bluuebunny/crossref_metadata_2025_split huggingface dataset:
Barrett's esophagus is characterized by the absence of Helicobacter pylori infection and high levels of serum pepsinogen I concentration in Japan
Authors: Abe Yasuhiko , Iijima Katsunori , Koike Tomoyuki , Asanuma Kiyotaka , Imatani Akira , Ohara Shuichi , Shimosegawa Tooru 
Published: January 2009

AbstractBackground and Aim:  It has been reported that patients with Barrett's esophagus (BE) may have gastric acid hypersecretion. Serological markers such as serum pepsinogen or gastrin have been used to estimate the gastric secretory function. The aim of this study was to compare the serum pepsinogen and gastrin concentrations in view of Helicobacter pylori infection status between BE patients and the controls.Methods:  Thirty‐six patients with long‐segment BE were enrolled in this study. Three age‐ and sex‐matched controls were assigned to each patient. Serum pepsinogen and gastrin concentrations were measured by radioimmunoassay and H. pylori infection was determined by histology and serum IgG antibodies.Results:  Helicobacter pylori infection was present in 4 of 36 patients (11%) with BE and in 80 of 108 controls (74%), being less prevalent in BE patients than in the controls (P < 0.0001). When examined in the H. pylori‐negative subjects, both the serum pepsinogen I and pepsinogen II concentrations in BE patients were significantly higher than those in the controls (mean pepsinogen I:BE 51.0 ± 14.0 ng/mL vs control 38.9 ± 13.5 ng/mL, P = 0.0012; mean pepsinogen II:BE 10.8 ± 4.0 ng/mL vs control 7.9 ± 2.0 ng/mL, P = 0.0097). There was no significant difference in the serum gastrin levels between BE patients and the controls irrespective of the H. pylori infection status.Conclusions:  Most of the Japanese BE patients are characterized by the absence of H. pylori infection and high levels of serum pepsinogen. Determination of the serum pepsinogen level in combination with the H. pylori infection status could be a useful serological marker for BE screening.
Histopathological features and accuracy for diagnosing biliary atresia by prelaparotomy liver biopsy in developing countries
Authors: Rastogi Archana , Krishnani Narendra , Yachha Surender Kumar , Khanna Vikrant , Poddar Ujjal , Lal Richa 
Published: January 2009

AbstractBackground and Aim:  A major challenge in neonatal cholestasis (NC) is to differentiate biliary atresia (BA) from other non‐atretic causes. In developing countries there are considerable problems of late referral of NC cases and performing surgery without prelaparotomy liver biopsy that contributes to a high proportion of negative laparotomy and increased morbidity. We evaluated the hepatic histopathology for presence of features that correlate best with the diagnosis of BA and assessed the accuracy of percutaneous liver biopsy.Methods:  Fifty‐five cases of NC that fulfilled the selection criteria and had liver biopsy available were analyzed. Among the 49 adequate liver biopsies, 28 cases were diagnosed as BA, 15 neonatal hepatitis (NH) and 6 were due to other causes. Validity of percutaneous liver biopsy diagnoses was compared with confirmed cases by laparotomy findings and 1‐year follow up. Twelve histological parameters of confirmed cases of BA and NH were evaluated by logistic regression analyses.Results:  Ductular proliferation (P = 0.0002), bile duct and ductular bile plugs (P = 0.009), and portal fibrosis (P = 0.002) were the best indicators of BA and among them ductular proliferation was the most important in distinguishing BA from NH. Ductal plate malformation was observed in 17.9% cases of BA. Sensitivity and specificity of percutaneous liver biopsy for diagnosing BA was 88.2% each.Conclusion:  Percutaneous liver biopsy is highly accurate (88.2%) in diagnosing BA. In developing countries. This investigation should be done to decrease the frequency of negative laparotomy and to achieve cost–benefit with reduced morbidity.
Adverse medical events associated with cataract surgery performed under topical anaesthesia
Authors: Sharwood Phillipa L , Thomas David , Roberts Timothy V 
Published: January 2009

AbstractBackground:  Cataract surgery in Australia is increasingly performed in an elderly population with multiple medical comorbidities. The purpose of this study was to investigate the frequency and type of adverse medical events associated with cataract surgery performed under topical anaesthesia with light sedation.Methods:  Retrospective analysis was undertaken for 631 consecutive cases of clear corneal phaco‐emulsification and implant surgery performed under assisted topical anaesthesia, by a single surgeon (TR) in a private ophthalmic day surgery unit. In the 238 patients who underwent bilateral surgery, data from the first procedure for each patient were analysed, unless the second procedure was associated with greater morbidity.Results:  A total of 393 procedures were included in the study. The mean age was 73 ± 11 years with 75% of patients having at least one significant medical comorbidity. The most common comorbidities were hypertension (51%), gastro‐oesophageal reflux (19%), angina and myocardial infarction (14%), diabetes (13%) and asthma (9%). Significant intraoperative adverse medical events requiring intervention occurred in four cases (1%): bradycardia occurred in three cases and hypotension in one case. None of these adverse events resulted in death or hospitalization. There were no postoperative adverse events, hospitalizations or deaths within 7 days. Minor changes in heart rate, blood pressure and oximetry not requiring intervention were observed in 35 cases (9%).Conclusion:  This retrospective analysis shows that cataract surgery performed under assisted topical anaesthesia is safe with a low rate of systemic complications despite being performed in an elderly population.
Determinants of assemblage structure in Neotropical dry forest lizards
Authors: De PINHO WERNECK FERNANDA , COLLI GUARINO RINALDI , VITT LAURIE JOSEPH 
Published: January 2009

AbstractWe investigated the structure of a lizard assemblage from Seasonally Dry Tropical Forest enclaves in the Brazilian Cerrado biome, by testing the roles of ecological and historical components. We analysed data from 469 individuals, belonging to 18 lizard species, sampled by a combination of pitfall, funnel and glue traps, as well as by haphazard sampling. Null model analyses and Canonical Phylogenetic Ordination analysis, coupled with Monte Carlo simulations, revealed lack of both ecological and phylogenetic structure in microhabitat use. Conversely, these analyses revealed a mean overlap in diet composition significantly smaller than expected by chance and significant historical structure. Structure in diet composition was due to phylogenetic effects corresponding to the most basal divergence of the squamate phylogeny (Iguania/Scleroglossa) and the clades Teiidae and Gymnophthalmidae. Among lizards, evolutionary constraints on microhabitat use appear less than on prey use, suggesting that the availability of historically preferred prey types moderates microhabitat selection. The lack of structure in microhabitat use suggests absence of competitive interactions on the spatial component. On the other hand, food preferences have a deep historical basis and do not reflect current competitive interactions.
Bilateral motor unit synchronization of leg muscles during a simple dynamic balance task
Authors: Boonstra Tjeerd W. , Daffertshofer Andreas , Roerdink Melvyn , Flipse Ivo , Groenewoud Karin , Beek Peter J. 
Published: January 2009

AbstractTo handle the rich repertoire of behavioural goals, the CNS has to control the many degrees of freedom of the musculoskeletal system in a flexible manner. This problem can be drastically simplified if muscle synergies serve as the to‐be‐controlled building blocks of motor performance, instead of the individual degrees of freedom. Muscle synergies have been identified as coherent activation patterns of a group of muscles in space or time, but the neural mechanisms underlying their formation remain largely unknown. Here we evaluated the hypothesis that synergies are reflected in common input to different contributing muscles, and investigated modulations in motor unit (MU) synchronization of homologous muscles during a rhythmic balance task. If common input is related to muscle synergies, the resultant MU synchronization should not be static but task dependent and, in the present context, vary in time. Coherence between surface electromyographic signals of bilateral leg muscles revealed MU synchronization in two distinct frequency bands. MU synchronization was not constant but modulated within a movement cycle, and its time course resembled the activation patterns of the muscles. These results are congruent with a linkage between MU synchronization and muscle synergies, and suggest that MU synchronization provides an expedient method for studying synergy‐related neural mechanisms.
Tectonigral projections in the primate: a pathway for pre‐attentive sensory input to midbrain dopaminergic neurons
Authors: May Paul J. , McHaffie John G. , Stanford Terrence R. , Jiang Huai , Costello M. Gabriela , Coizet Veronique , Hayes Lauren M. , Haber Suzanne N. , Redgrave Peter 
Published: January 2009

AbstractMuch of the evidence linking the short‐latency phasic signaling of midbrain dopaminergic neurons with reward‐prediction errors used in learning and habit formation comes from recording the visual responses of monkey dopaminergic neurons. However, the information encoded by dopaminergic neuron activity is constrained by the qualities of the afferent visual signals made available to these cells. Recent evidence from rats and cats indicates the primary source of this visual input originates subcortically, via a direct tectonigral projection. The present anatomical study sought to establish whether a direct tectonigral projection is a significant feature of the primate brain. Injections of anterograde tracers into the superior colliculus of macaque monkeys labelled terminal arbors throughout the substantia nigra, with the densest terminations in the dorsal tier. Labelled boutons were found in close association (possibly indicative of synaptic contact) with ventral midbrain neurons staining positively for the dopaminergic marker tyrosine hydroxylase. Injections of retrograde tracer confined to the macaque substantia nigra retrogradely labelled small‐ to medium‐sized neurons in the intermediate and deep layers of the superior colliculus. Together, these data indicate that a direct tectonigral projection is also a feature of the monkey brain, and therefore likely to have been conserved throughout mammalian evolution. Insofar as the superior colliculus is configured to detect unpredicted, biologically salient, sensory events, it may be safer to regard the phasic responses of midbrain dopaminergic neurons as ‘sensory prediction errors’ rather than ‘reward prediction errors’, in which case dopamine‐based theories of reinforcement learning will require revision.
Transplantation of human embryonic stem cell‐derived neural precursor cells and enriched environment after cortical stroke in rats: cell survival and functional recovery
Authors: Hicks Anna U. , Lappalainen Riikka S. , Narkilahti Susanna , Suuronen Riitta , Corbett Dale , Sivenius Juhani , Hovatta Outi , Jolkkonen Jukka 
Published: January 2009

AbstractCortical stem cell transplantation may help replace lost brain cells after stroke and improve the functional outcome. In this study, we transplanted human embryonic stem cell (hESC)‐derived neural precursor cells (hNPCs) or vehicle into the cortex of rats after permanent distal middle cerebral artery occlusion (dMCAO) or sham‐operation, and followed functional recovery in the cylinder and staircase tests. The hNPCs were examined prior to transplantation, and they expressed neuroectodermal markers but not markers for undifferentiated hESCs or non‐neural cells. The rats were housed in either enriched environment or standard cages to examine the effects of additive rehabilitative therapy. In the behavioral tests dMCAO groups showed significant impairments compared with sham group before transplantation. Vehicle groups remained significantly impaired in the cylinder test 1 and 2 months after vehicle injection, whereas hNPC transplanted groups did not differ from the sham group. Rehabilitation or hNPC transplantation had no effect on reaching ability measured in the staircase test, and no differences were found in the cortical infarct volumes. After 2 months we measured cell survival and differentiation in vivo using stereology and confocal microscopy. Housing had no effect on cell survival or differentiation. The majority of the transplanted hNPCs were positive for the neural precursor marker nestin. A portion of transplanted cells expressed neuronal markers 2 months after transplantation, whereas only a few cells co‐localized with astroglial or oligodendrocyte markers. In conclusion, hESC‐derived neural precursor transplants provided some improvement in sensorimotor function after dMCAO, but did not restore more complicated sensorimotor functions.
Genes, gene flow and adaptation ofDiabrotica virgifera virgifera
Authors: Miller Nicholas J. , Guillemaud Thomas , Giordano Rosanna , Siegfried Blair D. , Gray Michael E. , Meinke Lance J. , Sappington Thomas W. 
Published: January 2009

Abstract1 Diabrotica virgifera virgiferahas emerged as a major pest of cultivated maize, due to a combination of its high capacity to inflict economic damage, adaptability to pest management techniques and invasiveness.2 This review presents a survey of the current state of knowledge about the genetics ofD. v. virgifera. In addition, the tools and resources currently available toDiabroticageneticists are identified, as are areas where knowledge is lacking and research should be prioritized.3 A substantial amount of information has been published concerning the molecular phylogenetic relationships ofD. v. virgiferato other chrysomelids.4 There is a growing literature focused on the population genetics and evolution of the species. Several adaptations to anthropogenic selection pressure have been studied, with resistance to synthetic insecticides providing some particularly well‐characterized examples.5 A notable deficiency is a lack of studies directed toward the formal genetics ofD. v. virgifera.
International cooperation on western corn rootworm ecology research: state‐of‐the‐art and future research
Authors: Moeser J. , Guillemaud T. 
Published: January 2009

Abstract1 Invasive pest species are challenging partly because the invasion process may be highly dynamic and because of the lack of knowledge of many researchers, professionals and farmers in the newly‐invaded regions. The chrysomelid Diabrotica virgifera virgifera LeConte is such an invasive pest. It has been the main pest of continuous maize in the U.S.A. for more than 60 years and is currently spreading throughout Europe.2 In the area with a long history of this pest (Central and North America), scientific knowledge concerning the ecology of this pest has accumulated over the last decades. This resource is of great importance to both America and Europe and has to be gathered, shared and adapted to new situations. We therefore examined, both qualitatively and quantitatively, the scientific literature relating to D. virgifera virgifera ecology.3 The quantitative analysis suggests that research on D. virgifera virgifera ecology is still in its infancy in Europe and suffers from geographical barriers (between Europe and North America and between linguistic areas within Europe) and that scientific communication should be strengthened both between North America and Europe and within Europe.4 As a first solution to this problem, we introduce three companion review articles that constitute a landmark for D. virgifera virgifera research, enabling European and American scientists and decision‐makers to orient themselves and discover new opportunities for research. We also stress that international research cooperation is the most important key to successfully manage invasive species.
Dynamics and functional relevance of ammonia‐oxidizing archaea in two agricultural soils
Authors: Schauss Kristina , Focks Andreas , Leininger Sven , Kotzerke Anja , Heuer Holger , Thiele‐Bruhn Sören , Sharma Shilpi , Wilke Berndt‐Michael , Matthies Michael , Smalla Kornelia , Munch Jean Charles , Amelung Wulf , Kaupenjohann Martin , Schloter Michael , Schleper Christa 
Published: January 2009

SummaryCrucial steps in geochemical cycles are in many cases performed by more than one group of microorganisms, but the significance of this functional redundancy with respect to ecosystem functioning is poorly understood. Ammonia‐oxidizing archaea (AOA) and their bacterial counterparts (AOB) are a perfect system to address this question: although performing the same transformation step, they belong to well‐separated phylogenetic groups. Using pig manure amended with different concentrations of sulfadiazine (SDZ), an antibiotic that is frequently used in veterinary medicine, it was possible to affect AOB and AOA to different degrees. Addition of manure stimulated growth of AOB in both soils and, interestingly, also growth of AOA was considerably stimulated in one of the soils. The antibiotic treatments decreased the manure effect notably on AOB, whereas AOA were affected to a lower extent. Model calculations concerning the respective proportions of AOA and AOB in ammonia oxidation indicate a substantial contribution of AOA in one of the soils that further increased under the influence of SDZ, hence indicating functional redundancy between AOA and AOB.
Viral biogeography revealed by signatures in Sulfolobus islandicus genomes
Authors: Held Nicole L. , Whitaker Rachel J. 
Published: January 2009

SummaryViruses are a driving force of microbial evolution. Despite their importance, the evolutionary dynamics that shape diversity in viral populations are not well understood. One of the primary factors that define viral population structure is coevolution with microbial hosts. Experimental models predict that the trajectory of coevolution will be determined by the relative migration rates of viruses and their hosts; however, there are no natural microbial systems in which both have been examined. The biogeographic distribution of viruses that infect Sulfolobus islandicus is investigated using genome comparisons among four newly identified, integrated, Sulfolobus spindle‐shaped viruses and previously sequenced viral strains. Core gene sequences show a biogeographic distribution where viral genomes are specifically associated with each local population. In addition, signatures of host–virus interactions recorded in the sequence‐specific CRISPR (clustered regularly interspaced short palindromic repeats) system show that hosts have interacted with viral communities that are more closely related to local viral strains than to foreign ones. Together, both proviral and CRISPR sequences show a clear biogeographic structure for Sulfolobus viral populations. Our findings demonstrate that virus–microbe coevolution must be examined in a spatially explicit framework. The combination of host and virus biogeography suggests a model for viral diversification driven by host immunity and local adaptation.
Development of a bacterial challenge test for gnotobiotic sea bass (Dicentrarchus labrax) larvae
Authors: Dierckens K. , Rekecki A. , Laureau S. , Sorgeloos P. , Boon N. , Van den Broeck W. , Bossier P. 
Published: January 2009

SummaryThe use of probiotic microorganisms in aquaculture is gaining a lot of interest. Gnotobiotic model systems are required in order to fully understand the effects and modes‐of‐action of these microorganisms, as the native microbial communities present in non‐sterile animals can lead to false conclusions. In this study, a gnotobiotic sea bass larvae (Dicentrarchus labrax) test system was developed. In order to obtain bacteria‐free animals, the eggs were disinfected with glutaraldehyde and subsequently incubated in a solution of rifampicin and ampicillin. Axenity was confirmed using culture‐dependent and ‐independent techniques. The gnotobiotic larvae were fed axenic Artemia sp. from 7 days after hatching onwards. In the challenge test, one of the three opportunistic pathogens, Aeromonas hydrophila, Listonella anguillarum serovar O1 and O2a, was added to the model system via the water and encapsulated in Artemia sp. Only serovar O2a led to increased mortality in the sea bass larvae. The presented gnotobiotic model can be used for research on, among others, reciprocal metabolic effects between microorganisms and the host (e.g. as measured by gene expression), immunostimulants, pharmacological research and the histological development of the gastrointestinal tract and growth of larvae.
Sequestered organelles sustain aerobic microbial life in anoxic environments
Authors: Esteban Genoveva F. , Finlay Bland J. , Clarke Ken J. 
Published: January 2009

SummaryWe report aerobic eukaryotic microbial life in the dimly lit anoxic water layer of a small freshwater lake. The microbial eukaryote is the ciliated protozoonHistiobalantium natans. Electron microscopy of thin sections shows that the cytoplasm of the ciliate harbours sequestered chloroplasts and sequestered mitochondria. The sequestered chloroplasts are attached or in very close proximity to the ciliate's own mitochondria. The sequestered mitochondria also seem to be associated with host‐ciliate mitochondria. We suggest that the oxygenic photosynthetic activity of sequestered chloroplasts, perhaps enhanced by respiration in sequestered mitochondria, contributes to servicing the respiratory oxygen requirements of the ciliate host in its anoxic habitat. Our observations are novel, with the discovery of an aerobic microbial eukaryote capable of thriving and completing its life cycle in an anoxic environment, fuelled by oxygen generated by sequestered chloroplasts. The acknowledged flexibility and functional diversity within eukaryotic microbial communities still have many secrets to release.
Draping and associated equipment for indwelling catheter manipulation by hospital staff: an assessment of attitudes and adequacy
Authors: Weerakoon Mahesha , Lawrentschuk Nathan 
Published: January 2009

OBJECTIVETo address the usability and safety aspects of current equipment for indwelling urinary catheter (IDC) manipulation, by assessing the attitudes of doctors and nurses to infection control, occupational health and environmental waste, and the perceived adequacy of available catheter packs, particularly drapes, when performing such manipulations.SUBJECTS AND METHODSA self‐administered survey instrument was created using an online database and completed by doctors and nurses. The survey covered basic demographics and experience with IDC, attitudes to infection control, occupational health and safety, and the environment, as well as adequacy of current equipment in containing spillage of urine and/or blood.RESULTSIn all, 87 doctors and 228 nurses completed 315 of 350 (90%) surveys. Doctors and nurses were concerned about infection control, occupational health and safety issues, and environmental waste. Incidents involving spillage of urine and/or blood often go unreported. There were no differences between nurses and doctors having specialist training in urology or experience (P > 0.05). The second major finding is that available catheter packs, particularly drapes, when manipulating IDCs, are inadequate and spillage is likely. These findings were more pronounced in doctors and those with urology training (P < 0.05).CONCLUSIONThe attitudes of health professionals involved with IDC manipulations are consistent with other fields, as is the under‐reporting of episodes of contamination by bodily fluids. The current equipment, particularly drapes, are inadequate for containing urine and blood, leading to infection control, occupational health, environmental and cost implications.