bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resolution of pulmonary interstitial emphysema following selective left main stem intubation in a premature newborn: an old procedure revisited
Authors: CHALAK LINA F. , KAISER JEFFREY R. , ARRINGTON ROBERT W. 
Published: August 2006

SummaryPulmonary interstitial emphysema (PIE) contributes to worsening respiratory status in already compromised premature infants. Various treatments for PIE include high‐frequency ventilation, postural therapy, pneumonectomy or lobectomy and selective bronchial intubation. While right main stem bronchus intubation is easy to perform at the bedside for treatment of PIE in the left lung, left main stem bronchus intubation for the treatment of right‐sided PIE remains challenging and the technique was rarely reported and poorly described.In this case report, we revisit this procedure and describe successful treatment of right lung PIE with hyperinflation by selective left main stem intubation at 2 weeks of life in a 24‐week‐old premature infant who had respiratory distress syndrome and pulmonary hemorrhage. A detailed description is given to allow clinical bedside replication following specific anatomic landmarks.
Atelectasis in children undergoing either propofol infusion or positive pressure ventilation anesthesia for magnetic resonance imaging
Authors: LUTTERBEY GOETZ , WATTJES MIKE P. , DOERR DOROTHEA , FISCHER NICOLAS J. , GIESEKE JUERGEN , SCHILD HANS H. 
Published: August 2006

SummaryBackground: Atelectasis because of anesthesia is a recognized problem but may be affected by the anesthetic technique. We compared magnetic resonance images of atelectasis in children undergoing two types of anesthesia.Methods: Children requiring anesthesia for magnetic resonance imaging (MRI) had additional lung imaging sequences at the beginning and the end of anesthesia. Children had either i.v. propofol infusion (PI) without an artificial airway (n = 26) or positive pressure ventilation (PPV) via a tracheal tube (n = 20); the technique was chosen for clinical reasons. The extent of atelectasis was scored by two independent radiologists.Results: The median ages (range) for PI and PPV groups were 45 months (1–77 months) and 18 months (2–74 months), respectively. The proportion of children with atelectasis was different in the first lung scan (42% vs 80%), but in the second scan atelectasis was seen frequently in both groups (82% vs 94%) with a greater extent in the PPV group. The atelectasis score was higher in young children, but all children had normal oxygen requirements and saturations.Conclusions: Many factors may influence the development of atelectasis but this study found less extensive atelectasis with PI than PPV. PI allows for sufficient motionlessness, required for high diagnostic image quality in pediatric MRI.
Minor increase of endtidal CO2 during sevoflurane‐induced malignant hyperthermia
Authors: BONCIU MONALISA , DE LA CHAPELLE ARNAUD , DELPECH HENRY , DEPRET THIERY , KRIVOSIC‐HORBER RENEÉ , AIMÉ MARC RAUCOULES 
Published: August 2006

SummaryMalignant hyperthermia (MH) in a pediatric patient during sevoflurane anesthesia with only a minor rise of endtidal CO2 is described. MH was considered because of increased rectal temperature. The outcome was favorable after the initiation of a few simple measures (increased minute ventilation, cessation of sevoflurane). As recommended by the regional MH Reference Center, dantrolene was not used. In vitro contracture tests were performed on muscle biopsies from both parents. A strong contracture in response to halothane confirmed the father's MH susceptibility, thereby according a high probability of an MH episode in his son.
Host propagation permits extreme local adaptation in a social parasite of ants
Authors: Schönrogge K. , Gardner M. G. , Elmes G. W. , Napper E. K. V. , Simcox D. J. , Wardlaw J. C. , Breen J. , Barr B. , Knapp J. J. , Pickett J. A. , Thomas J. A. 
Published: August 2006

AbstractThe Red Data Book hoverfly species Microdon mutabilis is an extreme specialist that parasitises ant societies. The flies are locally adapted to a single host, Formica lemani, more intimately than was thought possible in host–parasite systems. Microdon egg survival plummeted in F. lemani colonies > 3 km away from the natal nest, from c. 96% to 0% to < 50%, depending on the hoverfly population. This is reflected in the life‐time dispersal of females, measured at < 2 m, resulting in oviposition back into the same ant nests for generation after generation. To counter destabilizing effects on the host, Microdon manipulates the social dynamics of F. lemani by feeding selectively on ant eggs and small larvae, which causes surviving larvae to switch development into queens. Infested colonies rear double the number of new queens, thus propagating the vulnerable local genotype and compensating for damage to the host colonies. The consequences of such extreme host specificity for insect conservation are discussed.
Decoupling the direct and indirect effects of nitrogen deposition on ecosystem function
Authors: Manning Pete , Newington John E. , Robson Helen R. , Saunders Mark , Eggers Till , Bradford Mark A. , Bardgett Richard D. , Bonkowski Michael , Ellis Richard J. , Gange Alan C. , Grayston Susan J. , Kandeler Ellen , Marhan Sven , Reid Eileen , Tscherko Dagmar , Godfray H. Charles J. , Rees Mark 
Published: August 2006

AbstractElevated nitrogen (N) inputs into terrestrial ecosystems are causing major changes to the composition and functioning of ecosystems. Understanding these changes is challenging because there are complex interactions between ‘direct’ effects of N on plant physiology and soil biogeochemistry, and ‘indirect’ effects caused by changes in plant species composition. By planting high N and low N plant community compositions into high and low N deposition model terrestrial ecosystems we experimentally decoupled direct and indirect effects and quantified their contribution to changes in carbon, N and water cycling. Our results show that direct effects on plant growth dominate ecosystem response to N deposition, although long‐term carbon storage is reduced under high N plant‐species composition. These findings suggest that direct effects of N deposition on ecosystem function could be relatively strong in comparison with the indirect effects of plant community change.
Harvest reserves reduce extinction risk in an experimental microcosm
Authors: Fryxell John M. , Lynn Denis H. , Chris Philip J. 
Published: August 2006

AbstractOverharvesting by humans threatens a substantial fraction of endangered species. Reserves have recently received enormous attention as a means of better conserving harvested resources, despite limited empirical evidence of their efficacy. We used manipulated microcosms to test whether reserves reduce extinction risk in mobile populations of harvested Tetrahymena thermophila, a ciliate. Here we show that patterns of population distribution inside and outside reserves can be accurately predicted on the basis of simple models of diffusion coupled with logistic controls on local population growth. No extinctions occurred in eight experimental trials with reserves, whereas extinction occurred in seven of eight trials without reserves, as predicted by population viability models based on stochastic population processes. These results suggest that marine reserves may be an effective means of improving long‐term viability in heavily harvested fish species.
Land cover associated with hantavirus presence in Paraguay
Authors: Goodin Douglas G. , Koch David E. , Owen Robert D. , Chu Yong‐Kyu , Hutchinson J. M. Shawn , Jonsson Colleen B. 
Published: August 2006

ABSTRACTAims Hantaviruses are zoonotic, aetiological agents maintained by rodents of the family Muridae. The occurrence of hantavirus in rodent hosts has been correlated to a number of climatic and environmental factors, including landscape structure. To date, most of these correlative studies have been conducted at moderate to fine spatial resolution. Our aim is to determine whether land cover classes defined at a mapping resolution of 1 km2are associated with rodents with antibodies to hantavirus in Paraguay.Location The Republic of Paraguay.Methods A total of 362 rodents from 10 species known to host hantaviruses were tested for the presence of hantavirus antibodies, resulting in 27 seropositive individuals. This data base was then combined with a map of six land cover types derived from coarse resolution remote sensing data to create a series of contingency tables, which were used to relate serostatus to land cover type using nonparametric tests of proportions and qualitative comparison of observed and expected values.Results There was a significant difference in habitat association between seropositive and seronegative rodents when species were pooled. Seropositive rodents were found with disproportionately high frequency in areas where human disturbance in the form of intensive and mosaic agricultural landscapes was present.Main conclusions Human‐disturbed land cover classes have a detectable relationship to the hantavirus serostatus of host population rodents when observed at coarse spatial resolutions. Although coarse‐grained analysis does not lead to any conclusions as to why agricultural land cover is more likely to harbour seropositive rodents, the relationship between them could form the basis for a monitoring system designed to relate land cover change to potential viral outbreaks in rodents and humans.
The Balassa–Samuelson Effect in a Developing Country
Authors: Gente Karine 
Published: August 2006

AbstractSome Asian countries experience small real exchange rate appreciations or even a real depreciation despite a fast growth in tradable productivity. A key‐characteristic of these countries is that they are constrained on capital inflows. Is the Balassa–Samuelson theory still valid in those countries? Are there other factors likely to explain real exchange rate (RER) changes? To address these questions, we develop a two‐sector model in which a small open economy faces a constraint on capital inflows. In this setting, the RER does not only depend on productivity, but also on other factors like the rate of time preference, the age dependency ratio or the level of the external constraint. A calibration of the constrained economy model seems to match at least qualitatively empirical evidence for China, Hong Kong, Indonesia, Malaysia, Thailand, and Singapore, between 1970 and 1992.
Use of a ROSA26:GFP transgenic line for long‐term Xenopus fate‐mapping studies
Authors: Gross Joshua B. , Hanken James , Oglesby Ericka , Marsh‐Armstrong Nicholas 
Published: August 2006

AbstractWidespread and persistent marker expression is a prerequisite for many transgenic applications, including chimeric transplantation studies. Although existing transgenic tools for the clawed frog, Xenopus laevis, offer a number of promoters that drive widespread expression during embryonic stages, obtaining transgene expression through metamorphosis and into differentiated adult tissues has been difficult to achieve with this species. Here we report the application of the murine ROSA26 promoter in Xenopus. GFP is expressed in every transgenic tissue and cell type examined at post‐metamorphic stages. Furthermore, transgenic ROSA26:GFP frogs develop normally, with no apparent differences in growth or morphology relative to wild‐type frogs. ROSA26 transgenes may be used as a reliable marker for embryonic fate‐mapping of adult structures in Xenopus laevis. Utility of this transgenic line is illustrated by its use in a chimeric grafting study that demonstrates the derivation of the adult bony jaw from embryonic cranial neural crest.
Regional variations in the density and arrangement of elastic fibres in the anulus fibrosus of the human lumbar disc
Authors: Smith Lachlan J. , Fazzalari Nicola L. 
Published: August 2006

AbstractElastic fibres are critical components of the extracellular matrix in dynamic biological structures that undergo extension and recoil. Their presence has been demonstrated in the anulus fibrosus of the human lumbar intervertebral disc; however, a detailed regional analysis of their density and arrangement has not been undertaken, limiting our understanding of their structural and functional roles. In this investigation we have quantitatively described regional variations in elastic fibre density in the anulus fibrosus of the human L3–L4 intervertebral disc using histochemistry and light microscopy. Additionally, a multiplanar comparison of patterns of elastic fibre distribution in the intralamellar and interlamellar zones was undertaken. Novel imaging techniques were developed to facilitate the visualization of elastic fibres otherwise masked by dense surrounding matrix. Elastic fibre density was found to be significantly higher in the lamellae of the posterolateral region of the anulus than the anterolateral, and significantly higher in the outer regions than the inner, suggesting that elastic fibre density in each region of the anulus is commensurate with the magnitude of the tensile deformations experienced in bending and torsion. Elastic fibre arrangments in intralamellar and interlamellar zones were shown to be architecturally distinct, suggesting that they perform multiple functional roles within the anulus matrix structural hierarchy.
The postnatal development of cerebellar Purkinje cells in the Göttingen minipig estimated with a new stereological sampling technique – the vertical bar fractionator
Authors: Jelsing Jacob , Gundersen Hans Jørgen G. , Nielsen Rune , Hemmingsen Ralf , Pakkenberg Bente 
Published: August 2006

AbstractThe postnatal development of total number and perikaryon volume of cerebellar Purkinje cells was estimated in the Göttingen minipig cerebellar cortex using a new stereological approach, the vertical bar fractionator. Data were obtained from the brains of five neonate and five adult female Göttingen minipigs. The total number of Purkinje cells ranged from 1.83 × 106 in the neonate to 2.82 × 106 in the adult Göttingen minipig. The number‐weighted mean perikaryon volume of Purkinje cells increased concurrently from around 6800 µm3 in the neonate to 17 600 µm3 in the adult. The study demonstrates that a pronounced postnatal neurogenesis in Purkinje cell number and perikaryon volume is part of the growth and development of the cerebellum in the Göttingen minipig. The Purkinje cells of the Göttingen minipig were found to be substantially large compared with human and represents the largest cells described hitherto from mammalian cerebella. The vertical fractionator is a new sampling technique, which allows the combination of a fractionator design on vertical bar sections excluding exhaustive sampling and bias from artificial edges. By design, the sections are perfect stereological vertical sections and provide the basis for unbiased estimates of total number of structural entities in the brain, including surface area, fibre length and particle volume.
Prediction of volumetric strain in the human temporomandibular joint cartilage during jaw movement
Authors: Koolstra J. H. , Van Eijden T. M. G. J. 
Published: August 2006

AbstractHuman temporomandibular joint loading causes pressurization and flow of interstitial fluid in its cartilaginous structures. This largely determines its load‐bearing and maintenance capacity. It was hypothesized that during cyclical jaw movements normal pressure distribution dynamics would enable fluid to reach all necessary cartilage regions. This was tested qualitatively by analysis of local volumetric strain dynamics during jaw open–close movements predicted by a dynamic model of the human masticatory system. Finite‐element analysis was performed in separate regions of the articular cartilage layers and articular disc. Heterogeneous patterns of dilatation and compression were predicted. Compression was found to be more dominant during jaw closing than opening. The pressure gradient in the superior layer of the articular disc was more mediolaterally orientated than in its inferior layer. The findings suggest that, where necessary, regionally the cartilage can imbibe fluid to protect the subchondral bone from impact loads effectively. In the disc itself presumably all areas receive regular refreshment of interstitial fluid.
The zona pellucida of the koala (Phascolarctos cinereus): its morphogenesis and thickness
Authors: Chapman Jamie A. , Leigh Christopher M. , Breed William G. 
Published: August 2006

AbstractIn this study the ultrastructural organization of the koala oocyte and the thickness of the surrounding extracellular coat, the zona pellucida, has been determined to ascertain whether there is coevolution of the morphology of the female gamete with that of the highly divergent male gamete that is found in this marsupial species. Ovaries from several adult koalas were obtained and prepared for transmission electron microscopy. Oocytes in large tertiary follicles were somewhat smaller than those of most other marsupials, although their ultrastructural organization appeared similar and included many yolk vesicles. The zona pellucida surrounding the oocytes in tertiary follicles was approximately 8 µm thick and thus is of similar thickness to that of some eutherian mammals but at least twice as thick as that of most marsupial species so far studied. The results indicate that the koala oocyte is unusually small for a marsupial species whereas the zona pellucida is, by contrast, much thicker. How this relates to sperm–egg interaction at the time of fertilization has yet to be determined.
Differential availability/processing of decorin precursor in arterial and venous smooth muscle cells
Authors: Franch Rafaella , Chiavegato Angela , Maraschin Maddalena , Candeo Serena , Ausoni Simonetta , Villa Antonello , Gerosa Gino , Gasparotto Lisa , Parnigotto Pierpaolo , Sartore Saverio 
Published: August 2006

AbstractThe existence of specific differentiation markers for arterial smooth muscle (SM) cells is still a matter of debate. A clone named MM1 was isolated from a library of monoclonal antibodies to adult porcine aorta, which in vivo binds to arterial but not venous SM cells, except for the pulmonary vein. MM1 immunoreactivity in Western blotting involved bands in the range of Mr 33–226 kDa, in both arterial and venous SM tissues. However, immunoprecipitation experiments revealed that MM1 bound to a 100‐kDa polypeptide that was present only in the arterial SM extract. By mass spectrometry analysis of tryptic digests from MM1‐positive 130‐ and 120‐kDa polypeptides of aorta SM extract, the antigen recognized by the antibody was identified as a decorin precursor. Using a crude decorin preparation from this tissue MM1 reacted strongly with the 33‐kDa polypeptide and this pattern did not change after chondroitinase ABC treatment. In vitro, decorin immunoreactivity was found in secreted grainy material produced by confluent arterial SM cells, although lesser amounts were also seen in venous SM cells. Western blotting of extracts from these cultures showed the presence of the 33‐kDa band but not of the high‐molecular‐weight components, except for the 100‐kDa monomer. The 100/33‐kDa combination was more abundant in arterial SM cells than in the venous counterpart. In the early phase of neointima formation, induced by endothelial injury of the carotid artery or vein‐to‐artery transposition, the decorin precursor was not expressed, but it was up‐regulated in the SM cells of the media underlying the neointima in both models. Collectively, these data suggest a different processing/utilization of the 100‐kDa monomer of proteoglycan decorin in arterial and venous SM cells, which is abolished after vein injury.
Functional anatomy of interhemispheric cortical connections in the human brain
Authors: Zarei Mojtaba , Johansen‐Berg Heidi , Smith Steve , Ciccarelli Olga , Thompson Alan J. , Matthews Paul M. 
Published: August 2006

AbstractInterhemsipheric interaction between the human cerebral hemispheres is served by abundant white‐matter fibres in the human corpus callosum (CC). Damage to these fibres has notable behavioural and cognitive sequelae that depend on the exact location of the fibre loss. Until now, correlations between fibre loss and neurological disorders have been limited to post‐mortem studies. Here we used probabilistic diffusion magnetic resonance imaging tractography to produce a two‐dimensional map of the CC in the mid‐sagittal plane. We observed an antero‐posterior topography of interhemispheric tracts within the CC, consistent with our current neuroanatomical understanding of post‐mortem studies in human. Callosal tract to the left and right hemispheres had comparable volume. Gender, a factor that is often reported to affect CC shape and geometry, also had no effect on the volume of the tracts. Our map showed high consistency across individuals. We propose that this map might be useful in the study of the effects of damage to human CC in neurodegenerative and cognitive disorders.
Evidence of solitary chemosensory cells in a large mammal: the diffuse chemosensory system in Bos taurus airways
Authors: Tizzano Marco , Merigo Flavia , Sbarbati Andrea 
Published: August 2006

AbstractThe diffuse chemosensory system (DCS) of the respiratory apparatus is composed of solitary chemosensory cells (SCCs) that resemble taste cells but are not organized in end organs. The discovery of the DCS may open up new approaches to respiratory diseases. However, available data on mammalian SCCs have so far been collected from rodents, the airways of which display some differences from those of large mammals. Here we investigated the presence of the DCS and of SCCs in cows and bulls (Bos taurus), in which the airway cytology is similar to that in humans, focusing our attention on detection in the airways of molecules involved in the transduction cascade of taste [i.e. α‐gustducin and phospholipase C of the β2 subtype (PLCβ2)]. The aim of the research was to extend our understanding of airway chemoreceptors and to compare the organization of the DCS in a large mammal with that in rodents. Using immunocytochemistry for α‐gustducin, the taste buds of the tongue and arytenoid were visualized. In the trachea and bronchi, α‐gustducin‐immunoreactive SCCs were frequently found. Using immunocytochemistry for PLCβ2, the staining pattern was generally similar to those seen for α‐gustducin. Immunoblotting confirmed the expression of α‐gustducin in the tongue and in all the airway regions tested. The study demonstrated the presence of SCCs in cows and bulls, suggesting that DCSs are present in many mammalian species. The description of areas with a high density of SCCs in bovine bronchi seems to indicate that the view of the DCS as made up of isolated cells totally devoid of ancillary elements is probably an oversimplification.