bluuebunny/crossref_metadata_2025 huggingface dataset:
Inter‐ and intraobserver reproducibility of thyroid fine needle aspiration cytology: an analysis of discrepant cases
Authors: Gerhard R. , Da Cunha Santos G.
Published: January 2007

Objective:  To determine the inter‐ and intraobserver reproducibility and analyse the discrepant cases of fine needle aspiration cytology (FNAC) of the thyroid.

Methods:  Cases of thyroid FNAC with a corresponding histological diagnosis were reviewed regarding the original cytological diagnoses by two observers. The final cytological diagnoses (FCD) included both concordant and consensus diagnoses. The inter‐ and intraobserver reproducibility and efficacy of thyroid FNAC were calculated based on the FCD.

Results:  A total of 97 FNAC cases with corresponding histopathological specimens were analysed. Although inter‐ and intraobserver disagreement in the cytological diagnoses occurred in about one‐quarter of the cases analysed (24.7% and 23.7%, respectively), a substantial level of diagnostic interobserver (kappa = 0.71) and intraobserver (kappa = 0.66) reproducibility was observed. The efficacy of the method was 94.4%. Disagreement in the diagnosis was detected in 24 cases (24.7%), most of them (41.7%) for follicular lesions. Discordant cytological diagnoses between the two observers were represented by six (16.2%) of the 37 cases with an FCD of colloid nodule, five (41.7%) of the 12 cases of cellular follicular lesion, all three cases of follicular neoplasm, in two (6.3%) of the 32 cases of PTC, one (16.7%) of six cases of follicular neoplasm with a predominance of Hürthle cells and in one case of poorly differentiated neoplasia. Similarly, major disagreement in intraobserver cytological diagnoses was observed for the diagnosis of follicular lesions: 18 (78.3%) of a total of 23 discordant cases.

Conclusion:  As discrepancies in the cytopathological diagnosis can have repercussions in the management of patients, all cases with a cytological diagnosis of follicular lesions/neoplams should be reviewed in multidisciplinary meetings thus minimizing interobserver variability.
Anchovy (Engraulis ringens) and sardine (Sardinops sagax) spatial dynamics and aggregation patterns in the Humboldt Current ecosystem, Peru, from 1983–2003
Authors: GUTIÉRREZ MARIANO , SWARTZMAN GORDON , BERTRAND ARNAUD , BERTRAND SOPHIE
Published: January 2007

Three indexes of spatial aggregation are developed and used to examine the aggregation pattern of sardine (Sardinops sagax) and anchovy (Engraulis ringens) in the Peruvian Humboldt Current System, determined from 36 acoustic surveys conducted from 1983 through 2003 by the Peruvian Marine Institute (IMARPE). Each index assesses a different aspect of aggregation: the concentration, the percent occupancy of space and the clustering of high‐fish abundance. Both time‐series correlation and tree‐based clustering‐regression method, classification and regression trees (CART), were used to relate each of the indexes to environmental variables (season, temperature anomaly and year). Additionally, a measure of onshore–offshore distribution, the average distance from the coast, and abundance variables (the average acoustic backscatter per occupied sampling unit, and the acoustically estimated total abundance of sardine and anchovy from IMARPE) were related to environmental factors by using CART. We show that the 1983–2003 time series can be divided into three different periods: with shifts in 1992 and in 1997–98. Sardine and anchovy showed large differences in both abundance and aggregation among these periods. Although upwelling ecosystems support dramatic and sudden changes in environmental conditions, fish responses are sometimes smoother than usually suggested and there are transition periods with concomitant high biomasses of anchovy and sardine, but with different spatial aggregation patterns. Observed relationships between environmental proxies and aggregation patterns support the habitat‐based hypothesis that environmentally mediated alterations in range lead to population changes.
Efficacy, safety and tolerability of recombinant factor VIII (REFACTO®) in patients with haemophilia A: interim data from a postmarketing surveillance study in Germany and Austria
Authors: POLLMANN H. , EXTERNEST D. , GANSER A. , EIFRIG B. , KREUZ W. , LENK H. , PABINGER I. , SCHRAMM W. , SCHWARZ T. F. , ZIMMERMANN R. , ZAVAZAVA N. , OLDENBURG J. , KLAMROTH R.
Published: January 2007

Summary.  An open‐label, multicentre, postmarketing surveillance study conducted in Germany and Austria with recombinant factor VIII (REFACTO®) has enrolled 217 patients (mean age 26.3 years) from 38 haemophilia centres during the first 4.8 years. Most patients (188/217; 86.6%) had severe to moderately severe haemophilia A, of whom 153 completed sufficient diary information for the main efficacy analysis. These 153 patients experienced a median of 6.6 (interquartile range 1.4–18.6) bleeding episodes per year. Patients treated with prophylaxis experienced a median of 4.4 (1.1–9.3) bleeds per year, while patients treated on‐demand experienced a median of 22.8 (11.3–29.0) bleeds per year. Overall, most physicians (41/43 [95.3%]) were ‘very satisfied’ or ‘satisfied’ with the efficacy of REFACTO in the treatment of bleeding episodes. A total of 137 non‐serious adverse events have been reported in 52/217 patients (24.0%) to date. In addition, 129 serious adverse events in 87 patients (40%) were reported, including 41 cases of ‘less than expected therapeutic effect’ (LETE). Of these, 39 LETE cases were reported in one centre; however, patients in this centre experienced considerably fewer bleeding episodes per year than patients outside this centre. Overall, six patients (2.8%) have developed de novo inhibitors, three of which were considered high titre. Four of these patients were at high risk (0–50 exposure days [ED]) of inhibitor formation, one was at intermediate risk (51–100 ED) and one was at low risk (>100 ED). These results emphasize the benefit of postmarketing surveillance and, overall, this study confirms the efficacy, safety and tolerability of REFACTO in the treatment of patients with haemophilia A.
Inhibitor development in one patient and laboratory discrepancies in several families with both mild haemophilia and Arg531Cys mutation
Authors: CID A. R. , CASAÑA P. , CABRERA N. , HAYA S. , CORTINA V. , AZNAR J. A.
Published: January 2007

Summary.  Certain mutations in mild haemophilia A have been associated with a greater risk of inhibitor development, especially when associated with intense treatment. We present a patient with both mild haemophilia A and Arg531Cys mutation, which developed lowtitre inhibitors and was not seen to be related to the intense substitute treatment. The inhibitor has a greater effect on the exogenous factor VIII, permiting an adequate response to treatment with desmopressin. A discrepancy exists in the factor VIII activity in this our patient and in the haemophiliacs of another two families with the same mutation when determination is performed with one‐stage or chromogenic method.
Successful combination therapy of a proximal haemophilic pseudotumour with surgery, radiation and embolization in a child with mild haemophilia A
Authors: AHUJA S. P. , SIDONIO R. , RAJ A. B. , BERTOLONE S. J. , SILVERMAN C. , ANTEKEIER D. P. , FALLAT M. E.
Published: January 2007

Summary.  We describe the management of a young boy with mild haemophilia A and a massive iliac pseudotumour with a multi modality approach involving factor replacement, radiation therapy, embolization and surgery. The patient was initially treated with recombinant factor VIII and radiation therapy. Because of inadequate response and worsening of bony erosion, the patient had a preoperative embolization followed by surgical excision. The surgical procedure was associated with minimal blood loss and the patient had a relatively smooth postoperative course with no physical morbidity. This case illustrates successful aggressive management of a large, proximally located pelvic pseudotumour, which resulted in an excellent outcome despite the need for a normally morbid operation.
The significance of VEGF‐C/VEGFR‐2 interaction in the neovascularization and prognosis of nephroblastoma (Wilms' tumour)
Authors: Nowicki M , Ostalska‐Nowicka D , Kaczmarek M , Miskowiak B , Witt M
Published: January 2007

Aim:  To investigate the immunohistochemical expression of vascular endothelial growth factor (VEGF)‐C and VEGFR‐2 in nephroblastoma tissue and correlate their presence with the survival rate of children diagnosed with stage III Wilms' tumour.

Methods and results:  The material included nephroblastoma tissue obtained from 25 children hospitalized in the Department of Paediatric Oncology, Haematology and Transplantology between 1997 and 2003. VEGF‐C and VEGFR‐2 expression was evaluated by immunohistochemical assay. VEGF‐C was expressed in all cells of the blastemal component and in 30% of tumour cells in the stromal part. It was absent from epithelial elements. VEGFR‐2 expression was spread over the surface of numerous stromal cells as well as all the epithelial cells forming dysplastic tubules. The blastemal component of Wilms' tumour was VEGFR‐2‐negative. VEGF‐C‐immunopositive stromal cells were situated in the closest proximity to VEGF‐C‐immunonegative but VEGFR‐2‐immunoreactive tubules. VEGF‐C expression was of prognostic value for both clinical progression (P = 0.0005) and tumour‐related death (P = 0.0365).

Conclusions:  VEGF‐C expression in Wilms' tumour constitutes a potent unfavourable risk factor and may direct future antiangiogenic treatment strategies. The proximity of VEGF‐C and VEGFR‐2 in the stromal and epithelial components of nephroblastoma could be the neoplastic equivalent of the binary VEGF‐C function observed in epithelial and endothelial morphogenesis.
Location‐specific sympatric morphological divergence as a possible response to species interactions in West VirginiaPlethodonsalamander communities
Authors: ADAMS DEAN C. , WEST MARY E. , COLLYER MICHAEL L.
Published: January 2007

The competitive interactions of closely related species have long been considered important determinants of community composition and a major cause of phenotypic diversification. However, while patterns such as character displacement are well documented, less is known about how local adaptation influences diversifying selection from interspecific competition.

We examined body size and head shape variation among allopatric and sympatric populations of two salamander species, the widespreadPlethodon cinereusand the geographically restrictedP. nettingi. We quantified morphology from 724 individuals from 20 geographical localities throughout the range ofP. nettingi.

Plethodon nettingiwas more robust in cranial morphology relative toP. cinereus, and sympatric localities were more robust relative to allopatric localities. Additionally, there was significantly greater sympatric head shape divergence between species relative to allopatric communities, and sympatric localities ofP. cinereusexhibited greater morphological variation than sympatricP. nettingi.

The sympatric morphological divergence and increase in cranial robustness of one species (P. nettingi) were similar to observations in otherPlethodoncommunities, and were consistent with the hypothesis of interspecific competition. These findings suggest that interspecific competition inPlethodonmay play an important role in phenotypic diversification in this group.

The increase in among‐population variance in sympatricP. cinereussuggests a species‐specific response to divergent natural selection that is influenced in part by other factors. We hypothesize that enhanced morphological flexibility and ecological tolerance allowP. cinereusto more rapidly adapt to local environmental conditions, and initial differences among populations have allowed the evolutionary response ofP. cinereusto vary across replicate sympatric locations, resulting in distinct evolutionary trajectories of morphological change.
Should biomass be considered more frequently as a currency in terrestrial arthropod community analyses?
Authors: SAINT‐GERMAIN MICHEL , BUDDLE CHRISTOPHER M. , LARRIVÉE MAXIM , MERCADO ALIDA , MOTCHULA TANIA , REICHERT ELISABETH , SACKETT TARA E. , SYLVAIN ZACHARY , WEBB ANNIE
Published: January 2007

Community structure involving large taxonomical groups is frequently used to assess changes in ecosystems along environmental gradients or in response to disturbance. For terrestrial arthropods, abundance is generally used as the response variable in community data analyses; biomass, however, is generally a better indicator of the functionality of a species within a community, as it is strongly correlated with metabolism.

In this study, we considered whether biomass should be used more often in community analyses with terrestrial arthropod biodiversity data, particularly when asking questions involving strong functional components. We selected 10 previously published and five unpublished Coleoptera abundance data sets, and produced biomass species‐by‐sample matrices using body length to body mass conversion equations, and then compared the results obtained using commonly used ecological analyses.

Correlations between species abundance and biomass varied from strong to poor, depending on the taxa considered and on the sampling method used. We show that abundance and biomass can produce different results in community data analysis and lead to alternative interpretations for data sets with poor abundance to biomass correlations.

Synthesis and applications. When dealing with databases showing poor abundance to biomass relationships, the question of the relevance of using biomass instead of abundance emerges, and the choice of the response variable to be used in analyses should be considered carefully. At the very least, when studying terrestrial arthropod biodiversity, one should consider the use of biomass with simple conversion equations that do not require obtaining the mass of individual specimens. This approach may lead to different interpretations. For research questions in which trophic interactions may play an important role, biomass may provide a broader and more accurate picture of the processes driving changes in community structure.
How landscape structure, land‐use intensity and habitat diversity affect components of total arthropod diversity in agricultural landscapes
Authors: HENDRICKX FREDERIK , MAELFAIT JEAN‐PIERRE , VAN WINGERDEN WALTER , SCHWEIGER OLIVER , SPEELMANS MARJAN , AVIRON STÉPHANIE , AUGENSTEIN ISABEL , BILLETER REGULA , BAILEY DEBRA , BUKACEK ROMAN , BUREL FRANÇOISE , DIEKÖTTER TIM , DIRKSEN JOLANDA , HERZOG FELIX , LIIRA JAAN , ROUBALOVA MARTINA , VANDOMME VIKI , BUGTER ROB
Published: January 2007

Agricultural intensification poses a serious threat to biodiversity as a consequence of increased land‐use intensity, decreased landscape heterogeneity and reduced habitat diversity. Although there is interest in the preservation of total species richness of an agricultural landscape (γ diversity), the effects of intensification have been assessed primarily by species richness at a local scale (α diversity). This ignores species richness between local communities (β diversity), which is an important component of total species richness.

In this study, measures of land‐use intensity, landscape structure and habitat diversity were related to γ, α and β diversity of wild bees (Apoidea), carabid beetles (Carabidae), hoverflies (Syrphidae), true bugs (Heteroptera) and spiders (Araneae) within 16 local communities in 24 temperate European agricultural landscapes.

The total landscape species richness of all groups was most strongly affected by increased proximity of semi‐natural habitat patches. Bees also decreased in landscapes with a high intensity of farmland management, demonstrating additive effects of both factors.

Separating total species diversity into components, the decrease in total species richness could be attributed primarily to a decrease in species diversity between local communities. Species richness of the local communities of all investigated groups decreased with increasing land‐use intensity and, in the case of spiders, decreasing proximity of the semi‐natural habitat patches.

The effect of increased habitat diversity appeared to be of secondary importance to total species richness but caused a shift in the relative contribution of α and β diversity towards the latter.

Synthesis and applications. This study demonstrates that the effects of agricultural change operate at a landscape level and that examining species diversity at a local level fails to explain the total species richness of an agricultural landscape. The coincidence of patterns of β diversity with those of γ diversity emphasizes that such information is of crucial importance for the implementation and evaluation of restoration programmes aiming to restore sustainable countryside diversity. As local extinction processes in highly fragmented landscapes shape biodiversity, priority should be given to the conservation of diverse agricultural landscape remnants in Europe.
Using potential distributions to explore determinants of Western Palaearctic migratory songbird species richness in sub‐Saharan Africa
Authors: Wisz M. S. , Walther B. A. , Rahbek C.
Published: January 2007

Aim  Although the breeding ranges of most Western Palaearctic migratory passerines are well documented in Europe, their overwintering ranges and patterns of species richness in Africa remain poorly understood. To illustrate potential patterns of species richness despite severely limited data, we extrapolated species ranges from a new and unique data bank of locality records that documents overwintering locations of these birds in Africa.

Location  Sub‐Saharan Africa.

Methods  We predicted potential geographical distributions of 60 species of passerine birds based on overwintering records using bioclimatic models. We then combined these predictions to estimate potential species richness and explored response shapes using spatial linear regression. We also evaluated the evidence for a mid‐domain effect using a one‐dimensional null model.

Results  Spatial linear regression analyses of the species richness pattern revealed non‐linear relationships to seasonality in precipitation, minimum net primary productivity, minimum average temperature, habitat heterogeneity, percentage of tree cover, distance from the Sahara Desert and inter‐annual variability in net primary productivity. The explanatory power of these variables decreased with geographic range size. The one‐dimensional null model of species richness based on distance from the Sahara Desert did not show evidence of a mid‐domain effect.

Main conclusions  Distributions of migrants seem generally strongly determined by distance from the Sahara Desert working in concert with climatic effects, but this cannot adequately explain richness patterns of species with small ranges in Africa, many of which are of substantial conservation concern.
An operational, additive framework for species diversity partitioning and beta‐diversity analysis
Authors: PÉLISSIER RAPHAËL , COUTERON PIERRE
Published: January 2007

An important goal of community ecology is the assessment of factors that are likely to influence the spatio‐temporal distribution of species assemblages and diversity. Surprisingly, most statistical methods devoted to this have remained poorly interconnected, as well as poorly connected with the popular metrics of diversity estimation. In the present paper we show that important questions related to determinants of species diversity can be specified through a simple multivariate linear model and explored, in common diversity metrics, using standard methods and routines of variance/covariance decomposition.

Thanks to an unusual form of presentation of taxonomic data into a table of species occurrences, which considers the individuals as data units, Shannon and Simpson indices as well as species richness can all be expressed as a (weighted) sum of squares. Subsequent apportionments into explained and residual sum of squares provide direct estimates of the beta‐ and alpha‐diversity components with respect to either categorical habitat types or continuous gradient variables. Appropriate statistics and non‐parametric tests are available to assess the significance of these components.

Explicit analytical relationships exist between the linear approximation of the table of species occurrences by sampling sites, and the more classical table of species abundances by sites. Therefore, direct links with methods of ordination in reduced space, such as correspondence analysis and canonical correspondence analysis, provide opportunities for partitions that preserve consistency with usual diversity indices. The sum of squares of the approximated occurrence table provides measures of intersites beta‐diversity, from which measures of dissimilarity with explicit references to diversity indices can be derived. Such measures are amenable to distance‐based apportionments through multivariate variograms and multiscale ordination.

What are the relative effects of the biological, environmental and anthropogenic factors and of their potential interactions on species diversity? Are these effects stable across scales, from landscape to region, between regions and across ecosystems? The methodological integration proposed in our analytical framework enables one to address these questions using standard statistical tools, and opens new prospects for quantitative biodiversity studies. This also paves the way towards refined models for predicting species diversity at unsampled locations.
Rosiglitazone and carotid IMT progression rate in a mixed cohort of patients with type 2 diabetes and the insulin resistance syndrome: main results from the Rosiglitazone Atherosclerosis Study
Authors: Hedblad B. , Zambanini A. , Nilsson P. , Janzon L. , Berglund G.
Published: January 2007

Objective.  Insulin resistance is associated with progression of atherosclerosis. We assessed the effect of 12 months of treatment with rosiglitazone (RSG) on the progression of carotid intima–media thickness (IMT) in people with type 2 diabetes mellitus (T2DM) or the insulin resistance syndrome (IRS).

Design.  Randomized, double‐blind, placebo‐controlled trial.

Setting.  Malmö University Hospital, Malmö, Sweden.

Subjects.  555 subjects (200 with T2DM and 355 nondiabetics with IRS according to EGIR criteria), aged 35–80 years. 447 subjects (165 T2DM and 282 IRS) completed the study.

Intervention.  Participants were allocated to placebo or RSG 4 mg for 2 months and then 8 mg daily.

Main outcome measure.  Change in composite IMT [mean IMT in the common carotid artery (CCA) and maximal IMT in the bulb] was the primary and various other IMT measures were secondary outcome variables.

Results.  There was no effect of RSG treatment in the mixed population. In T2DM patients there was a reduced progression of the composite IMT (mean change: 0.041 vs. 0.070 mm, P = 0.07), and of the mean IMT CCA (mean change: −0.005 mm vs. 0.021 mm, P = 0.007). RSG treatment led to significant reductions of HOMA‐IR, fasting plasma glucose, HbA1c, PAI‐1 activity, fibrinogen, C‐reactive protein and matrix metalloproteinase‐9.

Conclusions.  In a mixed study population of patients with T2DM and IRS RSG treatment was not associated with a statistically significant reduction of carotid IMT progression rate. Separate analyses of these two patient groups indicated, however, a significant beneficial effect on CCA IMT in T2DM patients but no similar effect in subjects with IRS.
The effects of temperature, body mass and feeding on metabolic rate in the tsetse flyGlossina morsitans centralis
Authors: TERBLANCHE JOHN S. , CHOWN STEVEN L.
Published: January 2007

AbstractMetabolic rate variation with temperature, body mass, gender and feeding status is documented forGlossina morsitans centralis. Metabolic rate [mean ± SE; VCO2= 19.78 ± 3.11 μL CO2h−1in males (mean mass = 22.72 ± 1.41 mg) and 27.34 ± 3.86 μL CO2h−1in females (mean mass = 29.28 ± 1.96 mg) at 24 °C in fasted individuals] is strongly influenced by temperature, body mass and feeding status, but not by gender once the effects of body mass have been accounted for. A significant interaction between gender and feeding status is seen, similar to patterns of metabolic rate variation documented inGlossina morsitans morsitans. Synthesis of metabolic rate‐temperature relationships inG. m. centralis,G. m. morsitansandGlossina pallidipesindicate that biting frequency as well as mortality risks associated with foraging will probably increase with temperature as a consequence of increasing metabolic demands, although there is little evidence for variation among species at present. Furthermore, metabolic rate–body mass relationships appear to be similarly invariant among these species. These data provide important physiological information for bottom‐up modelling of tsetse fly population dynamics.
The fluorouridine insensitive 1 (fur1) mutant is defective in equilibrative nucleoside transporter 3 (ENT3), and thus represents an important pyrimidine nucleoside uptake system in Arabidopsis thaliana
Authors: Traub Michaela , Flörchinger Martin , Piecuch Jennifer , Kunz Hans‐Henning , Weise‐Steinmetz Alexandra , Deitmer Joachim W. , Ekkehard Neuhaus H. , Möhlmann Torsten
Published: January 2007

The fluorouridine insensitive 1 (fur1) locus in Arabidopsis thaliana (L.) Heynh. has previously been identified in a screen for growth resistance towards the toxic compound fluorouridine. Mutation of this locus by ethylmethane sulfonate (EMS) allows mutants to grow on this uridine analogue. We identified that the A. thaliana equilibrative nucleoside transporter (AtENT3) was encoded by the fur1 locus. T‐DNA insertional mutant plants for AtENT3 resemble the fur1 mutant phenotype: i.e. they grow on fluorouridine, and seedlings as well as leaf discs exhibit a markedly reduced uptake capacity for uridine and cytidine, but a less pronounced reduced uptake for adenosine and guanosine. These results indicate that AtENT3 is an important pyrimidine nucleoside transporter in Arabidopsis. In addition, we identified the mutation in fur1 as a single base‐pair exchange, guanine → adenine, leading to an amino acid exchange G → R at position 281. Furthermore, we showed that this mutation is indeed responsible for the observed alterations in nucleoside transport in the fur1‐1 line, because the introduction of this mutation in AtENT3 promoted fluorouridine resistance in yeast cells expressing this mutated protein. The biochemical characterization of AtENT3 expressed in Xenopus oocytes identified a proton‐coupled concentrative mode of nucleoside transport, although this carrier possesses structural features characteristic for equilibrative nucleoside carriers.
EDM2 is required for RPP7‐dependent disease resistance in Arabidopsis and affects RPP7 transcript levels
Authors: Eulgem Thomas , Tsuchiya Tokuji , Wang Xiao‐Jun , Beasley Britt , Cuzick Alayne , Tör Mahmut , Zhu Tong , McDowell John M. , Holub Eric , Dangl Jeffery L.
Published: January 2007

Specific disease resistance of Arabidopsis thaliana against the Hyaloperonospora parasitica isolate Hiks1 (HpHiks1) is mediated by RPP7. Although this disease resistance gene encodes a typical nucleotide binding site leucine‐rich repeat (NB‐LRR) disease resistance protein, its function is independent of the defense hormone salicylic acid and most known genes required for plant immune responses. We identified EDM2 (enhanced downy mildew 2) in a genetic screen for RPP7 suppressors. Mutations of EDM2 phenocopy RPP7 mutations, but do not affect other tested disease resistance genes. We isolated EDM2 by map‐based cloning. The predicted EDM2 protein is structurally unrelated to previously identified components of the plant immune system, bears typical features of transcriptional regulators, including plant homeodomain (PHD)‐finger‐like domains, and defines a plant‐specific protein family. In edm2 mutants both constitutive and HpHiks1‐induced RPP7 transcript levels are reduced, suggesting that EDM2 is either a direct or an indirect regulator of RPP7 expression. Microarray analyses defined a set of defense‐associated genes, the expression of which is suppressed during successful HpHiks1 colonization of either rpp7 or edm2 plants. This transcriptional phenotype is counteracted by an EDM2/RPP7‐dependent mechanism.
Repeat percutaneous dilatational tracheostomy in an awake and unintubated patient
Authors: Rashid A. , Raj B. , Stoddart A.
Published: January 2007

Bedside percutaneous dilatational tracheostomy (PDT) has become an accepted method for securing airways in patients requiring prolonged ventilatory support. Repeat PDT in patients who have had a tracheostomy earlier is considered a relative contraindication as a result of distorted anatomy. Three case series have been reported supporting the safety of repeat bedside PDT in experienced hands, but there is no previously published data regarding repeat PDT in awake and unintubated patients. We report a case in which a repeat PDT was done on an awake 20‐year‐old female patient with cerebral palsy and kyphoscoliosis admitted owing to pneumonia and respiratory failure. This facilitated tracheal toilet in this patient without resorting to general anaesthesia and mechanical ventilation. In conclusion, both repeat PDT and awake PDT, both separately or together, can be very useful in the management of critical care and pre‐critical care patients and merit wider use.
Resource‐dependent sex‐allocation in a simultaneous hermaphrodite
Authors: VIZOSO D. B. , SCHÄRER L.
Published: January 2007

Most sex allocation theory is based on the relationship between the resource investment into male and female reproduction and the consequent fitness returns (often called fitness‐gain curves). Here we investigate the effects of resource availability on the sex allocation of a simultaneously hermaphroditic animal, the free‐living flatwormMacrostomum lignano. We kept the worms under different resource levels and determined the size of their testes and ovaries over a period of time. At higher resource levels, worms allocated relatively more into the female function, suggesting a saturating male fitness‐gain curve for this species. A large part of the observed effect was due to a correlated increase in body size, showing size‐dependent sex allocation inM. lignano. However, a significant part of the overall effect was independent of body size, and therefore likely due to the differences in resource availability. Moreover, in accordance with a saturating male fitness‐gain curve, the worms developed the male gonads first. As the group size was kept constant, our results contrast with expectations from sex allocation models that deal with local mate competition alone, and with previous experiments that test these models.
STOBADINE PROTECTS RAT KIDNEY AGAINST ISCHAEMIA/REPERFUSION INJURY
Authors: Guz Galip , Demirogullari Billur , Ulusu Nuray N , Dogu Cihangir , Demirtola Arzu , Kavutcu Mustafa , Omeroglu Suna , Stefek Milan , Karasu Cimen
Published: January 2007

Ischaemia–reperfusion (I/R) injury, one of the main causes of acute renal failure, still needs satisfactory treatment for routine clinical application. Stobadine, a novel synthetic pyridoindole anti‐oxidant, has the ability to reduce tissue injury induced by mechanisms involving reactive oxygen species during I/R. The aim of the present study was to determine the effects of stobadine on renal I/R injury.

Forty male Wistar rats were randomly divided into four groups as follows: sham, I/R, stobadine treated and I/R + stobadine treated. Stobadine (2 mg/kg, i.v.) was given intravenously to two groups of rats. The stobadine‐treated group was treated with stobadine following sham operation before the abdominal wall was closed, whereas the I/R + stobadine group received stobadine at the beginning of reperfusion. Renal I/R was achieved by occluding the renal arteries bilaterally for 40 min, followed by 6 h reperfusion. Immediately thereafter, blood was drawn and tissue samples were harvested to assess: (i) serum levels of blood urea nitrogen and creatinine; (ii) serum and/or tissue levels of malondialdehyde (MDA), glutathione (GSH), glucose 6‐phosphate dehydrogenase (G‐6PD), 6‐phosphogluconate dehydrogenase (6‐PGD), glutathione reductase (GR) and glutathione peroxidase (GPx); (iii) renal morphology; and (iv) immunohistochemical staining for P‐selectin.

Stobadine was able to significantly attenuate the renal dysfunction as a result of renal I/R injury. Iscahemia–reperfusion resulted in a significant increase in serum and kidney MDA levels and a decrease in serum and kidney GSH. Stobadine treatment at the beginning of reperfusion attenuated both the increased MDA levels and decreased GSH secondary to I/R injury. In addition, the decreased G‐6PD activity observed after I/R was significantly attenuated by stobadine treatment. Stobadine did not alter 6‐PGD activity after I/R. Neither GR nor GPx activity was significantly changed in the I/R alone or the I/R + stobadine groups compared with the sham group. In addition, stobadine decreased the morphological deterioration and high P‐selectin immunoreactivity secondary to renal I/R injury.

A pyridoindole anti‐oxidant, stobadine exerts a renal protective effect in renal I/R injury, which is probably due to its radical‐scavenging and anti‐oxidant activities.
AMELIORATIVE EFFECT OF CHLOROPHYTUM BORIVILIANUM ROOT ON LIPID METABOLISM IN HYPERLIPAEMIC RATS
Authors: Visavadiya NP , Narasimhacharya AVRL
Published: January 2007

The present study examined the efficacy of Chlorophytum borivilianum root (powder) in modulating the hyperlipaemic/hypercholesteraemic conditions in male albino rats.

Administration of C. borivilianum (0.75 and 1.5 g root powder/rat per day for 4 weeks) to hypercholesteraemic rats significantly increased high‐density lipoprotein–cholesterol levels and decreased plasma and hepatic lipid profiles.

In addition, there were significant increases in faecal cholesterol, neutral sterol and bile acid excretion with elevated hepatic 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase activity and bile acid production.

Furthermore, the hypercholesteraemic rats treated with both doses of C. borivilianum also exhibited increases in superoxide dismutase and ascorbic acid levels.

Normocholesteraemic animals treated with both doses of C. borivilianum root powder did not show any significant variation in either lipid or anti‐oxidant profiles, except for an increase in the hepatic ascorbic acid concentration compared with their untreated counterparts.

The hypolipaemic/hypocholesteraemic effect of C. borivilianum root powder appears to be mediated by an increase in cholesterol turnover via increased faecal cholesterol excretion and, second, through an endogenous cholesterol conversion into bile acid.

Administration of C. borivilianum root powder also increased the activities of anti‐oxidant enzymes and vitamin C levels, which may have enhanced the anti‐oxidant capacity of the liver.
NF2 gene expression in sporadic meningiomas: Relation to grades or histotypes real time‐PCR study
Authors: Buccoliero Anna M. , Castiglione Francesca , Degl’Innocenti Duccio R. , Gheri Chiara F. , Garbini Francesca , Taddei Antonio , Ammannati Franco , Mennonna Pasquale , Taddei Gian L.
Published: January 2007

One of the most common regions involved in the meningiomas tumorigenesis is chromosome 22q where the NF2 gene resides. The deficiency or loss of the NF2 gene product, merlin/schwannomin, plays a role in tumor development and metastatization. Conflicting results have been reported on the prognostic value of merlin in meningiomas. Several studies have indicated NF2 gene inactivation as an early tumorigenic event unrelated to the histological grade or clinical behavior. On the contrary, the NF2 gene alteration rate differs between the different histotypes. A pathogenesis independent from the NF2 gene has been suggested in meningothelial meningiomas. In the present work, we studied the NF2 gene expression through real time‐PCR (RT‐PCR) in 30 meningiomas. The average of the NF2 gene expression of all meningiomas was considered as reference value. The average of expression of WHO grade I and II meningiomas was higher than the average of all meningiomas, whereas that of WHO grade III meningiomas was lower. When we compared the NF2 gene expression in the different meningioma grades we did not note a significant difference (P = 0.698) despite the tendency to decrease from grade I to grade III. The average expression of meningothelial meningiomas was higher than the reference value, and that of non‐meningothelial meningiomas was lower. The difference in NF2 gene expression between meningothelial and non‐meningothelial meningiomas was statistically significant (P = 0.013). Our data supports the finding that alterations in NF2 gene alteration are histotype related but not grade related.
Gliosarcoma with chondroid and osseous differentiation
Authors: Schittenhelm Jens , Erdmann Torsten , Maennlin Stefan , Will Bernd E. , Beschorner Rudi , Bornemann Antje , Meyermann Richard , Mittelbronn Michel
Published: January 2007

We present the case of a 65‐year‐old woman with a short‐term history of cognitive decline and neuropsychiatric symptoms. Neuroradiological examinations revealed a large left temporo‐occipital cystic and calcified tumor mass measuring 6 cm in diameter, which was suspicious for an oligodendroglioma or a choroid plexus carcinoma. Neuropathological investigations finally revealed a gliosarcoma with extensive mesenchymal differentiation. The tumor demonstrated a biphasic pattern consisting of focal anaplastic glial components with vascular proliferation and necrosis. Adjacent sarcomatous tissue displayed pleomorphic fibroblastic cells surrounding metaplastic cartilage and osseous formation. Accounting for only approximately 2% of glioblastomas, gliosarcomas represent a rare entity of intrinsic CNS neoplasms. Exceedingly rare, the mesenchymal part of the gliosarcoma undergoes metaplastic transformation. Interestingly, in our case, the tumor exhibited features of both cartilaginous and osseous differentiation and multifocally showed a sharp transformation zone between highly malignant gliosarcomatous tumor areas and well‐differentiated non‐proliferative metaplastic regions.
A postsynaptic negative feedback mediated by coupling between AMPA receptors and Na+‐activated K+ channels in spinal cord neurones
Authors: Nanou Evanthia , El Manira Abdeljabbar
Published: January 2007

Na+‐activated K+ channels (KNa) exist in different types of neurones and their activation has been shown to depend on Na+ influx via voltage‐activated channels. However, one major route for Na+ influx into neurones is through ionotropic receptors and its role in activating KNa is still unclear. We have examined whether Na+ influx induced by activation of AMPA receptors can activate KNa in lamprey spinal cord neurones. Our results showed that the application of AMPA induced not only the characteristic inward current but also produced an outward current outlasting the activation of the receptors. This outward current was mediated by K+ and was abolished when Na+ was substituted with Li+. The AMPA‐mediated KNa current was completely blocked by quinidine but was not modulated by increased intracellular Cl– concentration or ATP. Thus, Na+ influx via AMPA receptor channels activates KNa with properties similar to Slack channels. The AMPA‐activated KNa may act as an inherent negative feedback mechanism to regulate the homeostasis of excitation.
Engineered expression of polysialic acid enhances Purkinje cell axonal regeneration in L1/GAP‐43 double transgenic mice
Authors: Zhang Yi , Zhang Xinyu , Yeh John , Richardson Peter , Bo Xuenong
Published: January 2007

Purkinje axons in adult mammals are generally unable to regenerate after axotomy. Our recent work has shown that over‐expression of growth related genes, GAP‐43 and L1, in Purkinje cells increased their axonal outgrowth into a predegenerated peripheral nerve graft, but not into a fresh graft [Zhang et al., (2005)Proc. Natl Acad. Sci. USA, 102, 14883–14888]. In the current study we investigated whether engineered expression of growth permissive molecule polysialic acid (PSA) in the glial scar or on transplanted Schwann cells could overcome the inhibitory environment and promote Purkinje axonal regeneration. A stab wound was introduced in the cerebellum of the L1/GAP‐43 transgenic mice and a lentiviral vector (LV) carrying the polysialyltransferase (PST) cDNA (LV/PST) was injected into the lesion site to transduce the cells in the glial scar. Regenerating Purkinje axons were examined by calbindin immunostaining. There was increased Purkinje axonal sprouting in the area expressing high‐level PSA. However, Purkinje axons were unable to grow into the lesion cavity. In the second set of experiments when LV/PST transduced Schwann cells were transplanted into the lesion site, the number of Purkinje axons growing into the transplant was nine times more than that growing into Schwann cell transplant expressing GFP two months post operation. Our result suggests that transplanted Schwann cells engineered to express PSA support axonal regeneration better than naïve Schwann cells.
Spinal anesthesia in neonates and infants – a single‐center experience of 505 cases
Authors: KACHKO LUDMYLA , SIMHI ELIAHU , TZEITLIN ELENA , EFRAT RACHEL , TARABIKIN EVELINA , PELED ELIA , METZNER IULIA , KATZ JACOB
Published: January 2007

Background:  Our aim was to assess the safety and efficacy of spinal anesthesia (SA) in newborns and infants undergoing surgery appropriate for this technique.

Methods:  The files of 505 patients who underwent surgery under spinal anesthesia since 1998 at a major tertiary hospital in Israel were analyzed retrospectively. SA was performed with bupivacaine 5 mg·ml−1 by attending pediatric anesthesiologists or an anesthesia resident. Demographic data, prematurity history, comorbidities, technical data, cardiovascular stability, complications and supplementary drugs were documented. The surgeon assessed the quality of anesthesia at the end of surgery.

Results:  Appropriate SA was achieved in 95.3% of cases; in 69.9% at the first attempt. The mean number of attempts per patient was 1.41 and mean dose of bupivacaine was 0.66 ± 0.16 mg·kg−1. Intravenous sedation, usually with midazolam (dose 0.1–0.2 mg·kg−1) was required in 28.1% of children because of crying/restlessness. Intraoperative conversion to general anesthesia was necessary in five patients (1.04%). The main side effect was bradycardia (<100 b·min−1) without desaturation which occurred in nine patients (1.8%). In three patients (0.62%), high spinal block occurred without bradycardia and hypotension. None of the patients had postoperative meningitis.

Conclusions:  SA is safe and effective in newborns and infants undergoing low abdominal, perineal and orthopedic surgery. In order to save time, our advice is to attempt SA after the surgeon is scrubbed, and minimize surgical teaching activity. The need to deal with a small and sometimes sick patient independent of the type of anesthesia requires the presence of an experienced pediatric anesthesiologist.
WHAT DO ECONOMISTS TELL US ABOUT VENTURE CAPITAL CONTRACTS?
Authors: Tykvová Tereza
Published: January 2007

Abstract Venture capital markets are characterized by multiple incentive problems and asymmetric information. Entrepreneurs and venture capitalists enter into contracts that influence their behaviour and mitigate the agency costs. In particular, they select an appropriate kind and structure of financing and specify the rights as well as the duties of both parties. The typical features of venture capital investments are an intensive screening and evaluation process, active involvement of venture capitalists in their portfolio companies, staging of capital infusions, use of special financing instruments such as convertible debt or convertible preferred stock, syndication among venture capitalists or limited investment horizon.
Volunteering and Income – The Fallacy of the Good Samaritan?
Authors: Hackl Franz , Halla Martin , Pruckner Gerald J.
Published: January 2007

This paper explores individual motives for volunteering. The analysis is based on the interpretation of volunteering as a consumption good (consumption model) or as a mean to increase individual's own human capital (investment model). We present an econometric framework taking into account self selection into volunteering and simultaneity between the volunteering decision and the determination of income in order to test these two models and to identify the underlying motives.

 We find strong statistical evidence for the investment model with a highly robust and significant impact of volunteering on the wage rate. Within the framework of the investment model it turns out that the number of volunteering hours plays a major role in explaining this wage premium. This supports the significance of skill acquisition to accumulate human capital, the importance of deepening of social contacts and signalling willingness to perform. As far as the consumption model is concerned we find no clear statistical evidence for its validity.
Finance and Firm Export in China
Authors: Du Jun , Girma Sourafel
Published: January 2007

Using a rich panel data set, we provide a rigorous analysis of the relationship between access to external finance, foreign direct investment and the exports of private enterprises in China. We conclude that, in order to foster the exports of indigenous enterprises, the elimination of financial discrimination against private firms is likely to be a more effective policy tool than the reliance on spillovers from multinational firms.
Using the 2001 Census to Study Human Capital Movements Affecting Britain's Larger Cities: Insights and Issues
Authors: Champion Tony , Coombes Mike
Published: January 2007

Human capital is increasingly being recognized as crucial to the sustained growth of British cities, and the population census is unrivalled as a source of data on the characteristics of people moving to and from cities. Taking advantage of new features in the 2001 census, the paper examines how successful 27 of Britain's largest cities and their regions are in maintaining their labour force complement, giving particular attention to young adults and people working in high level occupations. Considerable variation is apparent between city regions, but the interpretation of results is somewhat hampered by limitations in the census data, prompting recommendations for future data collection.
Fitting Disposition Codes to Mobile Phone Surveys: Experiences from Studies in Finland, Slovenia and the Usa
Authors: Callegaro Mario , Steeh Charlotte , Buskirk Trent D. , Vehovar Vasja , Kuusela Vesa , Piekarski Linda
Published: January 2007

Using mobile phones to conduct survey interviews has gathered momentum recently. However, using mobile telephones in surveys poses many new challenges. One important challenge involves properly classifying final case dispositions to understand response rates and non-response error and to implement responsive survey designs. Both purposes demand accurate assessments of the outcomes of individual call attempts. By looking at actual practices across three countries, we suggest how the disposition codes of the American Association for Public Opinion Research, which have been developed for telephone surveys, can be modified to fit mobile phones. Adding an international dimension to these standard definitions will improve survey methods by making systematic comparisons across different contexts possible.