bluuebunny/crossref_metadata_2025 huggingface dataset:
From forest to pasture: an evaluation of the influence of environment and biogeography on the structure of beetle (Scarabaeinae) assemblages along three altitudinal gradients in the Neotropical region
Authors: Escobar Federico , Halffter Gonzalo , Arellano Lucrecia
Published: November 2007

The objective of this study is to evaluate the effect of environmental (associated with the expansion of cattle ranching) and biogeographical factors on the diversity of dung beetle (Scarabaeinae) assemblages along three altitudinal gradients in the Neotropical region. One gradient is located in the Mexican Transition Zone, on the Cofre de Perote mountain, the other two are in the northern Andes (the Chiles Volcano and the Río Cusiana Basin). For the three gradients, the number of species and of individuals was similar in both forest and pasture, while species composition was different between habitats. On this mountain, species turnover in pastures was characterized by the addition of new species as altitude increased. In the northern Andes, species diversity was always greater in the forest than in the pasture, and species turnover between habitats was notably influenced by species loss with increasing altitude. As such the pasture fauna of the northern Andes was an impoverished derivative of the fauna present in the forests at the same altitude characterized by species of Neotropical affinity with a limited capacity for colonizing open, sunnier habitats. The opposite occurs in the areas used by cattle on the Cofre de Perote. This habitat has its own fauna, which is mainly comprised of Holarctic and Afrotropical species adapted to the prevailing environmental conditions of areas lacking arboreal vegetation. These results suggest that the impact on beetle communities caused by human activities can differ depending on the geographic position of each mountain and, particularly, the biogeographical history of the species assemblage that lives there.
Intraspecific facilitation: a missing process along increasing stress gradients – insights from simulated shrub populations
Authors: Malkinson Dan , Jeltsch Florian
Published: November 2007

In recent years many field studies have been conducted to assess the relative importance of facilitation and competition in structuring vegetation communities in different environments. Herein, we present a simulation model which systematically explores the relative importance of intra‐specific facilitation and competition between adult shrubs and seedlings for spatial pattern formation. A grid‐based simulation model was constructed and calibrated using data collected in the field from Sarcopoterium spinosum populations in Israel to simulate population dynamics along a rainfall gradient. A series of simulation experiments was conducted in which manipulations of seedling survival probabilities were carried out to assess the relative importance of these processes in generating spatial patterns. Increased survival probabilities of first‐year shrubs in open areas were used to simulate competition effects, while increased survival probabilities in the vicinity of shrubs were used to simulate facilitation effects.

Simulation results were then compared to shrub spatial patterns observed in the field. The results indicate that facilitation is not an important process in generating intra‐specific spatial patterns. Rather, in mesic environments with high precipitation, competition is the dominant process generating spatial patterns, resulting in regular spacing of shrubs, similarly to the patterns observed in the field (L(h) values<0). In arid sites, where precipitation values are lower, and stress conditions are higher, the dominant process generating spatial patterns was random mortality due to drought conditions. The resulting spatial patterns in this case are random (L(h)∼0), whereas observed field populations exhibited clumped patterns (L(h)>0). We conclude that as stress conditions increase, the importance of intraspecific neighborhood interactions decrease whereas the importance of environmental factors increase in dictating intra‐specific spatial pattern formation. Consequently in mesic environments intra‐specific competition among adults determines the emerging patterns, while intraspecific facilitation is a negligible process.
Covariation among demographic and climate parameters in whiskered auklets Aethia pygmaea
Authors: Jones Ian L. , Hunter Fiona M. , Robertson Gregory J. , Williams Jeffrey C. , Vernon Byrd G.
Published: November 2007

Annual survival rate and other demographic parameters of whiskered auklets Aethia pygmaea, a small planktivorous seabird, were measured at Buldir Island Alaska during 1992–2003 to provide comparative information for auk life history studies and to test for links among climate, age, productivity and survival. Using two 9 m mistnets, we captured and recaptured 384 adult and 193 sub‐adult (one year old, a known‐age component of our sample) birds as they arrived at the colony after dark during May and June (1,730 capture events). The best fitting model indicated a lower initial survival rate over the first year following marking (0.708±0.036 SE), and subsequent survival (mean 0.835±0.029) covarying with the Aleutian Low Pressure climate Index, with higher auklet survival in years with weak low pressure over the Aleutian Islands. Annual survival rate varied from 0.726±0.127 in 1998–99 to 0.994±0.077 in 1994–95, rates similar to those previously reported for least A. pusilla and crested auklets A. cristatella. A model based only on recaptures of known‐age birds indicated a lower local survival estimate over the first year following marking (age one to two years), with no other age‐effects on survival. Breeding propensity by age inferred from recaptures of birds with fully‐developed brood patches that were originally marked as sub‐adults (one year olds) indicated 53% breeding at age two, 94% breeding at age 3, 97% breeding at age 4 and 100% breeding thereafter. The sex ratio of the sampled birds was significantly male biased (60/40), likely due to differences in behaviour between males and females during the incubation stage. Taken together, our data indicate that whiskered auklet survival and productivity covaried with continuous variation in large‐scale climatic conditions, the mechanism being either negative effects of stormy North Pacific weather or indirect effects on food supplies.
Wing‐bone length allometry in birds
Authors: Nudds Robert L.
Published: November 2007

A comparative analysis using both independent contrasts (CAIC) and a species level analysis was used to investigate the allometric scaling of avian wing‐bone lengths. Total arm (ta=humerus+ulna+manus) scaled with positive allometry as body mass (M)0.37–0.39. Similarly, and in accordance with previous studies, wing‐span (b) was positively allometric, but CAIC suggested a lower allometric exponent (M0.35) than found using species as independent data points (M0.39). Contrary to previous studies, individual wing‐bones appear to scale with similar exponents againstMand scale isometrically withta. In addition to a general trend for larger birds to have longer wings, wing‐bones andta, theirtawas a larger proportion of theirb. A detailed study of primary feather length and elbow joint angle across a wide range of bird species and bird size, however, is required before a conclusive explanation for this increase intarelative tobin larger birds can be established. Scaling equations are presented that can be used to predictM,taandbfrom individual wing‐bone lengths, which may be of use to palaeontologists wishing to reconstruct whole animals from single bones.
Does the strength of an immune response reflect its energetic cost?
Authors: Nilsson Jan‐Åke , Granbom Martin , Råberg Lars
Published: November 2007

The energetic cost of immune responses has been proposed to be an important basis for trade‐offs between life‐history traits, such as between survival and reproduction. A critical assumption of this hypothesis is that the magnitude of the energetic cost increases with the strength of an immune response, so that energy can be saved by partly suppressing a response. Here, we test this assumption experimentally. The immune system of great titsParus majorwas experimentally activated by injecting different doses of phytohemagglutinin (PHA) in the wing web. We found the resting metabolic rate of immune challenged birds to increase by 5%. However, although great tits injected with a high dose had a stronger immune response, this was not paralleled by a higher metabolic rate. Thus, we found the energetic cost of the immune response to be relatively low and not dose‐dependent. This suggests to us that the energetic cost of immune responses cannot form the basis for trade‐offs between life‐history traits.
Effect of Japanese lesser sparrowhawks Accipiter gularis on the nest site selection of azure‐winged magpies Cyanopica cyana through their nest defending behavior
Authors: Ueta Mutsuyuki
Published: November 2007

The frequency of azure‐winged magpies Cyanopica cyana that nest in association with breeding Japanese lesser sparrowhawks Accipiter gularis was compared between the 1990s and 2000s. During 1990–1994 azure‐winged magpies nested within 50 m of their nests in all of the hawk nest sites studied. During 2005–2006, however, the magpies nested in only two of nine hawk nest sites. During the 1990s Japanese lesser sparrowhawks chased jungle crows away when they intruded within 50 m of their nest. During the 2000s, on the other hand, the hawks attempted to expel few crows at a distance of more than 10 m from their nest. As a result of it, the predation rate of simulated magpie nests located in the hawk nest sites was significantly higher during the 2000s. This suggests that the magpies have the ability to assess the defending behavior of the hawks and judge whether they can rely on their defense. Most azure‐winged magpies may stop nesting in association with breeding Japanese lesser sparrowhawks because of the reduced defending range of their nest sites.
A putative RNA‐binding protein has a role in virulence in Ralstonia solanacearum GMI1000
Authors: FRANKS ASHLEY , MARK‐BYRNE G. LOUISE , DOW J. MAXWELL , O’GARA FERGAL
Published: November 2007

Molecular signals contained in root exudates are thought to induce specific transcriptional changes in bacteria within the rhizosphere, promoting the expression of genes associated with rhizosphere function. We have previously used Pseudomonas aeruginosa PAO1 as a model organism to identify novel genes with roles in rhizosphere competitiveness through analysis of those which showed altered transcription in response to root exudates. One such gene, PA4753, encodes a putative RNA‐binding protein. Homologues of PA4753 occur in other rhizosphere‐associated bacteria, including the phytopathogen Ralstonia solanacearum. In this study, we have tested the role of this homologue, Rsc1524, in the virulence of R. solanacearum GMI1000. Disruption of Rsc1524 resulted in a decrease in virulence in tomato and Arabidopsis. This was associated with an increase in the level of specific extracellular plant wall‐degrading enzymes. Expression of Rsc1524 was influenced by different plant root exudates and root exudate components, which suggests that it may play a role in molecular signalling between bacteria and plants underpinning wilt pathogenesis.
A randomised, crossover comparison between the CobraPLA® and the LMA Classic™ in paralysed patients*
Authors: Nam S. B. , Han D. W. , Chang C. H. , Lee J. S.
Published: November 2007

We performed a randomised, crossover study in 38 anaesthetised and paralysed patients to compare the performance of the CobraPLA® and the LMA Classic™ during controlled ventilation. The median (IQR [range]) airway leak pressure was 23.0 (20–24 [12–30]) cmH2O for the CobraPLA and 15.0 (12–19 [8–30]) cmH2O for the LMA Classic (p < 0.001). The median (IQR [range]) insertion time was 15.0 (11–26 [9–31]) s for the CobraPLA and 22.5 (20–25 [15–50]) s for the LMA Classic (p < 0.001). There was no significant difference between the two devices for the number of insertion and reposition attempts, the anatomical position scored by fibreoptic bronchoscopy or the peak and plateau airway pressures. There were no adverse events during anaesthesia. The CobraPLA provides a better airway leak pressure and takes less time to insert than the LMA Classic in paralysed patients. Our data show that the CobraPLA can be used to secure a patent airway during controlled ventilation in selected patients.
Pulmonary function and inflammatory markers in patients undergoing coronary revascularisation with or without cardiopulmonary bypass
Authors: Heijmans J. H. , Liem K. S. A. E. , Damoiseaux G. M. C. , Maessen J. G. , Roekaerts P. M. H. J.
Published: November 2007

Lung injury after cardiac surgery is believed to result from cardiopulmonary bypass and its pro‐inflammatory effects. To test this hypothesis, we compared the oxygenation ratios, extravascular lung water indices and systemic and pulmonary tumour necrosis factor alpha (TNF‐α) and interleukin (IL)‐8 at predetermined intervals in coronary artery surgery patients with or without cardiopulmonary bypass. No differences in oxygenation ratios or extravascular lung water indices were found. Serum values of TNF‐α and IL‐8 increased in both groups but were higher in the cardiopulmonary bypass group (end of surgery: mean (SD) TNF‐α 3.68 (2.5) vs 2.20 (1.2) pg.ml−1 (p = 0.043 (CI 0.05–2.9)) and mean (SD) IL‐8 19.45 (10.8) vs 6.31 (5.3) pg.ml−1 (p = 0.001 (CI 6.9–19.3)). In broncho‐alveolar lavage fluid, TNF‐α and IL‐8 increased in both groups with no differences between the groups.
Contamination of anaesthetic machines with pathogenic organisms*
Authors: Baillie J. K. , Sultan P. , Graveling E. , Forrest C. , Lafong C.
Published: November 2007

Hospital‐acquired infections are commonly resistant to antibiotics and cause substantial morbidity and mortality in susceptible populations. Although there is no direct contact between the anaesthetic machine's controls and the patient, there is considerable potential for colonising organisms to be carried between the anaesthetic machine and the patient on the anaesthetist's hands. We performed two cross‐sectional studies of bacterial contamination on anaesthetic machines before and after a simple intervention. Without warning, during theatre sessions, bacterial cultures were obtained from anaesthetic equipment. A new departmental policy of cleaning anaesthetic equipment with detergent wipes between cases was then introduced. Six weeks later, again without warning, a further set of cultures was taken. There was significant reduction in the proportion of cultures containing pathogenic bacteria (from 14/78 cultures (18%; 95% CI 9.4–26.5%) before the intervention to 5/77 cultures (6%; 95% CI 1.0–12%) after the intervention (p = 0.03)). The intervention was quick, easy and enthusiastically taken up by the majority of staff. We conclude that cleaning of anaesthetic equipment between cases should become routine practice.
The role of liquid‐based cytology in the investigation of thyroid lesions
Authors: Stamataki M. , Anninos D. , Brountzos E. , Georgoulakis J. , Panayiotides J. , Christoni Z. , Peros G. , Karakitsos P.
Published: November 2007

Objective:  This study investigates the role of liquid‐based cytology by ThinPrep® technique in the detection of thyroid lesions.

Methods:  In all, 252 specimens from 157 patients for pre‐operative evaluation of thyroid nodules, prepared by the ThinPrep®, were examined. In all cases thyroidectomy followed the initial cytological evaluation. All cytological diagnoses were correlated to the histological ones.

Results:  According to our findings, a sensitivity of 87.80%, a specificity of 99.50%, a positive predictive value of 97.30%, a negative predictive value of 97.56% and an overall accuracy of 97.52% were observed in fine needle aspiration cytology in correlation to the histological diagnosis after thyroidectomy.

Conclusions:  ThinPrep® technique is a valid method for the pre‐operative cytological diagnosis of thyroid nodules, offering the possibility of ancillary techniques, such as immunocytochemical and molecular methods and can, therefore, be potentially complementary to histological evaluation for further investigation of follicular lesions.
Non‐enzymatic hydrolysis of fluorescein diacetate (FDA) in a Mediterranean oak (Quercus ilex L.) litter
Authors: Alarcón‐Gutiérrez E. , Floch C. , Ruaudel F. , Criquet S.
Published: November 2007

We show the presence of interfering substances when the total microbial activity in litter samples is measured with fluorescein diacetate (FDA), and we propose some methodological modifications to avoid such interference. Three distinct litter layers (the OhLn, the OhLv and the OhLf) of evergreen oak (Quercus ilex L.) were characterized by 13C CPMAS NMR and the spectra show that the recalcitrant aromatic and phenolic compounds increase with the degree of degradation of litter. A wide range of sources of interference in the hydrolysis of FDA was found. To understand the origin of this interference, sterilized litter materials (i.e. γ‐irradiated or autoclaved) and a wide range of organic substances (i.e. amino acids, glucose, sorbitol and organic humic acids) were investigated. Insignificant differences on the FDA hydrolysis activity (FDA activity) were found in the γ‐irradiated and non‐irradiated OhLn litter, indicating that γ‐irradiation does not destroy enzymes. Conversely, after heat‐sterilization of litter, samples showed FDA activity corresponding to 60, 34.8 and 30.8% (in the OhLn, the OhLv and the OhLf layers, respectively) of that of control litters. This indicates the presence of non‐enzymatic interfering substances in the FDA assays. As the humification and litter depth increased, hydrolysis of FDA due to interferences decreased, indicating degradation and/or chelation of interfering substances. We hypothesize that lysine, arginine, histidine and cysteine are mainly responsible for the hydrolysis of FDA. We suggest that the use of phosphate buffer (50 mm, pH 7.0) with incubation < 30 minutes, in combination with a temperature between 30 and 40°C, produces insignificant interference in the determination of the final FDA activity in litter samples.
Soil podzolization induced by reforestation as shown by sequential and kinetic extractions of Fe and Al
Authors: Cornu S. , Besnault A. , Bermond A.
Published: November 2007

The impact of 60‐year‐old reforestation on soil evolution was studied by following the evolution of Fe and Al distribution as an indicator of early podzolization. We determined the distribution of Al and Fe in soils by combining sequential and kinetic extractions. We extracted the soil sequentially with: 1 mol litre−1 sodium acetate at pH 5.5 (stage 1); twice with 0.1 mol litre−1 sodium pyrophosphate at pH 10 (stage 2 and 2b); and with 1 mol litre−1 hydroxylamine in 4.3 mol litre−1 acetic acid solution at 90°C (stage 3). For each, we drew a kinetic‐extraction curve. We show that no re‐adsorption, precipitation or complexation with dissolved organic matter occurred for the reaction times recommended in this procedure, that is 6 hours for stage 1, 1.5 hours for stage 2 and 2b and 3 hours for stage 3. For a given extraction, the kinetic curves have the same shape for all samples, that is their behaviour is similar for a given reagent. Sequential extraction can therefore be used to compare the speciation of metals in different samples taken from the same soil. In addition, 60 years after reforestation by beech, a decrease of 12 and 17% is noted in the total Fe and Al contents, respectively, in the 0–10 cm layer, accompanied by a re‐distribution of these elements within the different soil compartments: a decrease of the Fe and Al bound to oxy‐hydroxide in favour of organic complexes and more soluble forms. Sequential extraction is therefore a good indicator of the first pedogenetic modifications induced by human intervention through reforestation.
The impact of successive infections on the lung microenvironment
Authors: Didierlaurent Arnaud , Goulding John , Hussell Tracy
Published: November 2007

The effect of infection history on the immune response is ignored in most models of infectious disease and in preclinical vaccination studies. No one, however, is naïve and repeated microbial exposure, in particular during childhood, shapes the immune system to respond more efficiently later in life. Concurrent or sequential infections influence the immune response to secondary unrelated pathogens. The involvement of cross‐reactive acquired immunity, in particular T‐cell responses, is extensively documented. In this review, we discuss the impact of successive infections on the infected tissue itself, with a particular focus on the innate response of the respiratory tract, including a persistent alteration of (1) epithelial or macrophage expression of Toll‐like receptors or adherence molecules used by subsequent bacteria to invade the host, (2) the responsiveness of macrophages and neutrophils and (3) the local cytokine milieu that affects the activation of local antigen‐presenting cells and hence adaptive immunity to the next infection. We emphasize that such alterations not only occur during coinfection, but are maintained long after the initial pathogen is cleared. As innate responses are crucial to the fight against local pathogens but are also involved in the maintenance of the homeostasis of mucosal tissues, dysregulation of these responses by repeated infections is likely to have a major impact on the outcome of infectious or allergic disease.
Having your water and drinking it too: resource limitation modifies density regulation
Authors: BRADSHAW COREY J. A.
Published: November 2007

Determining the interaction between extrinsic and intrinsic drivers of variation in population abundance through time continues to challenge ecologists. Chamaillé‐Jammes and colleagues (this issue) examined African elephant time series to explore how water availability alters the density feedback mechanisms restricting population growth. The relationship between population growth rate and density shifted from an upward convex to a more linear form after controlling for rainfall. Spatial variation in water availability also attenuated density dependence as elephants adjusted their distribution relative to current environmental conditions. This work has important climate change implications for the conservation management of African herbivores.
Importance of sampling design and analysis in animal population studies: a comment on Sergio et al.
Authors: Kéry Marc , Royle J. Andrew , Schmid Hans
Published: November 2007

The use of predators as indicators and umbrellas in conservation has been criticized. In the Trentino region, Sergio et al. (2006; hereafter SEA) counted almost twice as many bird species in quadrats located in raptor territories than in controls. However, SEA detected astonishingly few species. We used contemporary Swiss Breeding Bird Survey data from an adjacent region and a novel statistical model that corrects for overlooked species to estimate the expected number of bird species per quadrat in that region.

There are two anomalies in SEA which render their results ambiguous. First, SEA detected on average only 6·8 species, whereas a value of 32 might be expected. Hence, they probably overlooked almost 80% of all species. Secondly, the precision of their mean species counts was greater in two‐thirds of cases than in the unlikely case that all quadrats harboured exactly the same number of equally detectable species. This suggests that they detected consistently only a biased, unrepresentative subset of species.

Conceptually, expected species counts are the product of true species number and species detectability p. Plenty of factors may affect p, including date, hour, observer, previous knowledge of a site and mobbing behaviour of passerines in the presence of predators. Such differences in p between raptor and control quadrats could have easily created the observed effects. Without a method that corrects for such biases, or without quantitative evidence that species detectability was indeed similar between raptor and control quadrats, the meaning of SEA's counts is hard to evaluate. Therefore, the evidence presented by SEA in favour of raptors as indicator species for enhanced levels of biodiversity remains inconclusive.

Synthesis and application. Ecologists should pay greater attention to sampling design and analysis in animal population estimation. Species richness estimation means sampling a community. Samples should be representative for the community studied and the sampling fraction among communities compared should be the same on average, otherwise formal estimation approaches must be applied to avoid misleading inference.
The influence of single molar crown placement on the smoothness of masticatory movement
Authors: WATAMOTO T. , MIZUMORI T. , EGUSA H. , YASHIRO K. , TAKADA K. , YATANI H.
Published: November 2007

Summary  The jerk‐cost is an index that can quantify the smoothness of various movements including human body movements. A previous study reported the usefulness of jerk‐cost in the evaluation of masticatory movement, and proposed that the masticatory movement of subjects with good occlusion could be explained as a maximum smooth movement. The purpose of this study was to investigate the influence of a single prosthetic molar restoration on the smoothness of masticatory movement. Fourteen adults who visited this hospital seeking a single prosthetic restoration on a molar were selected. Each subject chewed a piece of chewing gum on the molars of the treated side before and after crown placement. Movement trajectory was recorded using the Sirognathograph Analyzing System. Normalized jerk‐cost (NJC) was calculated on the closing phase of each chewing cycle and was compared before and after the crown placement. After the prosthetic restoration, NJC significantly decreased (P < 0·05) in seven subjects with a crown placed on a lower molar, whereas significant changes were not observed in seven subjects with a crown placed on an upper molar. These results suggest that restoring a crown on a lower molar could significantly improve the smoothness of masticatory movement on the same side.
Genome scans detect consistent divergent selection among subtidal vs. intertidal populations of the marine angiosperm Zostera marina
Authors: OETJEN KATHARINA , REUSCH THORSTEN B. H.
Published: November 2007

Genome scans are a powerful tool to detect natural selection in natural populations among a larger sample of marker loci. We used replicated habitat comparisons to search for consistent signals of selection among contrasting populations of the seagrass Zostera marina, a marine flowering plant with important ecological functions. We compared two different habitat types in the North Frisian Wadden Sea, either permanently submerged (subtidal) or subjected to aerial exposure (intertidal). In three independent population pairs, each consisting of one tidal creek and one tidal flat population each, we carried out a genome scan with 14 expressed sequence tag (EST)‐derived microsatellites situated in 5′‐ or 3′‐untranslated regions of putative genes, in addition to 11 anonymous genomic microsatellites. By using two approaches for outlier identification, one anonymous and two EST‐derived microsatellites showed population differentiation patterns not consistent with neutrality. These microsatellites were detected in several parallel population comparisons, suggesting that they are under diverging selection. One of these loci is linked to a putative nodulin gene, which is responsible for water channelling across cellular membranes, suggesting a functional link of the observed genetic divergence with habitat characteristics.
Accumulation of phosphorylated IκBα and activated IKK in nodes of Ranvier
Authors: Politi C. , Del Turco D. , Sie J. M. , Golinski P. A. , Tegeder I. , Deller T. , Schultz C.
Published: November 2007

Aims: Nuclear factor‐kappaB (NF‐κB) is an ubiquitously expressed transcription factor that modulates inducible gene transcription crucial for the regulation of immunity, inflammatory processes, and cell survival. In the mammalian nervous system, constitutive NF‐κB activation is considered to promote neuronal cell survival by preventing apoptosis. Increasing evidence suggests a critical role for NF‐κB activation in acute and chronic neurodegenerative diseases. Recently, a striking enrichment of phosphorylated IκBα (pIκBα) and activated IKappaB Kinase (IKK), two key components of the NF‐κB activation pathway, was demonstrated in the axon initial segment (AIS) of neurons. As the AIS shares fundamental features with nodes of Ranvier (NR), we examined whether pIκBα and activated IKK are also enriched in NR. Methods: Double‐immunofluorescence labelling was performed with vibratome sections of the rodent central and peripheral nervous system. Sections were analysed using confocal laser scanning microscopy and preembedding electron microscopy. Results: Here we report a remarkable accumulation of pIκBα and activated IKK in NR in the central and peripheral nervous system. Immunolabelling for both proteins extended from NR into the adjacent paranode. pIκBα predominantly accumulated within the cytoplasm and was associated with fasciculated microtubules. This association was confirmed by electron microscopy. By comparison, activated IKK preferentially clustered beneath the cytoplasmic membrane. Conclusion: In conclusion, the coincident accumulation of pIκBα and activated IKK in AIS and NR suggests that these specific axonal compartments contribute to neuronal NF‐κB activation.
Severe respiratory disorders in term neonates
Authors: Gouyon Jean‐Bernard , Ribakovsky C. , Ferdynus C. , Quantin C. , Sagot P. , Gouyon B. ,   Burgundy Perinatal Network
Published: November 2007

Few prospective population‐based studies of respiratory diseases have been conducted in term neonates. We aimed to describe mechanically ventilated respiratory disorders in term neonates and associated risk factors in a regional‐based study of livebirths between 37 and 41 weeks. The study was prospective for epidemiological data recording, and retrospective for collecting additional data from charts of neonates with severe (mechanically ventilated) respiratory disorders.

A total of 14 813 neonates with gestational age (GA) 37–38 weeks and 50 187 neonates with GA 39–41 weeks were included. The overall incidences (per thousand livebirths) of mechanically ventilated transient tachypnoea of the newborn (TTN) respiratory distress syndrome (RDS) and meconium aspiration syndrome (MAS) were 0.72‰[95% CI 0.53‰, 0.96‰], 0.38‰[95% CI 0.25‰, 0.57‰] and 0.61‰[95% CI 0.44‰, 0.84‰], respectively. Increasing GA from 37 to 41 weeks was associated with a significant decrease in incidence of RDS and TTN without any significant change for MAS.

Multivariable analysis was used to identify independent factors associated with severe respiratory disorders: in the 37–38 weeks group – Apgar score ≤3 at 1 min, elective caesarean section (CS), emergency CS and placental abruption; in the 39–41 weeks group – Apgar score ≤3 at 1 min, elective CS, emergency CS, meconium‐stained amniotic fluid and abnormal cardiotocography. Comparing the population attributable risks, the main risk factor of severe respiratory disorders was elective CS in the 37–38 weeks group and meconium‐stained amniotic fluid in the 39–41 weeks group.
A review of the ecology and management of Ranunculus acris subsp. acris in pasture
Authors: LAMOUREAUX S L , BOURDÔT G W
Published: November 2007

Ranunculus acris subsp. acris is widespread in pastures across Europe. In New Zealand, it persists in dairy pastures throughout the country, despite the annual use of herbicides, causing a loss in the national yield of milk solids estimated at NZ$156 million in the 2001–2002 milking season. Its persistence appears to be due in part to the production of a blistering agent, protoanemonin, which deters grazing animals, combined with evolved resistance to herbicides and a resilience imparted by a stout rhizome supporting dormant axillary buds. The latter enables regeneration after damage inflicted by herbicides, fungi and other control agents, and facilitates lateral spread and asexual reproduction. Its persistence in dairy pastures may also be influenced by plants recruiting from seeds which are formed annually subject to the availability of insect pollinators. Based on a review of observations and experiments conducted mainly in Europe and New Zealand, we propose a detailed life‐cycle model for R. acris. This provides the basis for a matrix population model that will identify the life‐cycle stages that contribute most to population growth and, hence, the extent to which each of these would need to be targeted for improved management in dairy pastures in New Zealand.
Genetic variation in transforming growth factor‐beta1 gene associated with increased risk of esophageal squamous cell carcinoma
Authors: Wei Y.‐S. , Xu Q.‐Q. , Wang C.‐F. , Pan Y. , Liang F. , Long X.‐K.
Published: November 2007

The genetic alterations leading to esophageal squamous cell carcinoma (ESCC) are gradually being discovered. A wide variety of genes have been associated with ESCC development as well as tumor progression. Transforming growth factor‐β1 (TGF‐β1) is a multifunctional cytokine; it promotes tumor growth and metastasis in later stages of of cancer development. Variations in the DNA sequence in the TGF‐β1 gene may lead to altered TGF‐β1 production and/or activity, and so this can modulate an individual’s susceptibility to ESCC. To test this hypothesis, we investigated the association of the TGF‐β1 gene −509 C/T and 869 T/C (Leu10Pro) polymorphisms and their haplotypes with the risk of ESCC. 247 patients with ESCC and 260 age‐ and sex‐matched controls were studied using a polymerase chain reaction–restriction fragment length polymorphism. There were significant differences in the genotype and allele distribution of 869 T/C polymorphism of the TGF‐β1 gene among cases and controls. The 869 TC and CC genotypes were associated with a significantly increased risk of ESCC as compared with the 869 TT genotypes [odds ratio (OR) = 1.882, 95% confidence interval (CI) 1.212–2.923, P = 0.005 and OR = 2.099, 95% CI 1.288–3.421, P = 0.003, respectively]. Consistent with the results of the genotyping analyses, the –509 T/869 C haplotype was associated with a significantly increased risk of ESCC as compared with the –509 C/869 T haplotype (OR = 1.463; 95% CI 1.120–1.912; P = 0.005). This study shows for the first time that TGF‐β1 gene 869 T/C polymorphism may contribute to a genetic risk factor for ESCC in a Chinese population.
Identified a novel allele HLA‐A*240212 by sequence‐based typing
Authors: Liu N. , Zhang Z.
Published: November 2007

A novel human leukocyte antigen‐A allele, A*240212, has been identified during routine sequence‐specific oligonucleotide typing and sequence‐based typing in a sample from a registered donor of Chinese Marrow Donor Program. The A*240212 allele differs from the most closely matching allele A*24020101 by one nucleotide substitution in Exon 2, at position 230, while the nucleotide exchange is silent mutation.
A novel HLA‐Cw*03 allele, Cw*033802, identified by sequence‐based typing
Authors: Kim M.‐H. , Oh H.‐B. , Kwon O.‐J.
Published: November 2007

New allele Cw*033802 showed one nucleotide difference with Cw*0338 at codon 99 (TAC→TAT).
Severe acute graft‐vs‐host disease in a patient with acute monocytic leukemia having a recombination event between HLA‐A/B loci from a multiple recombinant family
Authors: Sun Y. , Kong F. , Ren S. , Yuan F. , Liang F. , Liu N. , Jin L. , Xi Y.
Published: November 2007

Human leukocyte antigen (HLA) recombination, particularly multiple recombinations can produce novel haplotypes, thereby complicating donor–recipient selection and possibly inducing severe graft‐vs‐host disease (GVHD) after nonfully matched allogeneic hematopoietic stem cell transplantation. Here, we report for the first time that a 30‐year‐old female acute monocytic leukemia patient with an HLA‐A/B recombinant haplotype, who has three unmatched and one HLA‐B/DRB1 recombinant haplotype siblings, presented grade IV acute GVHD (aGVHD) after transplantation from a sibling with a single allele only mismatch at the classical HLA‐A locus. Furthermore, using a new three‐dimensional structure modeling application, we inferred that the structural differences in peptide‐binding and T‐cell receptor interaction sites can significantly change the immunogenicity of mismatched HLA molecules, potentially one of the main causes of aGVHD.
WZS‐pig is a potential donor alternative in corneal xenotransplantation
Authors: Zhiqiang Pan , Cun Sun , Ying Jie , Ningli Wang , Li Wang
Published: November 2007

Abstract:  Purpose:  To explore the characteristics of rejection of Wuzhishan (WZS) pig‐to‐rhesus monkey corneal transplants and to evaluate WZS pig corneas as potential donor material for a clinical setting.

Methods:  Wuzhishan pigs were used as donors and rhesus monkeys as recipients for corneal xenotransplantation. Eighteen rhesus monkeys were divided into three groups. Groups 1 and 2 underwent penetrating corneal xenotransplantation, while group 3 underwent lamellar corneal xenotransplantation. Only group 2 received subconjunctival injections with betamethasone for 3 months. All xenografts were evaluated by slit‐lamp microscopy. Two recipients in each group were killed for corneal histopathological staining at 30 days after surgery. The concentrations of cytokines in the aqueous humor were detected by cytometric bead array.

Results:  Rejection of the xenografts occurred at approximately 15 days after surgery in group 1. Rejection was delayed for more than 4 months by conjunctival injection with betamethasone (group 2). Use of lamellar corneal xenografts (group 3) maintained corneal transparency for more than 3 months. Histopathological examination in group 1 showed that the xenografts were infiltrated with inflammatory cells. The corneal endothelia were destroyed and exudative membranes were formed in the anterior chamber. However, in the betamethasone‐treated group, the corneal xenografts showed only minimal edema and almost no inflammatory cell infiltrate. The corneal endothelia were intact and there was no exudative membrane formation. The concentration of interleukin (IL)4, IL5 and IL10 showed an increased shift 3 weeks after surgery in group 1 and 2, but no change of cytokine’s concentration was found in group 3.

Conclusion:  Rejection of pig‐rhesus xenografts occurred early in penetrating corneal transplantation, but not in lamellar corneal transplantation. The endothelium of the xenograft might be a primary target of immune attack. Corticosteroid treatment inhibited rejection of the corneal xenografts.
Successful Induction of Antisera Against Rabbit Embryos for Isolation of the ICM and Putative Embryonic Stem Cells
Authors: Chiang S‐K , Chang H‐H , Ou Y‐W , Intawicha P , Cheng S‐P , Chen L‐R , Lee K‐H , Giles J , Ju J‐C
Published: November 2007

Contents

In Expt 1, goat antisera against rabbit blastocysts were induced using spleen cell injection and skin‐graft for immunosurgical isolation of ICM cells. Goats received rabbit spleen cell suspension (4 × 108 cells/ml) intravenously once a week for three consecutive weeks, plus an additional dose (boost injection) 10 days after the third injection, or a piece of rabbit skin (3 × 3 cm) transplantation. Blood samples were collected starting from the day after the last cell injection for 21 days. Serum was separated, heat inactivated and stored in frozen condition before titre analysis. Results showed that the antisera/antibodies derived by spleen cell injection reached their peak titre 7 days after the last cell injection, compared with 5 days by the skin‐grafted group. In Expt 2, morphologically normal blastocysts were collected for isolating ICMs immunosurgically or for direct culture of zona‐free whole blastocysts. In both methods, ICM cells started attaching to the feeder layer and outgrowing from the centre portion of the cells on day 3 after the onset of culture. ICM outgrowths increased in size during days 4–5, and most cells differentiated morphologically after day 6. One colony derived from isolated ICM developed into morphologically ES‐like cells expressing alkaline phosphatase activity. Our results indicated that both skin‐grafting and spleen cell injection were effective inducing antisera against rabbit embryonic cells. More studies are required to optimize the culture system for rabbit ES cells.
Blood Lymphocyte Subpopulations, Neutrophil Phagocytosis and Proteinogram During Late Pregnancy and Postpartum in Mares
Authors: Agrícola R , Carvalho H , Barbosa M , Pereira M , Medeiros JAS , Ferreira‐Dias G
Published: November 2007

Contents

The aim of this study was to evaluate peripheral blood lymphocyte subpopulations, neutrophil phagocytic capacity and proteinogram characteristics in mares, during the last trimester of pregnancy and in postpartum. Measurement of phagocytosis and quantification of T‐lymphocyte subsets were done by flow cytometry. Quantification of T‐lymphocyte subsets was performed with monoclonal antibodies specific for CD2, CD3, CD4 and CD8 cell markers. Natural killer and B‐cell counts were estimated mathematically. Serum proteinogram was obtained by electrophoresis. No significant differences were observed between gestation and postpartum on CD4+, CD8+ and NK+ lymphocyte subsets, CD4 : CD8 ratio and phagocytosis. The percentage of cells expressing CD3 (64.2 ± 1.8) and CD2 (68.4 ± 1.7) (Mean ± SEM) was reduced during gestation vs postpartum (69.7 ± 1.5 and 73.8 ± 1.4 respectively) (p < 0.05). During pregnancy, CD19+ (31.6 ± 1.7) was higher than in postpartum (26.2 ± 1.4) (p < 0.05). Total T cells (2911 ± 227 cells/μl), T helper cells (2144 ± 169 cells/μl) and T‐cytotoxic cells (767 ± 68 cells/μl) were depressed in pregnancy, when compared with postpartum (4093 ± 337 cells/μl; 3004 ± 276 cells/μl; 1089 ± 94 cells/μl respectively) (p < 0.01). Total white blood cell count was reduced during pregnancy (8815 ± 427 cells/μl) with respect to postpartum (10742 ± 446 cells/μl) (p < 0.01), while neutrophil count did not change. Total proteins, albumin, α1,α2,β1, β2, γ globulins and albumin : globulin did not differ. Our results suggest that the physiological immune depression occurring in mares, during gestation might be due to T‐helper and T‐cytotoxic lymphocytes reduction.
Evolution of pollinator generalization in bumblebee‐pollinated plants
Authors: SUZUKI KAZUO , DOHZONO IKUMI , HIEI KAYAKO
Published: November 2007

To understand the relationships between floral morphologies and the reproductive strategies of plants, the contributions of multiple pollinators to plant reproductive success need to be examined. To outline recent advances on this topic, we review studies of five bumblebee‐pollinated plants in Japan. These plant species are pollinated by one to three bumblebee species differing in proboscis length: Bombus consobrinus, Bombus diversus and Bombus honshuensis. These pollination systems allow us to compare the reproductive strategies of plants pollinated by single and multiple bumblebee species. First, we address the effects of morphological correspondence between flowers and pollinators on the reproductive success of plants. In plants with narrow tubular flowers, Isodon umbrosus and Clematis stans, pollination effectiveness depended on the morphological correspondence between floral tube length and pollinator mouthparts. These flowers are subject to varied directions and intensities of selection by multiple bumblebee species, resulting in the maintenance of large variation in floral morphology within and between populations, and even within individuals. In contrast, pollination effectiveness in plants having flowers with a wide entrance, Melampyrum roseum and Hosta sieboldiana, did not differ among bumblebee species because of good correspondence between floral morphology and bumblebee body size, resulting in small morphological variations among flowers. Thus, generalized pollination systems with multiple pollinator species favor floral traits that enable the use of various pollinators. Second, we address the quantity and quality of the pollination service in bumblebee‐pollinated plants. Isodon umbrosus, with its generalized pollination system, suffered from pollen limitation because of low pollination quality. In contrast, Isodon effusus, which has a specialized pollination system, suffered from pollen limitation because of low pollination quantity. Isodon umbrosus produced large numbers of short tubular flowers to improve pollination quantity, whereas I. effusus produced small numbers of long tubular flowers to improve pollination quality, resulting in a clear trade‐off between the size and number of flowers within plants. In M. roseum, which has a generalized pollination system, three bumblebee species achieved sufficient pollination, but seed production was limited by an increased rate of self‐pollination. This is because this species invests more resources in cross‐pollinated seeds by selective abortion of selfed seeds. Our results demonstrate that the strategy of generalized plants is to improve pollination quantity, whereas the strategy of specialized plants is to improve pollination quality.
Flower orientation on slopes in the myco‐heterotrophic species Monotropastrum globosum
Authors: IMAMURA AKIO , USHIMARU ATUSHI
Published: November 2007

We investigated the factors that determine the flower orientation of Monotropastrum globosum on a slope, and their effects on reproductive success. A previous study revealed that flowers on a slope faced the open space, which was presumed to increase pollinator attraction, and that orientation affected the reproductive success of individual flowers. When a plant has many inflorescences, interference among flowers may occur. We conducted a shading experiment to examine whether flower orientation changes in response to light conditions based on the angular distance between the slope and the flower direction (ADSF), and we analyzed the correlations between the position of individual flowers within plants, flower angle and ADSF, and the relationships between pollination and fruiting success and flower orientation. The shading experiment revealed that the flower orientation of M. globosum was affected by light, slope angle and flower position within a plant. The ADSF of the front flowers was smaller than that of the back flowers. However, flower orientation did not significantly affect either pollination or fruiting success, although the petal size of each flower did affect reproductive success. In M. globosum with multi‐inflorescences, individual flowers may face the open space to reduce interference among flowers within an individual.