bluuebunny/crossref_metadata_2025 huggingface dataset:
Facing haematopoietic stem‐cell transplantation: do patients and their physicians agree regarding the prognosis?
Authors: Grulke Norbert , Bailer Harald
Published: December 2009

Objective: To evaluate the correlation and concordance between patients' and physicians' estimations of prognoses before initiation of the conditioning regimen for allogeneic haematopoietic stem‐cell transplantation.

Methods: A total of 123 patients and their attending physicians were asked to estimate a prognosis on a six‐point scale. The patients were also asked to fill out questionnaires addressing their psychological state and coping.

Results: The mean prognostic estimations differed by 1.17 points (p<0.001), with the patients being more optimistic than the physicians. With respect to concordance: Pearson correlation r=0.024 (ns); unweighted kappa and kappa with linear weighting are 0.115 and 0.068, respectively. The prognostic estimates of the patients correlated with their psychological state, but not with the objective disease‐ or treatment‐related variables, whereas the physicians' estimates were partially based on such objective factors.

Conclusions: A clear significant association between actual survival and the physicians' estimates, but not the patients' estimates, was observed. If agreement regarding the prognosis exists, the relationship between physicians' and patients' estimates is probably non‐linear. Assessing one's chances of being cured is a highly emotional task, and psychological processes such as denial or repression most likely play a decisive role. Moreover, collusion between the patient and physician may be inevitable in this situation. Whether it is desirable to gain concordance and who will benefit from such efforts must be discussed and empirically studied. Copyright © 2009 John Wiley & Sons, Ltd.
Prenatal diagnosis and outcome of partial agenesis and hypoplasia of the corpus callosum
Authors: Ghi T. , Carletti A. , Contro E. , Cera E. , Falco P. , Tagliavini G. , Michelacci L. , Tani G. , Youssef A. , Bonasoni P. , Rizzo N. , Pelusi G. , Pilu G.
Published: December 2009

Objective

To present antenatal sonographic findings and outcome of fetuses with hypoplasia or partial agenesis of the corpus callosum.

Methods

The database of our ultrasound laboratory was searched retrospectively for cases of hypoplasia or partial agenesis of the corpus callosum suspected at antenatal neurosonography between 1998 and 2008 and confirmed by pathology or postnatal neuroimaging. In surviving infants, clinical follow‐up had been arranged to assess neurodevelopmental outcome.

Results

Nineteen fetuses with callosal underdevelopment were identified at a median gestational age of 22 (range, 21–33) weeks and confirmed at follow‐up, including 14 with partial agenesis and five with hypoplasia. Among the 14 fetuses with partial agenesis, there were additional brain findings in 10, including two with absent cavum septi pellucidi, four with mild isolated ventriculomegaly and four with cerebellar abnormalities, two of which also had ventriculomegaly. Pregnancy was terminated electively in seven of the cases with partial agenesis and there was one neonatal death. Among the six surviving infants, neurodevelopmental outcome was appropriate for age in three at follow up, including two cases with isolated partial agenesis of the corpus callosum. Among the five fetuses with prenatally diagnosed callosal hypoplasia, additional anomalies were present in four. Two cases were terminated electively and three were alive at the time of writing, with a median age of 3 years. Among them, apparently normal neurological development was observed in only one case.

Conclusions

An antenatal diagnosis of callosal underdevelopment is possible by expert sonography. There is often association with other major anomalies. However, even in fetuses with apparently isolated findings, the prognosis is uncertain. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Sleep patterns and impulse control among Japanese junior high school students
Authors: Abe Takeru , Hagihara Akihito , Nobutomo Koichi
Published: December 2009

Adolescents with decreased impulse control exhibit behavioral problems. Lifestyles are related to impulse control. However, the relations of sleep patterns and impulse control among adolescents are unknown. Thus we examined how sleep patterns were associated with impulse control among Japanese junior high school students. Surveys were completed by a nationwide sample of 1934 students. A significant association between decreased impulse control and bedtimes after midnight was revealed. Specific lifestyle factors related to bedtimes after midnight were older age, greater numbers of hours spent watching television, lack of participation in an extracurricular activity, greater use of convenience stores, and increased attendance at cram schools. This study revealed that going to sleep after midnight was significantly related to decreased impulse control among adolescents. Data about specific lifestyle factors related to going to sleep after midnight should be useful in preventing those behaviors demonstrated by school children that derive from decreased impulse control.
Effects of pain management on sleep in preterm infants
Authors: Axelin Anna , Kirjavainen Jarkko , Salanterä Sanna , Lehtonen Liisa
Published: December 2009

Background: This study was conducted to gain better understanding of the prolonged effects of pain and pain management on preterm infants’ sleep.

Aim: The hypothesis was that the sleep structure in very preterm infants is different after painful procedures with pain management (facilitated tucking by parents (FTP), oral glucose, and oxycodone) than without pain management (oral water as placebo).

Methods: A prospective randomized placebo‐controlled cross‐over trial design was used. Thirteen‐hour polysomnographic recordings were conducted when the study infants (n = 18) were at a post‐conceptional age of 28–32 weeks. During the recordings, the standardized nursing care periods were carried out with different forms of pain management administered at 3‐h intervals. Sleep structure was analyzed before and after the interventions. The main hypothesis was analyzed using mixed models.

Results: During the first post‐intervention hour, the amount of rapid eye movement (REM) sleep decreased after all interventions regardless of pain management (p < 0.001). However, the oxycodone treatment further reduced the amount of REM sleep to 48.0% (SD 14.9) compared to other interventions: oral glucose to 64.4% (SD 12.8), (p < 0.001); placebo to 62.9% (SD 16.1), (p < 0.001); and FTP to 61.6% (SD 1.9), (p = 0.004). In addition, sleep onset comprised non‐rapid eye movement (NREM) sleep more frequently after oxycodone (50%) compared to placebo (6%, p = 0.006), oral glucose (11%, p = 0.019) or FTP (17%, p = 0.056).

Conclusion: Pain management with oxycodone markedly altered the structure of the subsequent sleep period. This reduced amount of REM sleep may have consequences for brain development in preterm infants.
Duration and adherence of antidepressant treatment (2003 to 2007) based on prescription database
Authors: Serna M.C. , Cruz I. , Real J. , Gascó E. , Galván L.
Published: December 2009

Background

Many patients discontinue antidepressant therapy long before the six-month minimum duration recommended for the treatment of major depression and many other diagnoses.

Purpose

To estimate the duration of antidepressant treatment and to analyse the following factors in relation to treatment adherence: age, sex, polypharmacy and type of drug.

Methods

Retrospective cohort followed up for five years (2003–2007) based on prescription database. Selection criteria: Users who had received at least one antidepressant prescription in 2003 and who had not received antidepressants during the previous 12 months.

Variables studied

Age, sex, drug, polypharmacy, period of treatment, packs dispensed. Adequate adherence was defined as dispensation of medication during at least 80% of the treatment period, and compliance was defined as good when, in addition, the treatment lasted more than four months.

Results

Of the 7525 patients selected, 56% abandoned medication during the first four months. Men were more likely to give up medication before time than women. Good compliance was recorded in 22% of patients and was twice as frequent in patients with high levels of polypharmacy than in those with low levels (31% vs. 15.3%). Patients receiving maprotiline, venlafaxine, mirtazapine, citalopram, clomipramine and fluoxetine presented the highest percentages of good compliance.

Conclusions

Only one out of five patients complied with treatment for over four months. Treatment periods were shorter in men. In chronic processes, patients receiving polypharmacy presented the best compliance.
The omega‐3 fatty acid, DHA, decreases neuronal cell death in association with altered zinc transport
Authors: Suphioglu Cenk , De Mel Damitha , Kumar Loveleen , Sadli Nadia , Freestone David , Michalczyk Agnes , Sinclair Andrew , Ackland M. Leigh
Published: December 2009

Docosahexaenoic acid (DHA) is the major polyunsaturated fatty acid in neuronal cell membranes. We hypothesize that DHA induces a decrease in neuronal cell death through reduced ZnT3 expression and zinc uptake. Exposure of M17 cells to DHA‐deficient medium increased the levels of active caspase‐3, relative to levels in DHA‐replete cells, confirming the adverse effects of DHA deficiency in promoting neuronal cell death. In DHA‐treated M17 cells, zinc uptake was 65% less and ZnT3 mRNA and protein levels were reduced in comparison with DHA‐depleted cells. We propose that the neuroprotective function of DHA is exerted through a reduction in cellular zinc levels that in turn inhibits apoptosis.
Government communication and democratic governance: Electoral and policy-related information campaigns in Canada
Authors: Howlett Michael , Craft Jonathan , Zibrik Lindsay
Published: December 2009

Government communication is now a large growth industry in many countries. Exactly what is meant by the term, however, varies from author to author. In this paper government communication is conceived as a policy tool or instrument, that is, as a means to give effect to policy goals. Key policy-relevant aspects of the term are examined including differences between the role of government communications in the ‘front-end’ of the public policy and production processes related to agenda-setting, policy formulation and producer activities as opposed to the ‘back-end’ of policy implementation, policy evaluation, consumption and distribution. Two case studies of political and policy-related information campaigns in Canada, one dealing with Elections Canada at the federal level and the second with provincial health policy-making in British Columbia, are examined in order to discern patterns in the use of government communication tools useful as a basis for comparative inquiry into Democratic governance.
Test objects and other epistemic things: a history of a nanoscale object
Authors: MODY CYRUS C.M. , LYNCH MICHAEL
Published: December 2009

This paper follows the history of an object. The purpose of doing so is to come to terms with a distinctive kind of research object – which we are calling a ‘test object’ – as well as to chronicle a significant line of research and technology development associated with the broader nanoscience/nanotechnology movement. A test object is one of a family of epistemic things that makes up the material culture of laboratory science. Depending upon the case, it can have variable shadings of practical, mathematical and epistemic significance. Clear cases of test objects have highly regular and reproducible visible properties that can be used for testing instruments and training novices. The test object featured in this paper is the silicon (111) 7×7, a particular surface configuration (or, as it is often called, a ‘reconstruction’) of silicon atoms. Research on this object over a period of several decades has been closely bound up with the development of novel instruments for visualizing atomic structures. Despite having little direct commercial value, the Si(111) 7×7 also has been a focal object for the formation of a research community bridging industry and academia. It exhibits a complex structure that became a sustained focus of observation and modelling. Our study follows shifts in the epistemic status of the Si(111) 7×7, and uses it to re-examine familiar conceptions of representation and observation in the history, philosophy and social study of science.
Drag and lift forces on particles in a rotating flow
Authors: BLUEMINK J. J. , LOHSE D. , PROSPERETTI A. , VAN WIJNGAARDEN L.
Published: December 2009

A freely rotating sphere in a solid-body rotating flow is experimentally investigated. When the sphere is buoyant, it reaches an equilibrium position from which drag and lift coefficients are determined over a wide range of particle Reynolds numbers (2 ≤ Re ≤ 1060). The wake behind the sphere is visualized and appears to deflect strongly when the sphere is close to the cylinder axis. The spin rate of the sphere is recorded. In fluids with low viscosity, spin rates more than twice as large as the angular velocity of the cylinder can be observed. By comparing numerical results for a fixed but freely spinning sphere with a fixed non-spinning sphere for Re ≤ 200, the effect of the sphere spin on the lift coefficient is determined. The experimentally and numerically determined lift and drag coefficients and particle spin rates all show excellent agreement for Re ≤ 200. The combination of the experimental and numerical results allows for a parameterization of the lift and drag coefficients of a freely rotating sphere as function of the Reynolds number, the particle spin and the location of the particle with respect to the cylinder axis. Although the effect of the flow rotation on the particle spin is different in shear flow and solid-body rotating flow, the effect of spin on lift is found to be comparable for both types of flow.
Quantitative risk assessment to compare the risk of rabies entering the UK from Turkey via quarantine, the Pet Travel Scheme and the EU Pet Movement Policy
Authors: RAMNIAL V. , KOSMIDER R. , AYLAN O. , FREULING C. , MÜLLER T. , FOOKS A. R.
Published: December 2009

Rabies was eradicated from the UK in 1922 through strict controls of dog movement and investigation of every incident of disease. Amendments were made to the UK quarantine laws and the Pet Travel Scheme (PETS) was subsequently introduced in 2000 for animals entering the UK from qualifying listed countries. European Regulation 998/2003 on the non-commercial movement of pet animals initiated the European Union Pet Movement Policy (EUPMP) in July 2004. The introduction of EUPMP harmonized the movement of pet animals within the EU (EUPMPlisted) but raised the possibility of domestic animals entering the UK from a non-EU state where rabies is endemic (EUPMPunlisted). A quantitative risk assessment was developed to estimate the risk of rabies entering the UK from Turkey via companion animals that are incubating the disease and enter through PETS or EUPMP compared to quarantine. Specifically, the risk was assessed by estimating the annual probability of rabies entering the UK and the number of years between rabies entries for each scheme. The model identified that the probability of rabies entering the UK via the three schemes is highly dependent on compliance. If 100% compliance is assumed, PETS and EUPMPunlisted(at the current level of importation) present a lower risk than quarantine, i.e. the number of years between rabies entry is more than 170 721 years for PETS and 60 163 years for EUPMPunlistedcompared to 41 851 years for quarantine (with 95% certainty). If less than 100% compliance is assumed, PETS and EUPMPunlisted(at the current level of importation) present a higher risk. In addition, EUPMPlistedand EUPMPunlisted(at an increased level of importation) present a higher risk than quarantine or PETS at 100% compliance and at an uncertain level of compliance.
A cost-utility analysis of antenatal screening to prevent congenital rubella syndrome
Authors: LUGNÉR A. K. , MOLLEMA L. , RUIJS W. L. M. , HAHNÉ S. J. M.
Published: December 2009

In low vaccination coverage regions (LVR) in The Netherlands people often reject participation in the National Immunization Programme for religious reasons. During a rubella epidemic in 2004–2005, 32 pregnant women were notified with rubella, and 11 babies were born with defects related to maternal infection. This study presents a cost-utility analysis of a screening and vaccination programme for rubella focusing on three scenarios: (1) screening non-vaccinated pregnant women in LVR; (2) screening all pregnant women in LVR; (3) screening all non-vaccinated pregnant women in The Netherlands (including pregnant first-generation non-Western immigrant women). Cost-utility was estimated over a 16-year period which included two rubella outbreaks. Observed complications from the 2004–2005 epidemic were used to estimate average cost savings and quality-adjusted life-years (QALY) gained. The programme would be cost-effective (€1100/QALY gained) when assuming an acceptability of vaccination of 20% in women belonging to orthodox protestant risk groups.
Shear‐induced dilatancy of fluid‐saturated faults: Experiment and theory
Authors: Samuelson Jon , Elsworth Derek , Marone Chris
Published: December 2009

Pore fluid pressure plays an important role in the frictional strength and stability of tectonic faults. We report on laboratory measurements of porosity changes associated with transient increases in shear velocity during frictional sliding within simulated fine‐grained quartz fault gouge (d50 = 127 μm). Experiments were conducted in a novel true triaxial pressure vessel using the double‐direct shear geometry. Shearing velocity step tests were used to measure a dilatancy coefficient (ɛ = Δϕ/Δln(v), where ϕ is porosity and v is shear velocity) under a range of conditions: background shearing rate of 1 μm/s with steps to 3, 10, 30, and 100 μm/s at effective normal stresses from 0.8 to 20 MPa. We find that the dilatancy coefficient ranges from 4.7 × 10−5 to 3.0 × 10−4 and that it does not vary with effective normal stress. We use our measurements to model transient pore fluid depressurization in response to dilation resulting from step changes in shearing velocity. Dilatant hardening requires undrained response with the transition from drained to undrained loading indexed by the ratio of the rate of porosity change to the rate of drained fluid loss. Undrained loading is favored for high slip rates on low‐permeability thick faults with low critical slip distances. Although experimental conditions indicate negligible depressurization due to relatively high system permeability, model results indicate that under feasible, but end‐member conditions, shear‐induced dilation of fault zones could reduce pore pressures or, correspondingly, increase effective normal stresses, by several tens of megapascals. Our results show that transient increases in shearing rate cause fault zone dilation. Such dilation would tend to arrest nucleation of unstable slip. Pore fluid depressurization would exacerbate this effect and could be a significant factor in generation of slow earthquakes, nonvolcanic tremors, and related phenomena.
Interleukin‐15 Contributes to the Regulation of Murine Adipose Tissue and Human Adipocytes
Authors: Barra Nicole G. , Reid Sarah , MacKenzie Randy , Werstuck Geoff , Trigatti Bernardo L. , Richards Carl , Holloway Alison C. , Ashkar Ali A.
Published: December 2009

An alarming global rise in the prevalence of obesity and its contribution to the development of chronic diseases is a serious health concern. Recently, obesity has been described as a chronic low‐grade inflammatory condition, influenced by both adipose tissue and immune cells suggesting proinflammatory cytokines may play a role in its etiology. Here we examined the effects of interleukin‐15 (IL‐15) on adipose tissue and its association with obesity. Over expression of IL‐15 (IL‐15tg) was associated with lean body condition whereas lack of IL‐15 (IL‐15−/−) results in significant increase in weight gain without altering appetite. Interestingly, there were no differences in proinflammatory cytokines such as IL‐6 and tumor necrosis factor‐α (TNF‐α) in serum between the three strains of mice. In addition, there were significant numbers of natural killer (NK) cells in fat tissues from IL‐15tg and B6 compared to IL‐15−/− mice. IL‐15 treatment results in significant weight loss in IL‐15−/− knockout and diet‐induced obese mice independent of food intake. Fat pad cross‐sections show decreased pad size with over expression of IL‐15 is due to adipocyte shrinkage. IL‐15 induces weight loss without altering food consumption by affecting lipid deposition in adipocytes. Treatment of differentiated human adipocytes with recombinant human IL‐15 protein resulted in decreased lipid deposition. In addition, obese patients had significantly lower serum IL‐15 levels when compared to normal weight individuals. These results clearly suggest that IL‐15 may be involved in adipose tissue regulation and linked to obesity.
Elevated Insulin Sensitivity in Low‐protein Offspring Rats Is Prevented by a High‐fat Diet and Is Associated With Visceral Fat
Authors: Gosby Alison K. , Maloney Christopher A. , Caterson Ian D.
Published: December 2009

This study tests the hypothesis that a high‐fat postnatal diet increases fat mass and reduces improved insulin sensitivity (IS) found in the low‐protein model of maternal undernutrition. Offspring from Wistar dams fed either a 20% (control (CON)) or 8% (low protein (LP)) protein diet during gestation and lactation were randomly assigned to a control (con) or cafeteria (caf) diet at weaning (21 days) until 3 months of age at which point IS was measured (hyperinsulinemic–euglycemic clamp). Fat mass, growth, energy intake (EI) and expenditure (EE), fuel utilization, insulin secretion, and leptin and adiponectin levels were measured to identify a possible role in any changes in IS. IS was increased in LP‐con in comparison to CON‐con animals. Cafeteria feeding prevented this increase in LP animals but had no effect in CON animals (insulin‐stimulated glucose infusion rates (GIRs; mg/min/kg); CON‐con: 13.9 ± 1.0, CON caf: 12.1 ± 2.1, LP‐con: 25.4 ± 2.0, LP‐caf: 13.7 ± 3.7, P < 0.05). CON‐caf animals had similar percent epididymal white adipose tissue (%EWAT; CON‐con: 1.71 ± 0.09 vs. CON‐caf: 1.66 ± 0.08) and adiponectin (µg/ml: CON‐con: 4.61 ± 0.34 vs. CON‐caf: 3.67 ± 0.18) except hyperinsulinemia and relative hyperleptinemia in comparison to CON‐con. Differently, LP‐caf animals had increased %EWAT (LP‐con: 1.11 ± 0.06 vs. LP‐caf: 1.44 ± 0.08, P < 0.05) and adiponectin (µg/ml: LP‐con: 5.38 ± 0.39 vs. LP‐caf: 3.75 ± 0.35, P < 0.05) but did not show cafeteria‐induced hyperinsulinemia or relative hyperleptinemia. An increased propensity to store visceral fat in LP animals may prevent the elevated IS in LP offspring.
Cut‐points for Waist Circumference in Europids and South Asians
Authors: Cameron Adrian J. , Sicree Richard A. , Zimmet Paul Z. , Alberti K. George M.M. , Tonkin Andrew M. , Balkau Beverley , Tuomilehto Jaakko , Chitson Pierrot , Shaw Jonathan E.
Published: December 2009

There is little strong evidence that currently recommended higher waist circumference cut‐points for Europids compared with South Asians are associated with similar risk for type 2 diabetes. This study was designed to provide such evidence. Longitudinal studies over 5 years were conducted among 5,515 Europid and 2,214 ethnically South Asian participants. Age‐standardized diabetes incidence at different levels of waist circumference and incidence difference relative to a reference value were calculated. The Youden Index was used to determine waist circumference cut‐points. At currently recommended cut‐points, estimated annual diabetes incidence for a 50‐year‐old Europid was <0.6% for both sexes, and for a 50‐year‐old South Asian, 5.8% for men and 2.1% for women. Annual diabetes incidence of 1% was observed for a 50 year old at a waist circumference 35–40 cm greater in Europid compared to South Asian men and women. Incidence difference between recommended cut‐points and a reference value (80 cm in men, 70 cm in women) was 0.3 and 4.4% per year for Europid and South Asian men, and 0.2 and 0.8% per year for Europid and South Asian women, respectively. Waist circumference cut‐points chosen using the Youden Index were shown to be dependent on obesity levels in the population. The much higher observed risk of diabetes in South Asians compared to Europids at the respective recommended waist circumference cut‐points suggests that differences between them should be greater. Approaches that use the Youden Index to select waist circumference cut‐points are inappropriate and should not be used for this purpose.
Family Physicians' Barriers to Cancer Screening in Extremely Obese Patients
Authors: Ferrante Jeanne M. , Fyffe Denise C. , Vega Marielos L. , Piasecki Alicja K. , Ohman‐Strickland Pamela A. , Crabtree Benjamin F.
Published: December 2009

Extremely obese women are less likely than nonobese women to receive breast and cervical cancer screening examinations. Reasons for this disparity are unclear and may stem from patient and/or physician barriers. This sequential mixed‐methods study used individual in‐depth interviews of 15 family physicians followed by a mail survey of 255 family physicians (53% response rate) to understand the barriers they faced in performing cancer screening examinations in extremely obese women. Barriers fell into three main areas: (i) difficulty doing pelvic and breast exams; (ii) inadequate equipment; and (iii) challenges overcoming patient barriers and refusal. This led some physicians to avoid performing breast and pelvic examinations on extremely obese women. Having more knowledge about specific examination techniques was associated with less difficulty in palpating lumps on breast and pelvic examinations (P < 0.005). Physicians perceived that embarrassment, aversion to undressing, and avoidance of discussions related to their weight were the most frequent barriers extremely obese women had with getting physical examinations. Educating and/or motivating patients and addressing fears were strategies used most frequently when patients refused mammograms or Pap smears. Interventions focusing on physician barriers, such as educating them on specific examination techniques, obtaining adequate equipment and supplies, and providing resources to assist physicians in dealing with patient barriers and refusal, may be fruitful in increasing cancer screening rates in extremely obese patients. Future research studies testing the effectiveness of these strategies are needed to improve cancer outcomes in this high‐risk population.
Tolerance of Stereopsis to Conjunctive Cyclorotation
Authors: Darmohray Dana , Zhou Bin , Poeppel Ernst
Published: December 2009

Stereopsis is largely unperturbed by various types of eye, head, and target movements. Here, we used a simple setup to investigate the limits of a previously untested type of stimulus motion on stereoscopic depth perception. Clockwise and counterclockwise rotations of an auto-stereogram were used to describe the limits of stereopsis to roll-tilt. The result showed intact depth perception with stimulus rotation up to ∼ 12°, regardless of rotation direction and viewing distance, indicating a tolerant mechanism for stereoscopic processing by the human neural system.
Short-term measurement of N2O emissions from sheep-grazed pasture receiving increasing rates of fertiliser nitrogen in Otago, New Zealand
Authors: Letica S. A. , de Klein C. A. M. , Hoogendoorn C. J. , Tillman R. W. , Littlejohn R. P. , Rutherford A. J.
Published: December 2009

The purpose of this short-term study was to investigate the effect of increasing fertiliser nitrogen (N) application rates on nitrous oxide (N2O) emissions over the late winter/early spring period from sheep-grazed pasture in Otago rolling hill country. We measured N2O gas emissions from plots on a mottled Fragic Pallic hill soil receiving 0, 100 and 500 kg N/ha.year for 2 years. Plots were sampled weekly for 10 weeks over the 2006 winter/spring period using a static chamber method. Increased N fertiliser rate and the attendant increase in stocking rate significantly increased total N2O emissions (P < 0.05). Total N2O emissions for the measurement period were estimated to be 0.08, 0.13 and 1.36 kg N2O-N/ha (s.e.m, 0.1, 0.18 and 0.45) for the 0, 100 and 500 N treatments, respectively. Our results suggest that high application rates of fertiliser N (i.e. 500 kg N/ha.year) and attendant increased stocking rates may significantly increase emissions of N2O even in dry winter/spring conditions in Otago rolling hill country. These results will assist in the development of best management guidelines for reducing N2O emissions from fertiliser N in hill country.
Contact metamorphism, halocarbons, and environmental crises of the past
Authors: Svensen Henrik , Schmidbauer Norbert , Roscher Marco , Stordal Frode , Planke Sverre
Published: December 2009

Environmental context. What caused the biggest known mass extinction on Earth ~252 million years ago? A possible killer mechanism was the release of specific gases into the atmosphere, which eventually led to destruction of the ozone layer. This is now supported by new laboratory experiments in which ozone-destructing gases were generated when heating rocks from East Siberia (Russia) – reconstructing what happened naturally in Siberia during explosive gas eruptions 252 million years ago.
Abstract. What triggered the largest know mass extinction at the Permian–Triassic boundary 252 million years ago, when 95% of the species in the oceans disappeared? New geological data suggest that eruptions of carbon (CH4, CO2) and halocarbon (CH3Cl and CH3Br) gases from the vast sedimentary basins of east Siberia could have triggered a period with global warming (5°–10°C) and terrestrial mass extinction. The gases were generated during contact metamorphism of sedimentary rocks around 1200°C hot igneous intrusions. One of the suggested end-Permian extinction mechanisms is the extreme ultraviolet radiation (UV-B) caused by a prolonged destruction of stratospheric ozone induced by the emitted halocarbons. This hypothesis is supported by a new set of experiments, where natural rock salt samples from Siberia were heated to 275°C. Among the gases generated during heating are methyl chloride (CH3Cl) and methyl bromide (CH3Br). These findings open up new possibilities for investigating ancient environmental crises.
Effects of multiple disturbances in seagrass meadows: shading decreases resilience to grazing
Authors: Eklöf Johan S. , McMahon Kathryn , Lavery Paul S.
Published: December 2009

Ecosystem shifts are often associated with multiple disturbances, but limited knowledge on the mechanisms involved hampers management. This study investigated how short-term shading affected the resilience of the seagrass Halophila ovalis to grazing by black swans (Cygnus atratus) – a historically dominant grazer currently recovering from hunting and habitat loss – in south-western Australian estuaries, using field surveys and a grazing-shading experiment. Black swans were heterogeneously distributed and, in a high-density site, consumed 23% of seagrass production. Seagrasses recovered rapidly from a single disturbance (i.e. short-term shading or grazing), even though shading alone halved carbohydrate content. When seagrasses were exposed to both disturbances, recovery depended on the type of grazing; where grazing was confined to leaves, leaf densities recovered within 3 weeks, but where grazing was on both leaves and rhizomes there was no recovery. Shading increased the frequency of apex initiation, as did rhizome grazing, but only if the plants had not been shaded. This indicates that shading alters the flow of energy needed to produce apices and leaves following disturbance on rhizomes. Based on the historical swan densities and continuing recurring phytoplankton blooms, management actions reintroducing swans without controlling algal blooms could have an on impact seagrass resilience and associated organisms.
NMR reveals pathway for ferric mineral precursors to the central cavity of ferritin
Authors: Turano Paola , Lalli Daniela , Felli Isabella C. , Theil Elizabeth C. , Bertini Ivano
Published: December 2009

Ferritin is a multimeric nanocage protein that directs the reversible biomineralization of iron. At the catalytic ferroxidase site two iron(II) ions react with dioxygen to form diferric species. In order to study the pathway of iron(III) from the ferroxidase site to the central cavity a new NMR strategy was developed to manage the investigation of a system composed of 24 monomers of 20 kDa each. The strategy is based on
13
C-
13
C solution NOESY experiments combined with solid-state proton-driven
13
C-
13
C spin diffusion and 3D coherence transfer experiments. In this way, 75% of amino acids were recognized and 35% sequence-specific assigned. Paramagnetic broadening, induced by iron(III) species in solution
13
C-
13
C NOESY spectra, localized the iron within each subunit and traced the progression to the central cavity. Eight iron ions fill the 20-Å-long iron channel from the ferrous/dioxygen oxidoreductase site to the exit into the cavity, inside the four-helix bundle of each subunit, contrasting with short paths in models. Magnetic susceptibility data support the formation of ferric multimers in the iron channels. Multiple iron channel exits are near enough to facilitate high concentration of iron that can mineralize in the ferritin cavity, illustrating advantages of the multisubunit cage structure.
Janus-faced Enzymes Yeast Tgl3p and Tgl5p Catalyze Lipase and Acyltransferase Reactions
Authors: Rajakumari Sona , Daum Günther
Published: December 2009

In the yeast, mobilization of triacylglycerols (TAGs) is facilitated by the three TAG lipases Tgl3p, Tgl4p, and Tgl5p. Motif search analysis, however, indicated that Tgl3p and Tgl5p do not only contain the TAG lipase motif GXSXG but also an H-(X)4-D acyltransferase motif. Interestingly, lipid analysis revealed that deletion of TGL3 resulted in a decrease and overexpression of TGL3 in an increase of glycerophospholipids. Similar results were obtained with TGL5. Therefore, we tested purified Tgl3p and Tgl5p for acyltransferase activity. Indeed, both enzymes not only exhibited lipase activity but also catalyzed acylation of lysophosphatidylethanolamine and lysophosphatidic acid, respectively. Experiments using variants of Tgl3p created by site-directed mutagenesis clearly demonstrated that the two enzymatic activities act independently of each other. We also showed that Tgl3p is important for efficient sporulation of yeast cells, but rather through its acyltransferase than lipase activity. In summary, our results demonstrate that yeast Tgl3p and Tgl5p play a dual role in lipid metabolism contributing to both anabolic and catabolic processes.
Acute Surgical Anemia Influences the Cardioprotective Effects of β-Blockade
Authors: Beattie W Scott , Wijeysundera Duminda N. , Karkouti Keyvan , McCluskey Stuart , Tait Gordon , Mitsakakis Nicholas , Hare Gregory M. T.
Published: December 2009

Background

Despite decreasing cardiac events, perioperative beta-blockade also increases perioperative stroke and mortality. Major bleeding and/or hypotension are independently associated with these outcomes. To investigate the hypothesis that beta-blockade limits the cardiac reserve to compensate for acute surgical anemia, the authors examined the relationship between cardiac events and acute surgical anemia in patients with and without beta-blockade.

Methods

The records of all noncardiac, nontransplant surgical patients between March 2005 and June 2006 were retrospectively retrieved. The primary outcome was a composite that comprised myocardial infarction, nonfatal cardiac arrest, and in-hospital mortality (major adverse cardiac event). The lowest recorded hemoglobin in the first 3 days defined nadir hemoglobin. Propensity scores estimating the probability of receiving a perioperative beta-blocker were used to match (1:1) patients who did or did not receive beta-blockers postoperatively. The relationship between nadir hemoglobin and major adverse cardiac event was then assessed.

Results

This analysis identified 4,387 patients in whom nadir hemoglobin could be calculated; 1,153 (26%) patients were administered beta-blockers within the first 24 h of surgery. Propensity scores created 827 matched pairs that were well balanced for all measured confounders. Major adverse cardiac event occurred in 54 (6.5%) beta-blocked patients and in 25 (3.0%) beta-blocker naive patients (relative risk 2.38; 95% CI 1.43-3.96; P = 0.0009). The restricted cubic spline relationship demonstrated that this difference was restricted to those patients in whom the hemoglobin decrease exceeded 35% of the baseline value.

Conclusions

beta-Blocked patients do not seem to tolerate surgical anemia when compared with patients who are naive to beta-blockers. Prospective studies are required to validate these findings.
Impact of Virtual Imaging Procedures on Treatment Strategies in Children With Hepatic Vascular Malformations
Authors: Fuchs Jörg , Warmann Steven W , Sieverding Ludger , Haber Hans P , Schäfer Jürgen , Seitz Guido , Hofbeck Michael , Bourquain Holger , Peitgen Heinz O
Published: December 2009

Objectives:

Virtual imaging procedures have only rarely been analyzed in pediatric populations. We evaluated the role of CT‐based virtual surgery planning in pediatric patients experiencing hepatic vascular malformations (HVM).

Methods:

We analyzed 12 children with complex hepatic vascular malformations. All of the children received multislice CT scans with contrast medium followed by virtual 3‐dimensional reconstructions using the software assistants MeVis LiverAnalyzer and MeVis LiverExplorer. The impact on treatment planning and the correspondence to clinical findings was assessed.

Results:

Highest accuracies of virtual data were found in cases of intrahepatic portocaval shunt and persistent ductus venosus. Here, virtual data revealed congenital vascular conditions, which were not always seen using standard imaging diagnostics. In some patients with portalvenous thrombosis, virtual imaging provided important contributions to determining the feasibility of different shunt procedures. However, in some patients experiencing portalvenous thrombosis or liver diffuse hemangioma, virtual methods were not as accurate as standard diagnostic procedures. Nevertheless, these tools facilitated simultaneous and continuous illustrations of the different vascular systems.

Conclusions:

Virtual imaging and planning procedures had an important impact on treatment strategies and outcomes in children with HVM. Their use as standard diagnostic tools in selected cases of HVM should be considered.
Infant Formula Supplementation With Long‐chain Polyunsaturated Fatty Acids Has No Effect on Bayley Developmental Scores at 18 Months of Age—IPD Meta‐analysis of 4 Large Clinical Trials
Authors: Beyerlein Andreas , Hadders‐Algra Mijna , Kennedy Katherine , Fewtrell Mary , Singhal Atul , Rosenfeld Eva , Lucas Alan , Bouwstra Hylco , Koletzko Berthold , von Kries Rüdiger
Published: December 2009

Objectives:

To find out whether supplementation of formula milk by long‐chain polyunsaturated fatty acids (LCPUFA) affects neurodevelopment at 18 months of age in term or preterm infants by an individual patient data (IPD) meta‐analysis.

Materials and Methods:

Data of 870 children from 4 large randomised clinical trials for formula milk with and without LCPUFAs allowed for assessing the effect of LCPUFA with adjustment for potential confounders and extensive subgroup analysis on prematurity, LCPUFA source, and dosage. Any additional clinical trials examining the effect of LCPUFA supplementation on Bayley Scales of Infant Development at 18 months were regarded as relevant. Two relevant studies were identified by MEDLINE, but were not available to us. An IPD meta‐analysis was performed with subgroup analyses by preterm delivery, very low birth weight (<1500 g), trials with higher amounts of docosahexaenoic acid (DHA) and arachidonic acid (AA), and specific sources of LCPUFA. The sample size of 870 children was sufficient to detect clinically relevant differences in Bayley Scales even in subgroups.

Results:

There were no significant differences in mental or psychomotor developmental indexes between LCPUFA‐supplemented and control groups for all children or in subgroups. This was confirmed with adjustment for the possible confounders: sex, gestational age, birth weight, maternal age, and maternal smoking. The adjusted mean differences in mental developmental index and psychomotor developmental index for all of the children were −0.8 (95% confidence interval −2.8 to 1.2) and −1.0 (−2.7 to 0.7), respectively.

Conclusions:

These data based on considerable sample size provide substantial evidence that LCPUFA supplementation of infant formula does not have a clinically meaningful effect on the neurodevelopment as assessed by Bayley scores at 18 months. Inclusion of all relevant data should not have led to differing conclusions except, possibly, for very‐low‐birth‐weight infants.
Budd‐Chiari Syndrome in Children: Experience With Therapeutic Radiological Intervention
Authors: Nagral Aabha , Hasija Rachana P , Marar Shaji , Nabi Fazal
Published: December 2009

Objectives:

Budd‐Chiari syndrome (BCS) in children is not uncommon. Published literature on therapy for this condition is scarce. We therefore attempted radiological interventions in these patients to determine their efficacy and safety.

Patients and Methods:

Fourteen of 16 children with a median age of 22 months diagnosed as having BCS were subjected to an inferior vena cava/hepatic venogram with the aim to establish a normal antegrade flow in at least 1 hepatic vein (HV).

Results:

A normal antegrade flow in at least 1 of the HVs could be established in 11 children. Three patients had angioplasty of the HV (vein size ≤4 mm), 2 underwent HV stent placements (vein size ≥5 mm), and 6 had transjugular intrahepatic porta systemic shunt ([TIPSS] total occlusion of all 3 HVs or veno‐occlusive disease). The youngest child undergoing a successful stenting was 7 months of age and the child undergoing TIPSS was 3 years of age. One patient had reversal of fulminant liver failure following a successful TIPSS. Postprocedure, 2 patients developed reversible encephalopathy and 1 had a neck hematoma. There was no procedure‐related mortality. The procedure was successful in both patients with stenting (100%), 5 of the 6 patients with TIPSS (80%), and only 1 of the 4 patients (25%) with angioplasty. The median follow‐up was 31 months.

Conclusions:

Radiological therapeutic intervention is feasible and safe in children with BCS. The overall results of stenting/TIPSS are better than with angioplasty; however, long‐term results of these interventions need to be evaluated.
Rising Incidence of Inflammatory Bowel Disease Among Children: A 12‐year Study
Authors: Malaty Hoda M , Fan Xiaolin , Opekun Antone R , Thibodeaux Carolyn , Ferry George D
Published: December 2009

Objective:

Data suggest an increase in the incidence of pediatric inflammatory bowel disease (IBD). We examined the trend of the incidence of IBD in children.

Patients and Methods:

A retrospective investigation was conducted on a cohort of children diagnosed with IBD between 1991 and 2002 who were registered in the IBD center at Texas Children's Hospital. The diagnosis of IBD was based on clinical, radiological, endoscopic, and histological examinations.

Results:

There were 272 children eligible for the analysis; 56% diagnosed with Crohn disease (CD), 22% with ulcerative colitis (UC), and 22% with indeterminate colitis. The male‐to‐female ratio was 1.2:1 in CD, 0.6:1 in UC, and 0.8:1 in indeterminate colitis. From 1991 to 2002, the incidence rate has doubled from 1.1/100,000/year (95% confidence interval [CI] 0.85–1.36) to 2.4/1001,000/year (95% CI 2.10–2.77). This trend was valid for CD but not for UC. Whites had higher incidence rate of IBD than African Americans or Hispanics: 4.15/100,000/year (95% CI 3.48–4.82) versus 1.83/100,000/year (95% CI 1.14–2.51), and 0.61/100,000/year (95% CI 0.33–0.89), respectively. African Americans were predominantly diagnosed with CD.

Conclusions:

The results demonstrate the rising incidence of IBD among children with evidence of more CD than UC. Recognition of these results will have important implications for diagnosis and management of IBD in children.
DNA barcodes for 1/1000 of the animal kingdom
Authors: Hebert Paul D. N. , deWaard Jeremy R. , Landry Jean-François
Published: December 2009

This study reports DNA barcodes for more than 1300 Lepidoptera species from the eastern half of North America, establishing that 99.3 per cent of these species possess diagnostic barcode sequences. Intraspecific divergences averaged just 0.43 per cent among this assemblage, but most values were lower. The mean was elevated by deep barcode divergences (greater than 2%) in 5.1 per cent of the species, often involving the sympatric occurrence of two barcode clusters. A few of these cases have been analysed in detail, revealing species overlooked by the current taxonomic system. This study also provided a large-scale test of the extent of regional divergence in barcode sequences, indicating that geographical differentiation in the Lepidoptera of eastern North America is small, even when comparisons involve populations as much as 2800 km apart. The present results affirm that a highly effective system for the identification of Lepidoptera in this region can be built with few records per species because of the limited intra-specific variation. As most terrestrial and marine taxa are likely to possess a similar pattern of population structure, an effective DNA-based identification system can be developed with modest effort.
Multiple signals and male spacing affect female preference at cocktail parties in treefrogs
Authors: Richardson Christina , Lengagne Thierry
Published: December 2009

Effective acoustic communication in the face of intense conspecific background noise constitutes a constant sensory challenge in chorusing and colonial species. An evolutionary approach suggests that behavioural and environmental constraints in these species should have shaped signal design and signalling behaviour to enable communication in noisy conditions. This could be attained both through the use of multicomponent signals and through short-term adjustments in the spatial separation of calling males. We investigated these two hypotheses in a chorusing anuran, the hylidHyla arborea, through a series of phonotaxis experiments conducted within a six-speaker arena in a high background noise situation, by presenting females with male calls containing either single or multiple attractive call components, and by modifying distances between speakers. We found that female ability to discriminate attractive calls increased when several attractive call components were available, providing novel evidence that the use of multicomponent signals enhances communication in complex acoustic conditions. Signal discrimination in females also improved with speaker separation, demonstrating that within natural choruses, spatial unmasking conditioned by male density and spatial separation probably improves female discrimination of competing males. Implications of these results for the accuracy of mate choice within choruses are discussed.