bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature dependent properties of InSb and InAs nanowire field-effect transistors
Authors: Nilsson Henrik A. , Caroff Philippe , Thelander Claes , Lind Erik , Karlström Olov , Wernersson Lars-Erik
Published: April 2010

We present temperature dependent electrical measurements on InSb and InAs nanowire field-effect transistors (FETs). The FETs are fabricated from InAs/InSb heterostructure nanowires, where one complete transistor is defined within each of the two segments. Both the InSb and the InAs FETs are n-type with good current saturation and low voltage operation. The off-current for the InSb FET shows a strong temperature dependence, which we attribute to a barrier lowering due to an increased band-to-band tunneling in the drain part of the channel.
Theoretical investigation of optical polarization properties in Al-rich AlGaN quantum wells with various substrate orientations
Authors: Yamaguchi A. Atsushi
Published: April 2010

The optical polarization properties of Al-rich AlGaN thin quantum wells on AlN substrates with various substrate orientations are numerically calculated using a 6×6 k⋅p Hamiltonian. The calculation results show that the predominant polarization direction abruptly switches from the in-plane direction to the c-axis direction at an Al composition of ∼0.76 in quantum wells on c-plane substrates. It is also shown that the polarization characteristics drastically change by small inclination of the substrates due to valence band mixing effects. It is found that the use of the vicinal substrates as well as semipolar and nonpolar substrates could be beneficial in improving optical device performance.
Defining spatial genetic structure and management units for vulnerable koala (Phascolarctos cinereus) populations in the Sydney region, Australia
Authors: Lee Tristan , Zenger Kyall R. , Close Robert L. , Jones Marilyn , Phalen David N.
Published: April 2010

Context. Mammal populations around the world are increasingly threatened with population fragmentation because of loss of habitat or barriers to gene flow. The investigation of koala populations in the Sydney region not only provides valuable information about this vulnerable species, but also serves as a model for other species that have suffered major rapid declines in population size, and are now recovering in fragmented habitat. The peri-urban study region allows investigation of the impact of landscape features such as major roads and housing developments on koala gene flow. Aims. Animals originating from four geographic sampling areas around Sydney, New South Wales, Australia, were examined to determine population structure and gene flow and to identify barriers to gene flow and management units. Methods. The present study examined 12 microsatellite loci and used Bayesian assignment methods and genic frequency analysis methods to identify demographically separate populations and barriers to gene flow between those populations. Key results. Three discrete populations were resolved, with all displaying moderate to high levels of genetic differentiation among them (θ = 0.141–0.224). The allelic richness and heterozygosity of the Blue Mountains population (A = 6.46, HO = 0.66) is comparable to the highest diversity found in any koala population previously investigated. However, considerably lower genetic diversity was found in the Campbelltown population (A = 3.17, HO = 0.49), which also displayed evidence of a recent population bottleneck (effective population size estimated at 16–21). Conclusions. Animals separated by a military reserve were identified as one population, suggesting that the reserve maintains gene flow within this population. By contrast, strong differentiation of two geographically close populations separated by several potential barriers to gene flow suggested these land-use features pose barriers to gene flow. Implications. Implications of these findings for management of koala populations in the Greater Sydney region are discussed. In particular, the need to carefully consider the future of a military reserve is highlighted, along with possible solutions to allow gene flow across the proposed barrier regions. Because these are demographically separate populations, specific management plans tailored to the needs of each population will need to be formulated.
Risk-based surveillance of avian influenza in Australia's wild birds
Authors: Tracey John P.
Published: April 2010

Context. The epidemiology of avian influenza and the ecology of wild birds are inextricably linked. An understanding of both is essential in assessing and managing the risks of highly pathogenic avian influenza (HPAI). Aims. This project investigates the abundance, movements and breeding ecology of Australia’s Anseriformes in relation to the prevalence of low-pathogenicity avian influenza (LPAI) and provides risk profiles to improve the efficiency and relevance of wild-bird surveillance. Methods. Generalised linear models and analysis of variance were used to examine the determinants of Anseriformes abundance and movements in Australia, and the observed prevalence of LPAI in Australia (n = 33 139) and overseas (n = 93 344). Risk profiles were developed using poultry density, estimated LPAI prevalence, the abundance of Anseriformes, and the probability of Anseriformes moving from areas of HPAI epizootics. Key results. Analysis of Australian wild-bird surveillance data strongly supports other studies that have found the prevalence of LPAI in wild birds to be much lower (1%) in Australia than that in other countries (4.7%). LPAI prevalence was highly variable among sampling periods and locations and significantly higher in dabbling ducks than in other functional groups. Trends in Anseriformes movements, abundance and breeding are also variable, and correlated with rainfall, which could explain low prevalence and the failure to detect seasonal differences in LPAI in wild birds. Virus prevalence of faecal samples was significantly lower, whereas collecting faecal samples was 3–5 times less expensive and logistically simpler, than that of cloacal samples. Overall priority areas for on-going surveillance are provided for Australia. Conclusions. Previous surveillance has occurred in high-priority areas, with the exception of Mareeba (North Queensland), Brisbane and Darwin, and has provided valuable information on the role of wild birds in maintaining avian influenza viruses. However, several practical considerations need to be addressed for future surveillance. Implications. Long-term surveillance studies in wild birds in priority areas are required, which incorporate information on bird abundance, age, behaviour, breeding and movements, particularly for dabbling ducks. This is important to validate trends of LPAI prevalence, in understanding the main determinants for virus spread and persistence, and in predicting and managing future epizootics of HPAI in Australia.
Predation on toxic cane toads (Bufo marinus) may imperil bluetongue lizards (Tiliqua scincoides intermedia, Scincidae) in tropical Australia
Authors: Price-Rees Samantha J. , Brown Gregory P. , Shine Richard
Published: April 2010

Context. Detecting ecological impacts of invasive species can be extremely difficult. Even major population declines may be undetectable without extensive long-term data if the affected taxon is rare and/or difficult to census, and exhibits stochastic variation in abundance as a result of other factors. Our data suggest such a situation in an iconic Australian reptile species, the bluetongue lizard. Originally restricted to Central and South America, cane toads (Bufo marinus) are rapidly spreading through tropical Australia. Most native predators have no evolutionary history of exposure to the toads’ distinctive chemical defences (bufadienolides), and many varanid lizards, elapid snakes, crocodiles and marsupials have been killed when they have attempted to consume toads. Aims. Scincid lizards have not been considered vulnerable to toad invasion; however, one lineage (the bluetongues, genus Tiliqua) consists of large omnivores that may be affected. Our field and laboratory research aimed to elucidate this concern. Methods. Nightly surveys for bluetongue lizards (Tiliqua scincoides intermedia) and cane toads were conducted along two adjacent roadways on the Adelaide River floodplain of the Northern Territory. Scent discrimination trials in the laboratory assessed lizard responses to chemical cues from three food types (native frogs, cane toads and ‘preferred foods’) by counting tongue-flicks and biting elicited by cotton swabs. A subset of lizards was presented with live toads. Key results. Numbers of bluetongues encountered during standardised field surveys in the Darwin region declined soon after toads arrived, and we have not recorded a single lizard for the last 20 months. In the laboratory, foraging responses of bluetongues were as intense to cane-toad scent as to the scent of native frogs, and many of the lizards we tested attempted to consume toads, and were poisoned as a result. Conclusions and implications. The population decline of bluetongues in this region appears to have been the direct result of fatal ingestion of toxic cane toads. Our studies thus add a scincid lizard species to the list of native Australian predators imperilled by cane-toad invasion, and point to the difficulty of detecting invader impact even for an iconic species in a system subject to detailed survey work.
Picante: R tools for integrating phylogenies and ecology
Authors: Kembel Steven W. , Cowan Peter D. , Helmus Matthew R. , Cornwell William K. , Morlon Helene , Ackerly David D. , Blomberg Simon P. , Webb Campbell O.
Published: April 2010

Summary: Picante is a software package that provides a comprehensive set of tools for analyzing the phylogenetic and trait diversity of ecological communities. The package calculates phylogenetic diversity metrics, performs trait comparative analyses, manipulates phenotypic and phylogenetic data, and performs tests for phylogenetic signal in trait distributions, community structure and species interactions.

Availability: Picante is a package for the R statistical language and environment written in R and C, released under a GPL v2 open-source license, and freely available on the web (http://picante.r-forge.r-project.org) and from CRAN (http://cran.r-project.org).

Contact:  skembel@uoregon.edu
Voyage of the argonauts in the pelagic realm: physiological and behavioural ecology of the rare paper nautilus, Argonauta nouryi
Authors: Rosa Rui , Seibel Brad A.
Published: April 2010

Rosa, R., and Seibel, B. A. 2010. Voyage of the argonauts in the pelagic realm: physiological and behavioural ecology of the rare paper nautilus, Argonauta nouryi. – ICES Journal of Marine Science, 67: 1494–1500. The metabolic demands of a rare paper nautilus, Argonauta nouryi, in the eastern tropical Pacific (ETP) are evaluated. After adjusting for temperature and size, the rates of oxygen consumption and of aerobic and anaerobic metabolic potential (as evidenced by citrate synthase and octopine dehydrogenase activities, respectively) of A. nouryi were much higher than those in holopelagic octopods that exhibit float-and-wait predation strategies. In fact, the rates were similar to those found in small epipelagic squids and benthic octopods. The critical oxygen partial pressure was 4.9 kPa at 20°C, suggesting that the strong oxygen minimum layer found at intermediate depths in the ETP may constrain the vertical distribution of A. nouryi to the upper few metres of the water column. We also report the occurrence of a chain of shelled females at the surface, in which each animal was attached, as if on the benthos, to the next individual in the chain. Although it may constitute an effective strategy to increase the rates of mate encounter in the vast open ocean, there may be an important ecological trade-off for such behaviour, namely the increase in visibility at the surface with concomitant attraction of predators.
The surprising diversity of clostridial hydrogenases: a comparative genomic perspective
Authors: Calusinska Magdalena , Happe Thomas , Joris Bernard , Wilmotte Annick
Published: April 2010

Among the large variety of micro-organisms capable of fermentative hydrogen production, strict anaerobes such as members of the genus Clostridium are the most widely studied. They can produce hydrogen by a reversible reduction of protons accumulated during fermentation to dihydrogen, a reaction which is catalysed by hydrogenases. Sequenced genomes provide completely new insights into the diversity of clostridial hydrogenases. Building on previous reports, we found that [FeFe] hydrogenases are not a homogeneous group of enzymes, but exist in multiple forms with different modular structures and are especially abundant in members of the genus Clostridium. This unusual diversity seems to support the central role of hydrogenases in cell metabolism. In particular, the presence of multiple putative operons encoding multisubunit [FeFe] hydrogenases highlights the fact that hydrogen metabolism is very complex in this genus. In contrast with [FeFe] hydrogenases, their [NiFe] hydrogenase counterparts, widely represented in other bacteria and archaea, are found in only a few clostridial species. Surprisingly, a heteromultimeric Ech hydrogenase, known to be an energy-converting [NiFe] hydrogenase and previously described only in methanogenic archaea and some sulfur-reducing bacteria, was found to be encoded by the genomes of four cellulolytic strains: Clostridum cellulolyticum, Clostridum papyrosolvens, Clostridum thermocellum and Clostridum phytofermentans.
Two regulatory elements required for enhancing ospA expression in Borrelia burgdorferi grown in vitro but repressing its expression during mammalian infection
Authors: Xu Qilong , McShan Kristy , Liang Fang Ting
Published: April 2010

During cycling between the tick vector and a mammal, the Lyme disease spirochaete Borrelia burgdorferi must coordinate expression of outer-surface proteins (Osps) A and B to quickly respond to environmental changes. The pathogen abundantly produces OspA/B in the tick, but represses their expression during mammalian infection. This paper reports a regulatory structure, consisting of two sequences flanking the ospAB promoter, that is required for enhancing ospA expression in B. burgdorferi grown in vitro, but repressing its expression during murine infection. Deletion or replacement of either the upstream or downstream sequence of the ospAB promoter caused a significant decrease in ospA expression in vitro, but a dramatic increase during murine infection. Fusion of either sequence with the flaB reporter promoter led to increased expression of an ospA reporter gene in vitro, but a decrease in the murine host. Furthermore, simultaneous fusion of both sequences with the reporter promoter showed a synergistic effect in enhancing expression of the ospA reporter in vitro, but repressing its expression during murine infection. Taken together, the results demonstrate that the regulatory structure functions oppositely in the two different environments and potentially provides B. burgdorferi with a molecular mechanism to quickly adapt to the distinct environments during its enzootic life cycle.
Structural and functional characterization of the transcriptional repressor CsoR from Thermus thermophilus HB8
Authors: Sakamoto Keiko , Agari Yoshihiro , Agari Kazuko , Kuramitsu Seiki , Shinkai Akeo
Published: April 2010

The TTHA1719 gene from Thermus thermophilus HB8 encodes an orthologue of the copper-sensing transcriptional repressor CsoR. X-ray crystal structure analysis of T. thermophilus CsoR indicated that it forms a homotetramer. The structures of the CsoR monomer and dimer are similar to those of Mycobacterium tuberculosis CsoR. In the absence of copper ions, T. thermophilus CsoR bound to the promoter region of the copper-sensitive operon copZ-csoR-copA, which encodes the copper chaperone CopZ, CsoR and the copper efflux P-type ATPase CopA, to repress their expression, while in the presence of approximately an equal amount of copper ion, CsoR was released from the DNA, to allow expression of the downstream genes. Both Cu(II) and Cu(I) ions could bind CsoR, and were effective for transcriptional derepression. Additionally, CsoR could also sense various other metal ions, such as Zn(II), Ag(I), Cd(II) and Ni(II), which led to transcriptional derepression. The copper-binding motif of T. thermophilus CsoR contains C-H-H, while those of most orthologues contain C-H-C. The X-ray crystal structure of T. thermophilus CsoR suggests that a histidine residue in the N-terminal domain is also involved in metal-ion binding; that is, the binding motif could be H-C-H-H, like that of Escherichia
coli RcnR, which binds Ni(II)/Co(II). The non-conserved H70 residue in the metal-binding motif of T. thermophilus CsoR is important for its DNA-binding affinity and metal-ion responsiveness.
Biofilm formation is not required for early-phase transmission of Yersinia pestis
Authors: Vetter Sara M. , Eisen Rebecca J. , Schotthoefer Anna M. , Montenieri John A. , Holmes Jennifer L. , Bobrov Alexander G. , Bearden Scott W. , Perry Robert D. , Gage Kenneth L.
Published: April 2010

Early-phase transmission (EPT) is a recently described model of plague transmission that explains the rapid spread of disease from flea to mammal host during an epizootic. Unlike the traditional blockage-dependent model of plague transmission, EPT can occur when a flea takes its first blood meal after initially becoming infected by feeding on a bacteraemic host. Blockage of the flea gut results from biofilm formation in the proventriculus, mediated by the gene products found in the haemin storage (hms) locus of theYersinia pestischromosome. Although biofilms are required for blockage-dependent transmission, the role of biofilms in EPT has yet to be determined. An artificial feeding system was used to feedXenopsylla cheopisandOropsylla montanarat blood spiked with the parentalY. pestisstrain KIM5(pCD1)+, two different biofilm-deficient mutants (ΔhmsT, ΔhmsR), or a biofilm-overproducer mutant (ΔhmsP). Infected fleas were then allowed to feed on naïve Swiss Webster mice for 1–4 days after infection, and the mice were monitored for signs of infection. We also determined the bacterial loads of each flea that fed upon naïve mice. Biofilm-defective mutants transmitted fromX. cheopisandO. montanaas efficiently as the parent strain, whereas the EPT efficiency of fleas fed the biofilm-overproducing strain was significantly less than that of fleas fed either the parent or a biofilm-deficient strain. Fleas infected with a biofilm-deficient strain harboured lower bacterial loads 4 days post-infection than fleas infected with the parent strain. Thus, defects in biofilm formation did not prevent flea-borne transmission ofY. pestisin our EPT model, although biofilm overproduction inhibited efficient EPT. Our results also indicate, however, that biofilms may play a role in infection persistence in the flea.
Derepression of Polycomb targets during pancreatic organogenesis allows insulin-producing beta-cells to adopt a neural gene activity program
Authors: van Arensbergen Joris , García-Hurtado Javier , Moran Ignasi , Maestro Miguel Angel , Xu Xiaobo , Van de Casteele Mark , Skoudy Anouchka L. , Palassini Matteo , Heimberg Harry , Ferrer Jorge
Published: April 2010

The epigenome changes that underlie cellular differentiation in developing organisms are poorly understood. To gain insights into how pancreatic beta-cells are programmed, we profiled key histone methylations and transcripts in embryonic stem cells, multipotent progenitors of the nascent embryonic pancreas, purified beta-cells, and 10 differentiated tissues. We report that despite their endodermal origin, beta-cells show a transcriptional and active chromatin signature that is most similar to ectoderm-derived neural tissues. In contrast, the beta-cell signature of trimethylated H3K27, a mark of Polycomb-mediated repression, clusters with pancreatic progenitors, acinar cells and liver, consistent with the epigenetic transmission of this mark from endoderm progenitors to their differentiated cellular progeny. We also identified two H3K27 methylation events that arise in the beta-cell lineage after the pancreatic progenitor stage. One is a wave of cell-selective de novo H3K27 trimethylation in non-CpG island genes. Another is the loss of bivalent and H3K27me3-repressed chromatin in a core program of neural developmental regulators that enables a convergence of the gene activity state of beta-cells with that of neural cells. These findings reveal a dynamic regulation of Polycomb repression programs that shape the identity of differentiated beta-cells.
A Bioinformatics Approach to the Identification, Classification, and Analysis of Hydroxyproline-Rich Glycoproteins
Authors: Showalter Allan M. , Keppler Brian , Lichtenberg Jens , Gu Dazhang , Welch Lonnie R.
Published: April 2010

Hydroxyproline-rich glycoproteins (HRGPs) are a superfamily of plant cell wall proteins that function in diverse aspects of plant growth and development. This superfamily consists of three members: hyperglycosylated arabinogalactan proteins (AGPs), moderately glycosylated extensins (EXTs), and lightly glycosylated proline-rich proteins (PRPs). Hybrid and chimeric versions of HRGP molecules also exist. In order to “mine” genomic databases for HRGPs and to facilitate and guide research in the field, the BIO OHIO software program was developed that identifies and classifies AGPs, EXTs, PRPs, hybrid HRGPs, and chimeric HRGPs from proteins predicted from DNA sequence data. This bioinformatics program is based on searching for biased amino acid compositions and for particular protein motifs associated with known HRGPs. HRGPs identified by the program are subsequently analyzed to elucidate the following: (1) repeating amino acid sequences, (2) signal peptide and glycosylphosphatidylinositol lipid anchor addition sequences, (3) similar HRGPs via Basic Local Alignment Search Tool, (4) expression patterns of their genes, (5) other HRGPs, glycosyl transferase, prolyl 4-hydroxylase, and peroxidase genes coexpressed with their genes, and (6) gene structure and whether genetic mutants exist in their genes. The program was used to identify and classify 166 HRGPs from Arabidopsis (Arabidopsis thaliana) as follows: 85 AGPs (including classical AGPs, lysine-rich AGPs, arabinogalactan peptides, fasciclin-like AGPs, plastocyanin AGPs, and other chimeric AGPs), 59 EXTs (including SP5 EXTs, SP5/SP4 EXTs, SP4 EXTs, SP4/SP3 EXTs, a SP3 EXT, “short” EXTs, leucine-rich repeat-EXTs, proline-rich extensin-like receptor kinases, and other chimeric EXTs), 18 PRPs (including PRPs and chimeric PRPs), and AGP/EXT hybrid HRGPs.
Effects of UV Radiation and Diet on Polyunsaturated Fatty Acids in the Skin, Ocular Tissue and Dorsal Muscle of Atlantic Salmon (Salmo salar) Held in Outdoor Rearing Tanks
Authors: Arts Michael T. , Browman Howard I. , Jokinen Ilmari E. , Skiftesvik Anne Berit
Published: April 2010

The effect of UV radiation (UVR) on juvenile Atlantic salmon (Salmo salar) was assessed by measuring the fatty acid (FA) profiles of muscle, dorsal and ventral skin, and ocular tissues following 4‐month long exposures to four different UVR treatments in outdoor rearing tanks. Fish were fed two different diets (Anchovy‐ and Herring‐oil based) that differed in polyunsaturated fatty acid (PUFA) concentrations. Anchovy‐fed salmon had higher concentrations of ALA (alpha‐linoleic acid; 18:3n‐3), EPA (eicosapentaenoic acid; 20:5n‐3) and DPA (docosapentaenoic acid, 22:5n‐3) in their muscle tissues than fish fed the Herring feed. Fish subjected to enhanced UVB levels had higher concentrations of LIN (linolenic acid, 18:2n‐6) and ALA, total omega‐6 FA and SAFA (saturated fatty acids) in their tissues compared with fish in reduced UV treatments. Concentrations of ALA, LIN, GLA (gamma‐linolenic acid; 18:3n‐6), EPA, PUFA and total FA were higher in ventral skin of fish exposed to enhanced UVB compared with fish in reduced UV treatments. Salmon exposed to reduced UV weighed more per‐unit‐length than fish exposed to ambient sunlight. The FA profiles suggest that fish exposed to UV radiation were more quiescent than fish in the reduced UV treatments resulting in a buildup of catabolic substrates.
Effect of midazolam on memory: a study of process dissociation procedure and functional magnetic resonance imaging
Authors: Tian S. Y. , Zou L. , Quan X. , Zhang Y. , Xue F. S. , Ye T. H.
Published: April 2010

To assess the effects of midazolam on explicit and implicit memories, 12 volunteers were randomly divided into the two groups: one with an Observer’s Assessment of Alertness/Sedation score of 3 (mild sedation) and one with a score of 1 (deep sedation). Blood oxygen‐level‐dependent functional magnetic resonance imaging was measured before and during an auditory stimulus, then with midazolam sedation, and then during a second auditory stimulus with continuous midazolam sedation. After 4 h, explicit and implicit memories were assessed. There was no evidence of explicit memory at the two levels of midazolam sedation. Implicit memory was retained at a mild level of midazolam sedation but absent at a deep level of midazolam sedation. At a mild level of midazolam sedation, activation of all brain areas by auditory stimulus (as measured by functional magnetic resonance imaging) was uninhibited. However, a deep level of midazolam sedation depressed activation of the superior temporal gyrus by auditory stimulus. We conclude that midazolam does not abolish implicit memory at a mild sedation level, but can abolish both explicit and implicit memories at a deep sedation level. The superior temporal gyrus may be one of the target areas.
Integrating geo‐referenced multiscale and multidisciplinary data for the management of biodiversity in livestock genetic resources
Authors: Joost S. , Colli L. , Baret P. V. , Garcia J. F. , Boettcher P. J. , Tixier‐Boichard M. , Ajmone‐Marsan P. ,   The GLOBALDIV Consortium
Published: April 2010

In livestock genetic resource conservation, decision making about conservation priorities is based on the simultaneous analysis of several different criteria that may contribute to long‐term sustainable breeding conditions, such as genetic and demographic characteristics, environmental conditions, and role of the breed in the local or regional economy. Here we address methods to integrate different data sets and highlight problems related to interdisciplinary comparisons. Data integration is based on the use of geographic coordinates and Geographic Information Systems (GIS). In addition to technical problems related to projection systems, GIS have to face the challenging issue of the non homogeneous scale of their data sets. We give examples of the successful use of GIS for data integration and examine the risk of obtaining biased results when integrating datasets that have been captured at different scales.
Genetic diversity in farm animals – a review
Authors: Groeneveld L. F. , Lenstra J. A. , Eding H. , Toro M. A. , Scherf B. , Pilling D. , Negrini R. , Finlay E. K. , Jianlin H. , Groeneveld E. , Weigend S. ,   The GLOBALDIV Consortium
Published: April 2010

Domestication of livestock species and a long history of migrations, selection and adaptation have created an enormous variety of breeds. Conservation of these genetic resources relies on demographic characterization, recording of production environments and effective data management. In addition, molecular genetic studies allow a comparison of genetic diversity within and across breeds and a reconstruction of the history of breeds and ancestral populations. This has been summarized for cattle, yak, water buffalo, sheep, goats, camelids, pigs, horses, and chickens. Further progress is expected to benefit from advances in molecular technology.
Clinical predictors of severe malarial anaemia in a holoendemic Plasmodium falciparum transmission area
Authors: Novelli Enrico M. , Hittner James B. , Davenport Gregory C. , Ouma Collins , Were Tom , Obaro Stephen , Kaplan Sandra , Ong’echa John M. , Perkins Douglas J.
Published: April 2010

Severe malarial anaemia (SMA) is a common complication of Plasmodium falciparum infections, resulting in mortality rates that may exceed 30% in paediatric populations residing in holoendemic transmission areas. One strategy for reducing the morbidity and mortality associated with SMA is to identify clinical predictors that can be readily recognized by caregivers for prompt therapeutic interventions. To determine clinical predictors of SMA, Kenyan children (3–36 months, n = 671) presenting with acute illness at a rural hospital in Siaya District were recruited. Demographic, clinical, laboratory and haematological parameters were measured upon enrolment. As human immunodeficiency virus‐1 and bacteraemia promote reduced haemoglobin (Hb) concentrations, children with these infections were excluded from the analyses. Children with P. falciparum mono‐infections (n = 355) were stratified into three groups: uncomplicated malaria (Hb ≥ 110 g/l); non‐SMA (60 ≤ Hb < 109), and SMA (Hb < 60 g/l). SMA was characterized by a younger age, monocytosis, thrombocytopenia, reticulocytosis, reduced erythropoiesis, elevated pigment‐containing monocytes (PCM), respiratory distress, conjunctival and palmar pallor, splenomegaly, signs of malnutrition, and protracted fever and emesis. Logistic regression analysis demonstrated that age, reticulocyte count, presence of PCM and conjunctival and palmar pallor were significant predictors of SMA. Recognition of these clinical signs in children residing in resource‐poor settings may help to guide the identification and management of SMA.
Diagnosis of post‐transplant lymphoproliferative disorder in solid organ transplant recipients – BCSH and BTS Guidelines
Authors: Parker Anne , Bowles Kristin , Bradley J. Andrew , Emery Vincent , Featherstone Carrie , Gupte Girish , Marcus Robert , Parameshwar Jayan , Ramsay Alan , Newstead Charles ,   (British Transplantation Society Lead) Writing group: On behalf of the Haemato‐oncology Task Force of the British Committee for Standards in Haematology and British Transplantation Society
Published: April 2010

A joint working group established by the Haemato‐oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Transplantation Society (BTS) has reviewed the available literature and made recommendations for the diagnosis and management of post‐transplant lymphoproliferative disorder (PTLD) in adult recipients of solid organ transplants. This review details the risk factors predisposing to development, initial features and diagnosis. It is important that the risk of developing PTLD is considered when using post transplant immunosuppression and that the appropriate investigations are carried out when there are suspicions of the diagnosis. These must include tissue for histology and computed tomography scan to assess the extent of disease. These recommendations have been made primarily for adult patients, there have been some comments made with regard to paediatric practice.
Pharmacokinetics and pharmacokinetic/pharmacodynamic associations of ofatumumab, a human monoclonal CD20 antibody, in patients with relapsed or refractory chronic lymphocytic leukaemia: a phase 1–2 study
Authors: Coiffier Bertrand , Losic Nedjad , Rønn Birgitte Biilmann , Lepretre Stéphane , Pedersen Lars Møller , Gadeberg Ole , Frederiksen Henrik , Van Oers Marinus H. J. , Wooldridge James , Kloczko Janusz , Holowiecki Jerzy , Hellmann Andrzej , Walewski Jan , Robak Tadeusz , Petersen Jørgen
Published: April 2010

The purpose of this phase 1–2 study was to investigate the association between the pharmacokinetic properties of ofatumumab, a human monoclonal CD20 antibody, and outcomes in 33 patients with relapsed/refractory chronic lymphocytic leukaemia receiving 4 weekly infusions of ofatumumab. The ofatumumab concentration profiles were fitted well by a two‐compartment model with different elimination rate constant at first infusion compared to the remaining infusions in line with the observed rapid and sustained B‐cell depletion. Exposure to ofatumumab was linked to clinical outcomes: high exposure was associated with higher probability of overall clinical response and longer progression‐free survival. This association still remained statistically significant even when adjusting for relevant baseline covariates including tumour burden. The trial was registered at http://www.clinicaltrials.gov (NCT00093314).
NT‐proBNP as a marker of cardiopulmonary status in sickle cell anaemia in Africa
Authors: Aliyu Zakari Y. , Suleiman Aisha , Attah Ester , Mamman Aisha I. , Babadoko Aliyu , Nouraie Mehdi , Mendelsohn Laurel , Kato Gregory J. , Gordeuk Victor R. , Gladwin Mark T.
Published: April 2010

N‐terminal (NT) pro‐brain natriuretic peptide (proBNP) ≥160 ng/l has a 78% positive predictive value for pulmonary hypertension and is associated with increased mortality in US sickle cell disease patients, but the importance in sickle cell disease patients in Africa is not known. In a cross‐sectional study at Ahmadu Bello University Teaching Hospital, Shika‐Zaria, Nigeria, we studied 133 hydroxycarbamide‐naïve Nigerian sickle cell anaemia patients aged 18–52 years at steady‐state and 65 healthy controls. Twenty‐six percent of patients versus 5% of controls had NT‐proBNP ≥160 ng/l (P = 0·0006). By logistic regression among the patients, human immunodeficiency virus seropositivity, higher serum ferritin and lower haemoglobin or higher lactate dehydrogenase independently predicted elevated NT‐proBNP. After adjustment for haemoglobin concentration, elevated NT‐proBNP concentration was associated with an estimated 7·8‐fold increase in the odds of severe functional impairment, defined as an inability to walk more than 300 m in 6 min (95% confidence interval 1·5–32·6; P = 0·005). Similarly, elevated tricuspid regurgitation velocity was associated with an estimated 5·6‐fold increase in the odds of functional impairment (95% confidence interval 1·5–21·0; P = 0·011). In conclusion, NT‐proBNP elevation is common and is associated with markers of anaemia, inflammation and iron status and with severe functional impairment among sickle cell anaemia patients in Nigeria.
A meta‐synthesis describing the relationships between patients, informal caregivers and health professionals in home‐care settings
Authors: Lindahl Berit , Lidén Eva , Lindblad Britt‐Marie
Published: April 2010

Aim. The present study describes, through a meta‐synthesis, the relationship between patients, informal caregivers and health professionals involved in home care.

Background. Today, many people receive help from health care professionals in their homes with the consequence that, for many health care professionals, their working place is the patients’ homes. Research that addresses the dynamics in the caring relationship in home care seems to be rare.

Design. A meta‐synthesis is an integrated interpretation of qualitative research findings, which is more substantive than the results from each individual investigation.

Method. We performed a systematic literature search regarding studies published during the period 1992–2005, using the search terms home nursing, professional and home health care. The included studies described relations in a home care context, between health professionals and patients or relations between health professionals, patients and their informal caregivers published in the same study.

Results. The findings showed that when professionals entered people’s home, the private area changed. The study presents an interpretation of the changed meanings of home as the place and space for professional care. We described the meanings of the relationship in two main themes with subthemes. The main themes are ‘being there’ and ‘home care as a co‐creation’. The understanding of relationships in home care is seen as the development of a professional friendship. This concept is reflected on through the writings of Aristotle and Alberoni.

Conclusion. To address these concerns, it is important that home care providers, recipients and their family members develop friendships. These friendships should be a part of any professional relationship.

Relevance to clinical practice. When health professionals enter patients’ homes, they have to be aware of the risk of transgressing borders of privacy. In addition, devaluing patients’ or their informal caregivers’ knowledge and their opinions about the care is interpreted as an exercise of institutional power.
On the relationship between motor performance and executive functioning in children with intellectual disabilities
Authors: Hartman E. , Houwen S. , Scherder E. , Visscher C.
Published: April 2010

Background  It has been suggested that children with intellectual disabilities (ID) have motor problems and higher‐order cognitive deficits. The aim of this study was to examine the motor skills and executive functions in school‐age children with borderline and mild ID. The second aim was to investigate the relationship between the two performance domains.

Methods  Sixty‐one children aged between 7 and 12 years diagnosed with borderline ID (33 boys and 28 girls; 71 < IQ < 79) and 36 age peers with mild ID (24 boys and 12 girls; 54 < IQ < 70) were assessed. Their abilities were compared with those of 97 age‐ and gender‐matched typically developing children. Qualitative motor skills, i.e. locomotor ability and object control, were evaluated with the Test of Gross Motor Development (TGMD‐2). Executive functioning (EF), in terms of planning ability, strategic decision‐making and problem solving, was gauged with the Tower of London (TOL) task.

Results  Compared with the reference group, the full ID cohort scored significantly lower on all assessments. For the locomotor skills, the children with mild ID scored significantly lower than the children with borderline ID, but for the object control skills and the TOL score, no significant differences between the two groups were found. Motor performance and EF correlated positively. At the most complex level, the TOL showed decision time to be a mediator between motor performance and EF: the children with the lower motor scores had significantly shorter decision times and lower EF scores. Analogously, the children with the lower object control scores had longer execution times and lower EF scores.

Conclusions  The current results support the notion that besides being impaired in qualitative motor skills intellectually challenged children are also impaired in higher‐order executive functions. The deficits in the two domains are interrelated, so early interventions boosting their motor and cognitive development are recommended.
The specificity of allelopathy in rice (Oryza sativa)
Authors: SEAL A N , PRATLEY J E
Published: April 2010

Seal AN & Pratley JE (2010). The specificity of allelopathy in rice (Oryza sativa). Weed Research50, 303–311.

The objective of the current research was to evaluate the capability of individual rice cultivars to have multi‐weed suppressive effects against five currently and potentially important Australian aquatic rice weeds. These weed species are problematic, as resistance occurs to the major herbicide available for their control. Twenty‐seven rice cultivars were screened in the laboratory for their allelopathic impact using the Equal Compartment Agar Method against the weeds. Significant differences existed between rice cultivars in their ability to suppress the root growth of each weed studied. Correlations of root inhibition values between combinations of the tested weeds were undertaken to establish rice cultivar inhibition against multiple weed species. All correlations were significant. The highest correlation occurred with Alisma lanceolatum and Sagittaria graminea (r = 0.93), closely related species, and the lowest (r = 0.58) was obtained when comparing Echinochloa crus‐galli with S. montevidensis, being unrelated species. The seven most allelopathic cultivars overall inhibited mean weed growth by more than 90%, demonstrating that particular rice cultivars can significantly inhibit multiple weed species. Cluster analysis of the available pedigree information for the tested rice cultivars showed that several rice cultivars with high allelopathic impact in bioassay were grouped in two clusters. This information is useful for plant breeders aiming to incorporate weed allelopathic capability into new crop cultivars.
Non‐invasive ICG‐clearance: a useful tool for the management of hepatic artery thrombosis following liver transplantation
Authors: Levesque E. , Hoti E. , Azoulay D. , Adam R. , Samuel D. , Castaing D. , Saliba F.
Published: April 2010

Levesque E, Hoti E, Azoulay D, Adam R, Samuel D, Castaing D, Saliba F. Non‐invasive ICG‐clearance: a useful tool for the management of hepatic artery thrombosis following liver transplantation.  Clin Transplant 2011: 25: 297–301. © 2010 John Wiley & Sons A/S.

Abstract:  Background:  The clinical presentation of hepatic artery thrombosis (HAT) post‐liver transplantation (LT) varies considerably. Doppler ultrasonography (Doppler US) is the first line investigation, with a diagnostic sensitivity for HAT as high as 92%. Because indocyanine green (ICG) elimination from the blood depends among other factors on the hepatic blood flow, we hypothesized that plasma disappearance rate of indocyanine green (PDR‐ICG) can be influenced by the flow in the hepatic artery. Thus, we evaluated the role of PDR‐ICG measurement in HAT diagnosis in post‐LT patients.

Patients and methods:  Fourteen liver transplant patients with no visible flow in the hepatic artery (Doppler US) were identified. Of the 14, seven patients had HAT confirmed by CT‐angiography. The PDR‐ICG measurement, an investigation routinely used in our center, was performed in all 14 patients.

Results:  The PDR‐ICG in patients with HAT was significantly lower than in patients without HAT (5.8 ± 4.3 vs. 23.8 ± 7.4%/min, p = 0.0009). In patients with HAT, after the revascularization, the PDR‐ICG value increased (5.8 ± 4.3 vs. 15.6 ± 3.5%/min, p = 0.006).

Conclusion:  The ICG elimination may be an adjunct diagnostic tool in the management of patients with suspected HAT following LT.
Neuroprotective effect of asymmetric dimethylarginine against 1‐methyl‐4‐phenylpyridinium ion‐induced damage in PC12 cells
Authors: Tang Xiao‐Qing , Li Yu‐Juan , Zhao Jing , Shen Xing‐Tian , Yang Chun‐Tao , Fan Li‐Li , Hu Bi , Li Yuan‐Jian , Liao Duan‐Fan
Published: April 2010

1. Asymmetric dimethylarginine (ADMA) is a well‐known endogenous nitric oxide synthase (NOS) inhibitor. Although it has been shown to be a novel risk marker in cardiovascular medicine and chronic kidney disease, we speculated that in some states associated with excess of nitric oxide (NO), such as 1‐methyl‐4‐phenylpyridinium ion (MPP+)‐induced neuronal injury, ADMA might be protective by limiting the toxic effect of high concentrations of NO.

2. The aim of the present study is to explore the protection of ADMA against MPP+‐induced apoptosis and the molecular mechanisms underlying in PC12 cells.

3. We found that exogenous application of ADMA obviously protected PC12 cells against MPP+‐induced cytotoxicity and apoptosis not only by reducing the loss of mitochondrial membrane potential, but also by attenuating an increase in intracellular reactive oxygen species. Moreover, ADMA attenuated MPP+‐induced excessive activation of nitric oxide synthase and overproduction of NO.

4. The results of the present study suggest that the protection caused by ADMA is related to preserving mitochondrial membrane potential and attenuating the MPP+‐induced intracellular reactive oxygen species generation through inhibiting nitric oxide synthase activity and limiting NO generation.
RNA interference‐mediated silencing of UBCH10 gene inhibits colorectal cancer cell growth in vitro and in vivo
Authors: Chen Shi‐Min , Jiang Chun‐Ying , Wu Jian‐Ying , Liu Bin , Chen Ying‐Jian , Hu Cheng‐Jin , Liu Xian‐Xi
Published: April 2010

1. UbcH10 is the cancer‐related E2 ubiquitin‐conjugating enzyme, and its overexpression has been demonstrated in a variety of malignancies. The aim of the present study is to silence UbcH10 gene by RNA interference (RNAi) and to observe its inhibitory effect on the colorectal cancer cell growth in vitro and in vivo.

2. We constructed the expression vector pGPU6/GFP/Neo/UbcH10‐RNAi (pUbcH10‐RNAi), which contained a UbcH10 short hairpin RNA expression cassette. Then the UbcH10 gene silencing cell lines LoVo/UbcH10‐RNAi and HT‐29/UbcH10‐RNAi were established. Reverse transcription‐polymerase chain reaction and western blot analysis were used to evaluate the expression of the UbcH10 gene. Cell Counting Kit‐8 was used to assess properties of tumour cell growth in vitro. Flow cytometry was used to detect the effect of pUbcH10‐RNAi on the cell cycle of colorectal cancer cells. Furthermore, the anti‐tumour effects of pUbcH10‐RNAi were evaluated in vivo in a nude mouse xenografts model.

3. Results demonstrated that UbcH10 gene expression was significantly decreased in pUbcH10‐RNAi treated cells. Colorectal cancer cells growth was markedly suppressed in the pUbcH10‐RNAi group compared with control conditions and colorectal cancer cells were arrested in the G2‐M phase. In vivo, the downregulation of UbcH10 gene expression by pUbcH10‐RNAi also inhibited tumour growth in a nude mice xenograft model.

4. Our study suggests that RNA interference‐mediated silencing of UbcH10 gene has anti‐tumour activity on colorectal cancer and might have therapeutic potential for the treatment of colorectal cancer.
Episodic vomiting and headache in children: consider occipital epilepsy
Authors: Lope Raja Juanita Raja , Wong Sau Wei , Wu Loo Ling
Published: April 2010

Children with occipital seizures often have ictal autonomic symptoms such as pallor and vomiting and lack motor manifestations. This has lead to misdiagnosis of occipital seizures in children. The following case report highlights the clinical features of a child with occipital epilepsy misdiagnosed as having migraine. The aetiology of symptomatic occipital epilepsy will be discussed.
Hypokalaemia and failure to thrive: report of a misleading onset
Authors: Conti Giovanni , Vitale Agata , Tedeschi Silvana , Syrén Marie‐Louise , Pantano Roberta , Chimenz Roberto , Fede Salvatore , La Torre Francesco , Coviello Domenico , Fede Carmelo
Published: April 2010

Aim:  We report a case of Gitelman Syndrome (GS) in a 9‐year‐old girl, previously diagnosed as a Bartter syndrome at one year of life.

Methods:  She had been treated with potassium, for over 8 years and was admitted because of fatigue, numbness and weakness of both legs. The patient has typical laboratory findings, including hypokalemia, metabolic alkalosis, hypomagnesemia, and hypocalciuria, thus GS was suspected.

Results:  Genetic analysis was performed two mutations IVS9(+1)G>T were detected in the thiazide‐sensitive Na‐Cl cotransporter (TSC) gene (SLC12A3), thus she was diagnosed as having GS. She was treated with oral potassium and magnesium supplements with resolution of the symptoms.

Conclusion:  This case reminded us that doctors should be alert to the initial presentation of renal tubular diseases. Detailed electrolyte analysis, hormone evaluations and clinic follow‐up are mandatory for their correct differential diagnosis.