dysfunctionS associated with the condition, but simply delay progression of the disease rather than offer a cure. In an attempt to improve efficacy, emerging approaches have focused on targeting the pro‐proliferative phenotype that underpins the pulmonary vascular remodelling in the lung and contributes to the impaired circulation and right heart failure. Many novel targets have been investigated and validated in animal models of PH, including modulation of guanylate cyclases, phosphodiesterases, tyrosine kinases, Rho kinase, bone morphogenetic proteins signalling, 5‐HT, peroxisome proliferator activator receptors and ion channels. In addition, there is hope that combinations of such treatments, harnessing and optimizing vasodilator and anti‐proliferative properties, will provide a further, possibly synergistic, increase in efficacy; therapies directed at the right heart may also offer an additional benefit. This overview highlights current therapeutic options, promising new therapies, and provides the rationale for a combination approach to treat the disease.

LINKED ARTICLES This article is part of a themed issue on Respiratory Pharmacology. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2011.163.issue‐1
Pharmacological enhancement of fear reduction: preclinical models
Authors: Graham Bronwyn M , Langton Julia M , Richardson Rick
Published: December 2010

Anxiety disorders have a high prevalence, and despite the substantial advances in the psychological treatment of anxiety, relapse is still a common problem. One approach to improving existing psychological treatments for anxiety has been to develop pharmacological agents that can be used to enhance the processes underlying exposure therapy, which is the most commonly used and empirically validated psychological treatment for anxiety during which individuals are taught to appropriately inhibit fear. Animal models of exposure therapy, particularly fear extinction, have proved to be a very useful way of examining the neural and molecular correlates of fear inhibition, which has in turn led to the identification of numerous drugs that enhance these processes in rats. Several of these drugs have subsequently been tested as novel pharmacological adjuncts to exposure therapy in humans with a range of anxiety disorders. The purpose of this review is to outline the key animal models of exposure therapy and to describe how these have been used to develop potential pharmacological adjuncts for anxiety disorders. Drugs that are currently in clinical use, as well as those currently in the preclinical stages of investigation, are described.

LINKED ARTICLES This article is part of a themed issue on Translational Neuropharmacology. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2011.164.issue‐4
Quality assessment of 3D building data
Authors: Akca Devrim , Freeman Mark , Sargent Isabel , Gruen Armin
Published: December 2010

Three‐dimensional building models are often now produced from lidar and photogrammetric data. The quality control of these models is a relevant issue both from the scientific and practical points of view. This work presents a method for the quality control of such models. The input model (3D building data) is co‐registered to the verification data using a 3D surface matching method. The 3D surface matching evaluates the Euclidean distances between the verification and input data‐sets. The Euclidean distances give appropriate metrics for the 3D model quality. This metric is independent of the method of data capture. The proposed method can favourably address the reference system accuracy, positional accuracy and completeness. Three practical examples of the method are provided for demonstration.
Survival Disparities within American and Israeli Dialysis Populations: Learning from Similarities and Distinctions across Race and Ethnicity
Authors: Kalantar‐Zadeh Kamyar , Golan Eliezer , Shohat Tamy , Streja Elani , Norris Keith C. , Kopple Joel D.
Published: December 2010

There are counterintuitive but consistent observations that African American maintenance dialysis patients have greater survival despite their less favorable socioeconomic status, high burden of cardiovascular risks including hypertension and diabetes, and excessively high chronic kidney disease prevalence. The fact that such individuals have a number of risk factors for lower survival and yet live longer when undergoing dialysis treatment is puzzling. Similar findings have been made among Israeli maintenance dialysis patients, in that those who are ethnically Arab have higher end‐stage renal disease but exhibit greater survival than Jewish Israelis. The juxtaposition of these two situations may provide valuable insights into racial/ethnic‐based mechanisms of survival in chronic diseases. Survival advantages of African American dialysis patients may be explained by differences in nutritional status, inflammatory profile, dietary intake habits, body composition, bone and mineral disorders, mental health and coping status, dialysis treatment differences, and genetic differences among other factors. Prospective studies are needed to examine similar models in other countries and to investigate the potential causes of these paradoxes in these societies. Better understanding the roots of racial/ethnic survival differences may help improve outcomes in both patients with chronic kidney disease and other individuals with chronic disease states.
Evaluation of Adult Kidney Transplant Candidates
Authors: Pham Phuong‐Thu , Pham Phuong‐Anh , Pham Phuong‐Chi , Parikh Sefali , Danovitch Gabriel
Published: December 2010

Important advances in immunosuppressive therapy and refinement in surgical techniques have allowed renal transplantation to become the treatment of choice for virtually all suitable candidates with end‐stage renal disease. Compared to dialysis, kidney transplantation improves both patient survival and quality of life and, over time, can reduce the total cost of medical care. It must be noted, however, that although the risk of death in the first year after transplantation is <5%, not all patients qualify for the surgery because of their unacceptable risks for complications. The transplant evaluation process requires a comprehensive assessment of each patient’s medical, surgical, and psychosocial histories. Selection of the suitable transplant candidate remains a challenge for transplant physicians owing, predominantly, to the presence of complex medical issues in the potential candidates and nonstandardized criteria for acceptance or rejection among transplant centers. Furthermore, with the ever‐increasing disparity between donor organ supply and demand and resultant increased wait‐list times, the transplant physicians must further consider the optimal management and re‐evaluation of wait‐list patients during the waiting period. This article describes a systematic approach for the evaluation of a potential renal transplant candidate. Various medical issues that arise during the evaluation process are discussed.
Lack of effect of unrefrigerated young whole blood transfusion on patient outcomes after massive transfusion in a civilian setting
Authors: Ho Kwok M. , Leonard Anton D.
Published: December 2010

BACKGROUND: Warm fresh whole blood has been advocated for critical bleeding in the military setting. This study assessed whether unrefrigerated young whole blood transfusion, from donation to transfusion less than 24 hours, could reduce mortality of patients with critical bleeding in a civilian setting.

STUDY DESIGN AND METHODS: A linked data cohort study was conducted on a total of 353 consecutive patients requiring massive transfusion, defined as 10 units or more of red blood cells or whole blood transfusion within 24 hours, in a quaternary health care center in Australia.

RESULTS: Of the 353 patients with massive blood transfusion in the study, 77 received unrefrigerated young whole blood transfusion (mean, 4.0 units; interquartile range, 2‐6). The diagnosis, severity of acute illness, age, sex, and ABO blood group were not significantly different between the patients who received unrefrigerated young whole blood and those who did not. Unrefrigerated young whole blood transfusions were associated with a slightly improved coagulation profile (lowest fibrinogen concentrations 1.7 g/L vs. 1.4 g/L, p = 0.006; worst international normalization ratio, 2.4 vs. 2.8, p = 0.05) but did not reduce the total utilization of allogeneic blood products and subsequent use of recombinant Factor VIIa (27% vs. 22%, p = 0.358). Thirty‐day mortality and 8‐year survival after hospital discharge (hazard ratio, 1.05; 95% confidence interval, 0.41‐2.65; p = 0.93) were also not different after the use of unrefrigerated young whole blood transfusion.

CONCLUSIONS: Unrefrigerated young whole blood transfusion was not associated with a reduced mortality of patients requiring massive transfusion in a civilian setting when other blood products were readily available.
Estimation of the Likelihood of Fecal–Oral HEV Transmission Among Pigs
Authors: Bouwknegt Martijn , Teunis Peter F. M. , Frankena Klaas , de Jong Mart C. M. , de Roda Husman Ana Maria
Published: December 2010

Sources for human hepatitis E virus (HEV) infections of genotype 3 are largely unknown. Pigs are potential animal reservoirs for HEV. Intervention at pig farms may be desired when pigs are confirmed as a source for human infections, requiring knowledge about transmission routes. These routes are currently understudied. The current study aims to quantify the likelihood of pig feces in causing new HEV infections in pigs due to oral ingestion. We estimated the daily infection risk for pigs by modeling the fate of HEV in the fecal–oral (F–O) pathway. Using parameter values deemed most plausible by the authors based on current knowledge the daily risk of infection was 0.85 (95% interval: 0.03–1). The associated expected number of new infections per day was ∼4 (2.5% limit 0.1, the 97% limit tending to infinity) compared to 0.7 observed in a transmission experiment with pigs, and the likelihood of feces causing the transmission approached 1. In alternative scenarios, F–O transmission of HEV was also very likely to cause new infections. By reducing the total value of all explanatory variables by 2 orders of magnitude, the expected numbers of newly infected pigs approached the observed number. The likelihood of F–O transmission decreased by decreasing parameter values, allowing for at most 94% of infections being caused by additional transmission routes. Nevertheless, in all scenarios F–O transmission was estimated to contribute to HEV transmission. Thus, despite the difficulty in infecting pigs with HEV via oral inoculation, the F–O route is likely to cause HEV transmission among pigs.
A Probabilistic Transmission Model to Assess Infection Risk fromMycobacterium Tuberculosisin Commercial Passenger Trains
Authors: Chen Szu‐Chieh , Liao Chung‐Min , Li Sih‐Syuan , You Shu‐Han
Published: December 2010

The objective of this article is to characterize the risk of infection from airborneMycobacterium tuberculosisbacilli exposure in commercial passenger trains based on a risk‐based probabilistic transmission modeling. We investigated the tuberculosis (TB) infection risks among commercial passengers by inhaled aerosol M. tuberculosis bacilli and quantify the patterns of TB transmission in Taiwan High Speed Rail (THSR). A deterministic Wells‐Riley mathematical model was used to account for the probability of infection risk from M. tuberculosis bacilli by linking the cough‐generated aerosol M. tuberculosis bacilli concentration and particle size distribution. We found that (i) the quantum generation rate of TB was estimated with a lognormal distribution of geometric mean (GM) of 54.29 and geometric standard deviation (GSD) of 3.05 quantum/h at particle size ≤ 5 μm and (ii) the basic reproduction numbers (R0) were estimated to be 0.69 (0.06–6.79), 2.82 (0.32–20.97), and 2.31 (0.25–17.69) for business, standard, and nonreserved cabins, respectively. The results indicate that commercial passengers taking standard and nonreserved cabins had higher transmission risk than those in business cabins based on conservatism. Our results also reveal that even a brief exposure, as in the bronchoscopy cases, can also result in a transmission when the quantum generation rate is high. This study could contribute to a better understanding of the dynamics of TB transmission in commercial passenger trains by assessing the relationship between TB infectiousness, passenger mobility, and key model parameters such as seat occupancy, ventilation rate, and exposure duration.
Pregnancy planning in Sweden – a pilot study among 270 women attending antenatal clinics
Authors: TYDÉN TANJA , STERN JENNY , NYDAHL MARGARETHA , BERGLUND ANNA , LARSSON MARGARETA , ROSENBLAD ANDREAS , AARTS CLARA
Published: December 2010

Objective. Health status and lifestyle before and at the time of conception could affect the health of both mother and child, but there is a lack of knowledge about the degree to which pregnancies are planned. The aim of this pilot study was to investigate whether and how women plan their pregnancies. Material and methods. The main outcome measures were use of timetables, ovulation tests and lifestyle changes. Women (n= 322) visiting four antenatal clinics were asked to fill out a questionnaire (participation rate = 83.9%, n= 270). Results. Three of four pregnancies (n= 202) were very or rather well planned, whereas 4.4% (n= 12) were totally unplanned. During the planning period, 37.1% (n= 100) made up a timetable for getting pregnant, 23% (n= 62) used ovulation tests, 20.7% (n= 56) took folic acid and 10.4% (n= 28) changed alcohol consumption. Conclusion. Although a majority of these women had planned pregnancies, only one in five had taken folic acid during the planning period.
Emergency cesarean sections can be predicted by markers for stress, worry and sleep disturbances in first‐time mothers
Authors: WANGEL ANNE‐MARIE , MOLIN JOHAN , ÖSTMAN MARGARETA , JERNSTRÖM HELENA
Published: December 2010

Objective. To identify predictors as free‐text markers for mental ill‐health from an electronic perinatal record (EMR) system and the association with emergency cesarean section (CS) in nulliparous women. Material and methods. This was a population‐based study using an EMR system, set in the catchment area of Malmö University Hospital in Sweden. Of 10 662 nulliparous women presenting with a singleton cephalic baby for vaginal delivery between 2001 and 2006, 6 467 women with complete EMRs were selected. A free‐text search of markers for mental ill‐health was carried out, and results were analysed by multivariate logistic regression. Eleven markers for mental ill‐health were tested with Cohen's kappa for agreement and used as exposure variables. Odds ratios (OR) with 95% confidence intervals (CI) were calculated for emergency CS, and adjusted for maternal age, diabetes, epidural anesthesia and gestational weeks <37 and >41 by a multivariate logistic regression model with vaginal delivery as the reference. Results. Three markers identified from the EMR system reached statistically significant associations with an increased risk for emergency CS in nulliparous women: stress, adjusted OR 1.66 (95% CI 1.34–2.06); sleep, adjusted OR 1.57 (95% CI 1.14–2.16); and worry, adjusted OR 1.41 (95% CI 1.10–1.79). Conclusion. Free‐text words in medical records that indicated stress, sleep disturbances or worry predicted increased adjusted OR for emergency CS in first‐time mothers. Recognizing pregnant women's reporting of their mental health status could have a predictive bearing on delivery outcomes.
Exposure to Phosphodiesterase Type 5 Inhibitors Stimulates Aromatase Expression in Human Adipocytes in vitro
Authors: Aversa Antonio , Caprio Massimiliano , Antelmi Antonella , Armani Andrea , Brama Marina , Greco Emanuela A. , Francomano Davide , Calanchini Matilde , Spera Giovanni , Luigi Luigi Di , Rosano Giuseppe M.C. , Lenzi Andrea , Migliaccio Silvia , Fabbri Andrea
Published: December 2010

Introduction

Prolonged tadalafil administration in men with erectile dysfunction is associated with increased testosterone (T): estradiol (E2) ratio mainly related to reduction of E2 levels.

Aim

To investigate the presence of phosphodiesterase type 5 (PDE5) isoenzyme in primary human visceral adipocytes and whether different PDE5 inhibitors (PDE5i) could directly modulate aromatase (ARO) expression in differentiated human visceral adipocytes in culture.

Main Outcome Measures

PDE5 mRNA and protein expression in primary human visceral adipocytes as well as mRNA and protein expression of ARO, with functional activity after selective PDE5 blockade by tadalafil and sildenafil.

Methods

Purified primary human visceral pre-adipocytes were differentiated ex vivo and were exposed to tadalafil or sildenafil (1 µM) for different intervals of time (6-12-24-96 hours). ARO mRNA content and expression were measured by Western Blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR), respectively. T and E2 in supernatants were measured by ELISA also in the presence of letrozole.

Results

Differentiated adipocytes were found to express detectable levels of PDE5 transcripts. Acute exposure (6 hours) to both PDE5i tadalafil and sildenafil increased ARO mRNA expression by 4.7- and 2.8-fold, respectively (P < 0.001). ARO mRNA and protein levels were increased by the treatment with PDE5i in a time- and dose-dependent manner. Such effect was mimicked by 8-bromo-cGMP but was lost after 24 and 96 hours; differently, the PDE3B specific inhibitor milrinone (1 µM), displayed no effect. Accordingly, long-term exposure (24 and 96 hours) to PDE5i caused a significant increase in E2 concentrations in the supernatant (1.7 and 2 fold, respectively; P < 0.001), with a parallel reduction of T (15% and 30%, respectively; P < 0.001). Such effect was reversed by the co-incubation with the specific ARO-inhibitor letrozole.

Conclusions

Our results demonstrate that PDE5 is expressed in human visceral adipocytes and that acute exposure to PDE5i selectively stimulates ARO expression, which is related to a specific PDE5 blockade. We speculate that modulation of ARO activity by PDE5i could be one of the mechanisms responsible, at least in part, for the beneficial effects of PDE5i on endothelial and metabolic functions.
Clostridium difficile: progress and challenges
Authors: Bartlett John G.
Published: December 2010

There is a surge of new interest in C. difficile infection (CDI) reflecting substantial increases in cases and fatalities. The new challenges by this now old pathogen have brought renewed interest in all facets of the disease. Particularly important are the role of fluoroquinolones as inducing agents, the new polymerase chain reaction test to detect toxigenic strains in stools, the important role of the NAP‐1 strain, recent evidence favoring oral vancomycin over metronidazole in seriously ill patients, and new guidelines for management.
Investigation of Mendelian forms of obesity holds out the prospect of personalized medicine
Authors: Blakemore Alexandra I. F. , Froguel Philippe
Published: December 2010

Mendelian forms of obesity are already known to account for approximately 5% of the severely obese but are currently underinvestigated. In contrast, there has been much recent concentration on genome‐wide single nucleotide polymorphism (SNP) associations in obesity, with particular emphasis given to the role of the fat mass and obesity associated (FTO) gene. Unfortunately, despite the enormous resources devoted to this work, none of the SNP markers in the ∼30 genes discovered to have associations with common obesity have meaningful predictive power. This is very different from the situation for Mendelian obesity, where mutations have very clear effects on phenotype. Study of Mendelian obesity has also added significantly to our understanding of mechanisms of appetite regulation, with all known causative genes being active in the brain and most forming part of the leptin–melanocortin signaling pathway. Investigation of genomic structural variation has also recently revealed deletions causing obesity, sometimes with concomitant neurocognitive dysfunction. Advances in next‐generation sequencing are expected to uncover additional highly penetrant causes of obesity. Screening for Mendelian forms of obesity is rarely carried out but holds considerable promise for improved clinical care of these high‐risk patients.
Alteration Geochemistry of Volcanic Rocks around Sarcheshmeh Porphyry Copper Deposit, Rafsanjan, Kerman, Iran: Implications for Regional Exploration
Authors: Aftabi Alijan , Atapour Habibeh
Published: December 2010

To discriminate the mineral potentiality of the trachybasalt around the Miocene Sarcheshmeh porphyry copper deposit, petrogeochemical characteristics of more than 45 samples of the volcanic rocks were studied. Sarcheshmeh is one of the world's largest Miocene porphyry copper deposits in a continental arc setting and contains about 1200 million tonnes of ores with an average grade of 1.2 percent copper, 0.03 percent molybdenum, 3.9 g/t Ag and 0.11 g/t Au. The biotized and sericitized trachybasalts around the Sarcheshmeh deposit are associated with chalcopyrite, pyrite and molybdenite and and are enriched in Cu (>3108 ppm), K2O (>4.2%), Rb (>155 ppm) and MgO (>2.9%), but depleted in yttrium (<11 ppm), MnO (<0.06%), CaO (<0.6%), Na2O (<0.33%), Sr (<107 ppm), and Ba (<181 ppm). The propylitized trachybasalts are enriched in CaO (>9.1%), Na2O (>3.2%), MnO (>0.24%), Y (>18.2 ppm), and Ba (>323 ppm). The results demonstrate that the diagrams of loss on ignition − Cu, Cu − Y, K2O/K2O + Na2O + CaO − Cu and Y − MnO may be used as an exploration guide for undiscovered porphyry copper mineralization in the Central Iranian volcano—plutonic copper belt.