bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of Ganoderma triterpenes with doxorubicin and proteomic characterization of the possible molecular targets of Ganoderma triterpenes
Authors: Yue Qing‐Xi , Xie Fu‐Bo , Guan Shu‐Hong , Ma Chao , Yang Min , Jiang Bao‐Hong , Liu Xuan , Guo De‐An
Published: April 2008

Triterpenes are the main components with cytotoxicity in Ganoderma lucidum, which is used popularly as a complementary treatment for cancer therapy in traditional Chinese medicine. To investigate the possible interaction between chemotherapeutic agents and triterpenes extracted from G. lucidum, the cytotoxicity of doxorubicin (DOX) combined with Ganoderma triterpenes (GTS) or lucidenic acid N (LCN), a purified compound, was examined in HeLa cells. The combinations targeting DOX with GTS or LCN resulted in a synergistic interaction in HeLa cells. Moreover, to identify the molecular targets of GTS, two‐dimensional gel electrophoresis‐based comparative proteomics was carried out and proteins with altered expression levels after GTS treatment in HeLa cells were identified by matrix‐assisted laser desorption/ionization time‐of‐flight tandem mass spectrometry. The results of our proteomic study indicated that the GTS treatment caused regulated expression of 14 proteins, which play important roles in cell proliferation, the cell cycle, apoptosis, and oxidative stress. Flow cytometric analysis confirmed that GTS could induce weak G0–G1 phase arrest and combined use of GTS with DOX could induce apoptosis in cells. Furthermore, GTS enhanced the reactive oxygen species (ROS)‐producing effect of DOX, and a ROS scavenger could affect the synergism between GTS and DOX. In cells with high Ku80 protein expression, the synergism between GTS and DOX was also partly affected. Importantly, in cells with high Ku80 expression that were treated with a ROS scavenger, the synergism between GTS and DOX totally disappeared. These results suggest that the synergism between GTS and DOX might be based on GTS‐induced sensitization of cells to chemotherapeutics through enhanced oxidative stress, DNA damage, and apoptosis. (Cancer Sci 2008; 99: 1461–1470)
Long‐term effects of heroin‐assisted treatment in Germany
Authors: Verthein Uwe , Bonorden‐Kleij Karin , Degkwitz Peter , Dilg Christoph , Köhler Wilfried K. , Passie Torsten , Soyka Michael , Tanger Sabine , Vogel Mario , Haasen Christian
Published: April 2008

Aims  Trials in Switzerland, the Netherlands and Spain have found that heroin‐assisted treatment (HAT) as maintenance treatment for opioid‐dependent patients reduces illicit drug use. A German trial also found diamorphine treatment to be superior to methadone treatment. The present study describes the association between 2 years of heroin treatment and improvements in health and social stabilization, as well as illicit drug use.

Design  A prospective cohort study design.

Participants  A total of 515 patients were assigned to diamorphine treatment; 278 patients remained in the study treatment for the entire period of 24 months (54.8%).

Measurements  The results on physical (Opiate Treatment Index Health Symptoms Scale) and mental (Symptom Checklist 90–Revised Global Severity Index) health and illicit drug use (number of days with drug use within the last month—European Addiction Severity Index) were examined by repeated‐measures analyses.

Findings  Symptoms of physical (Pillai's trace = 0.837, df = 4, P < 0.001) and mental health (Pillai's trace = 0.450, df = 4, P < 0.001) improved during treatment. Street heroin use declined rapidly (Pillai's trace = 0.836, df = 4, P < 0.001), as did cocaine use (Pillai's trace = 0.280, df = 4, P < 0.001).

Conclusions  HAT is associated with improvements in mental and physical health in the long term.
Critical issues in the treatment of hepatitis C virus infection in methadone maintenance patients
Authors: Novick David M. , Kreek Mary Jeanne
Published: April 2008

Aims Hepatitis C virus (HCV) infection is a common chronic complication of injection drug use. Methadone maintenance programs contain large numbers of patients infected with HCV. This paper reviews HCV infection with emphasis on the medical care of HCV‐infected, or HCV and human immunodeficiency virus co‐infected, patients on methadone or buprenorphine maintenance.

Methods Literature searches using PubMed, PsycINFO and SocINDEX were used to identify papers from 1990–present on antiviral therapy for HCV in methadone maintenance patients and on liver transplantation in methadone maintenance patients.

Results Injection drug use is the most significant risk factor for HCV infection in most western countries. The prevalence of HCV antibody is high in injection drug users (53–96%) and in patients enrolled in methadone maintenance programs (67–96%). Studies of antiviral therapy for HCV in methadone maintenance patients show rates of sustained virological response (SVR), defined as negative HCV‐RNA 24 weeks after the end of treatment, of 28–94%. In studies with contrast groups, no significant differences in SVR between methadone and contrast groups were found. Excellent completion rates of antiviral therapy (72–100%) were found in five of six studies. There are many barriers to methadone maintenance patients' receiving antiviral therapy, and research on overcoming barriers is discussed. Liver transplantation has been successful in methadone maintenance patients but has not been utilized widely.

Conclusion High quality medical care for all aspects of HCV infection can be provided to methadone maintenance patients. The literature supports the effectiveness of such services, but the reality is that most patients do not receive them.
Alcohol measurement methodology in epidemiology: recent advances and opportunities
Authors: Greenfield Thomas K. , Kerr William C.
Published: April 2008

Aim  To review and discuss measurement issues in survey assessment of alcohol consumption for epidemiological studies.

Methods  The following areas are considered: implications of cognitive studies of question answering such as self‐referenced schemata of drinking, reference period and retrospective recall, as well as the assets and liabilities of types of current (e.g. food frequency, quantity–frequency, graduated frequencies and heavy drinking indicators) and life‐time drinking measures. Finally we consider units of measurement and improving measurement by detailing the ethanol content of drinks in natural settings.

Results and conclusions  Cognitive studies suggest inherent limitations in the measurement enterprise, yet diary studies show promise of broadly validating methods that assess a range of drinking amounts per occasion; improvements in survey measures of drinking in the life course are indicated; attending in detail to on‐ and off‐premise drink pour sizes and ethanol concentrations of various beverages shows promise of narrowing the coverage gap plaguing survey alcohol measurement.
Genes associated with the tumour microenvironment are differentially expressed in curedversusprimary chemotherapy‐refractory diffuse large B‐cell lymphoma
Authors: Linderoth Johan , Edén Patrik , Ehinger Mats , Valcich Jeanette , Jerkeman Mats , Bendahl Pär‐Ola , Berglund Mattias , Enblad Gunilla , Erlanson Martin , Roos Göran , Cavallin‐Ståhl Eva
Published: April 2008

In order to identify genes associated with primary chemotherapy‐resistance, gene expression profiles (GEP) in tumour tissue from 37 patients with de novo diffuse large B‐cell lymphoma (DLBCL), stage II–IV, either in continuous complete remission (n = 24) or with progressive disease during primary treatment (n = 13), were examined using spotted 55K oligonucleotide arrays. Immunohistochemistry was used for confirmation at the protein level. The top 86 genes that best discriminated between the two cohorts were chosen for further analysis. Only seven of 86 genes were overexpressed in the refractory cohort, e.g.RABGGTBandPOLE, both potential targets for drug intervention. Seventy‐nine of 86 genes were overexpressed in the cured cohort and mainly coded for proteins expressed in the tumour microenvironment, many of them involved in proteolytic activity and remodelling of extra cellular matrix. Furthermore, major histocompatibility complex class I molecules,CD3DandICAM1were overexpressed, indicating an enhanced immunological reaction. Immunohistochemistry confirmed the GEP results. The frequency of tumour infiltrating lymphocytes, macrophages, and reactive cells expressing ICAM‐1, lysozyme, cathepsin D, urokinase plasminogen activator receptor, signal transducer and activator of transcription 1, and galectin‐3 was higher in the cured cohort. These findings indicate that a reactive microenvironment has an impact on the outcome of chemotherapy in DLBCL.
Induction of gamma‐globin gene transcription by hydroxycarbamide in primary erythroid cell cultures from Lepore patients
Authors: Calzolari Roberta , Pecoraro Alice , Borruso Vito , Troia Antonio , Acuto Santina , Maggio Aurelio , Di Marzo Rosalba
Published: April 2008

Increased expression of fetal haemoglobin (HbF) may ameliorate the clinical course of beta‐thalassemia and sickle cell disease. Some pharmacological agents, such as hydroxycarbamide (HC), can increase fetal haemoglobin synthesis during adult life. Cellular selection and/or molecular mechanisms have been proposed to account for this increase. To explore the mechanism of action of HC we focused on homozygous Hb‐Lepore patients that presented with high fetal haemoglobin levels and were good responders to HC treatment “in vivo”. We performed primary erythroid cultures from peripheral blood of four homozygous Lepore patients. The increase in HBG (γ‐globin) transcription levels and HbF content in these cultures, after HC treatment, were detected by quantitative real time polymerase chain reaction analysis and flow cytometric analysis. Primary transcript “in‐situ” hybridization analysis showed a 2‐fold increase in the number of cells expressing both HBG alleles in HC‐treated erythroid cultures. These studies, demonstrating the larger number of biallelic HBG expressing cells, suggest that HC is able to stimulate the activation of HBG transcription. These observations provide evidences that the molecular mechanism of action is involved in the increase of fetal haemoglobin production by HC.
Hypoxia inducible factor‐alpha activation in lymphoma and relationship to the thioredoxin family
Authors: Evens Andrew M. , Schumacker Paul T. , Helenowski Irene B. , Singh Amareshwar T. K. , Dokic Danijela , Keswani Anjeni , Kordeluk Elizabeth , Raji Adekunle , Winter Jane N. , Jovanovic Borko D. , Holmgren Arne , Nelson Beverly P. , Gordon Leo I.
Published: April 2008

Hypoxia inducible factors (HIFs) activate oncogenic pathways, while thioredoxins (Trx), including Trx1 and Trx reductases‐1 and ‐2 (TrxR1 and TrxR2), promote HIF‐α stabilization. In immunoblotting studies in lymphoma cell lines we found that Raji and SUDHL4 cells exhibited normoxic HIF‐2α protein stabilization. Five cell lines showed increased TrxR1 expression, while only Namalwa, HF1 and SUDHL4 had Trx1 and TrxR2 activation. Tissue microarrays in diffuse large B‐cell lymphoma (DLBCL) and follicular lymphoma (FL) identified different HIF expression among histological subgroups (e.g. 44% DLBCL vs. 11% of FL cases with moderate‐to‐high expression of HIF‐1α and HIF‐2α, P = 0·0017). These data demonstrate that HIF and the thioredoxin family are abnormally activated in lymphoma.
Sporadic bloody diarrhoea‐associated thrombotic thrombocytopenic purpura‐haemolytic uraemic syndrome: an adult and paediatric comparison
Authors: Karpac Charity A. , Li Xiaoning , Terrell Deirdra R. , Kremer Hovinga Johanna A. , Lämmle Bernhard , Vesely Sara K. , George James N.
Published: April 2008

Although diarrhoea‐associated haemolytic uremic syndrome (HUS) in children is well described, the clinical features of bloody diarrhoea‐associated thrombotic thrombocytopenic purpura (TTP)‐HUS in adults are not documented. Twenty‐one adults, 6·5% of the 322 adults in The Oklahoma TTP–HUS Registry, 1989–2006, have presented with bloody diarrhoea. There were no case clusters. Escherichia coli O157:H7 was identified in five patients, but many patients did not have appropriate studies. The annual incidence was 0·68/106, 10‐fold less than the incidence of diarrhoea‐associated HUS in children in Oklahoma. Two (13%) of 16 patients in whom ADAMTS13 (A Disintegrin And Metalloproteinase with a ThromboSpondin type 1 motif, member 13) was measured had <10% activity. Severe neurological abnormalities (67%) and renal failure (62%) were common; seven patients (33%) died; no survivors have relapsed. Compared to the 38 other Oklahoma Registry patients with ADAMTS13 <10%, frequency of severe neurological abnormalities and death was not different; frequency of renal failure was greater; frequency of relapse was less. Compared to 5999 children with sporadic diarrhoea‐associated HUS in published reports, frequency of renal failure and relapse was not different; frequency of severe neurological abnormalities and death was greater (P < 0·05 for all differences). Awareness of the continuous occurrence of sporadic bloody diarrhoea‐associated TTP–HUS in adults is important for prompt diagnosis and appropriate management.
Serum levels of adipocyte fatty acid‐binding protein (AFABP) are increased in chronic haemodialysis (CD)
Authors: Sommer Grit , Ziegelmeier Michaela , Bachmann Anette , Kralisch Susan , Lossner Ulrike , Kratzsch Jürgen , Blüher Matthias , Stumvoll Michael , Fasshauer Mathias
Published: April 2008

Objective  Adipocyte fatty acid‐binding protein (AFABP) was recently introduced as an adipocyte‐expressed factor, serum levels of which independently correlate with the development of the metabolic syndrome and cardiovascular disease in humans. In the current study, we investigated renal elimination of this protein by comparing circulating AFABP levels in patients on chronic haemodialysis (CD) with controls. We hypothesized that if renal filtration is a significant route of elimination of AFABP, it would accumulate in CD patients.

Patients and measurements  AFABP was determined by ELISA in control (n = 60) and CD (n = 60) patients and correlated to clinical and biochemical measures of renal function, glucose and lipid metabolism, as well as inflammation, in both groups.

Results  Median serum AFABP levels were more than 10‐fold higher in CD patients (510·9 ± 294·7 µg/l) as compared to controls (44·3 ± 35·2 µg/l). Furthermore, CD independently predicted AFABP concentrations in multiple regression analysis. In addition, body mass index and free fatty acids were independently associated with circulating AFABP.

Conclusions  Renal filtration appears as an important route of elimination of AFABP. Future studies should elucidate whether this adipocyte‐expressed factor contributes to the increased risk of cardiovascular disease found in end‐stage renal disease.
Genetic structure and demographic history of brown trout (Salmo trutta) populations from the southern Balkans
Authors: APOSTOLIDIS APOSTOLOS P. , MADEIRA MARIA‐JOSE , HANSEN MICHAEL M. , MACHORDOM ANNIE
Published: April 2008

1. The present study was designed to characterize the genetic structure of brown trout (Salmo trutta) populations from the southern Balkans and to assess the spread of non‐native strains and their introgression into native trout gene pools. We analysed polymorphism at nine microsatellite loci in seven supposedly non‐admixed and three stocked brown trout populations.

2. The analyses confirmed the absence of immigration and extraordinarily strong genetic differentiation among the seven non‐introgressed populations in parallel with low levels of intrapopulation genetic variability. In contrast, analyses of the stocked populations revealed that the genetic integrity of the local populations had been substantially changed, and the populations must be characterized as hybrid swarms. The pattern of population differentiation observed at microsatellites contrasted to that depicted previously by mtDNA variation. However, the close relationships between populations from the Danube and Axios river systems proposed solely by microsatellites could be explained by palaeogeographic events.

3. Our research showed that most of the populations examined represent unique gene pools, whose existence is critically compromised. Therefore, appropriate management and conservation strategies should be developed urgently in order to protect the subspecific biodiversity and to reverse currently negative trends.
Non‐lethal effects of invertebrate predators on Daphnia: morphological and life‐history consequences of water mite kairomone
Authors: CARTER MAURICIO J. , VEGA‐RETTER CAREN , RAMOS‐JILIBERTO RODRIGO
Published: April 2008

1. Here, we report morphological and life‐historical changes in the cladoceran Daphnia ambigua in response to chemical cues released by the predatory water mite Piona chilensis. Both species are common inhabitants of southern temperate lakes.

2. We found significant differences in adult body size at first, second and third reproduction. Also, individuals exposed to kairomones had longer tail spines at first reproduction, and the resultant offspring had smaller bodies and shorter tail spines.

3. Exposure to mite cues did not exert effects on brood size at first reproduction, but decreased offspring number in subsequent broods. Similarly, only the second and third reproduction events were delayed by kairomone exposure.

4. The intrinsic population growth rate of predator‐induced animals was lower than that in controls, but simulations based on a parameterized matrix model showed that the fitness costs could be overcome if the reported phenotypic responses reduced predation rate moderately. The gain in protection from predators needed to cancel out the reduction in fitness associated with predator cues was directly related to juvenile survival and fertility, and inversely related to adult survival.

5. This is the first work reporting phenotypic plasticity in Cladocera in response to kairomones released by water mites, which are conspicuous predators in many austral fresh waters.
Critically classifying: UK e‐government website benchmarking and the recasting of the citizen as customer
Authors: Mosse Benjamin , Whitley Edgar A.
Published: April 2008

In recent years, discussion of the provision of government services has paid particular attention to notions of customer choice and improved service delivery. However, there appears to be marked shift in the relationship between the citizen and the state moving from government being responsive to the needs of citizens to viewing citizens explicitly as customers. This paper argues that this change is being accelerated by government use of techniques like benchmarking, which have been widely used in the private sector. To illustrate this point, the paper focuses on the adoption of website benchmarking techniques by the public sector. The paper argues that the essence of these benchmarking technologies, a process comprised of both finding and producing truth, is fundamentally based on the act of classifying and draws on Martin Heidegger's etymological enquiry to reinterpret classification as a dynamic movement towards order that both creates and obfuscates truth. In so doing, it demonstrates how Heidegger's seminal ideas can be adapted for critical social research by showing that technology is more than an instrument as it has epistemic implications for what counts as truth. This stance is used as the basis for understanding empirical work reporting on a UK government website benchmarking project. Our analysis identifies the means involved in producing the classifications inherent in such benchmarking projects and relates these to the more general move that is recasting the relationship between the citizen and the state, and increasingly blurring the boundaries between the state and the private sector. Recent developments in other attempts by the UK government to use private‐sector technologies and approaches indicate ways in which this move might be challenged.
Relationship‐based e‐commerce: theory and evidence from China
Authors: Martinsons Maris G.
Published: April 2008

Abstract.  Electronic commerce models and prescriptions from rule‐based market economies like the United States have limited applicability in emerging markets. This paper adopts a strategic management perspective to examine the distinctive challenges facing e‐commerce in China. A theory is developed to explain how the lack of dependable rules encourages guanxi and relationship‐based commerce. It suggests that personal trust, contextual and informal information, and blurred boundaries between business and government have shaped e‐commerce in mainland China. Case studies of online retailers in Beijing and Shanghai and a business‐to‐business (B2B) marketspace reveal how dynamic business relationships with complementary service providers and state agents can overcome institutional deficiencies. Short message service (SMS)‐based mobile commerce (m‐commerce) and other leapfrogging information technology (IT) applications could transform Chinese consumer behaviour and improve economic efficiency. The evidence from China helps to explain the influence of culture and institutions on different types of IT applications. Implications for e‐commerce research and practice in China and other emerging markets are discussed.
The process of enterprise resource planning implementation and business process re‐engineering: tales from two Chinese small and medium‐sized enterprises
Authors: Newman Mike , Zhao Yu
Published: April 2008

Abstract.  Using an innovative process model, we describe and analyse the process of introducing enterprise resource planning (ERP) systems in two Chinese small and medium‐sized enterprises and especially their decisions concerning business process re‐engineering. First we compared the results from our cases with Martinsons' earlier work (2004). One case seemed to fit most of the characteristics of a private venture (PV) whereas the other case, also a PV, had a very low degree of fit. We used the process model to offer further insights and features such as its predictive power. Second, and as predicted, we also observed the differential role of top management support in the two Chinese companies. But thirdly, and somewhat surprisingly, we found that cultural issues were only of limited importance. Finally, the ability of the project team to deal with unexpected events was seen as critical in ensuring the stability of a project. In contrast, project drift is shown to lead to a degree of chaos. We offer some suggestions as to how stakeholders can improve their chances of implementing ERP systems more successfully.
Antifungal activity of fatty acids and their monoglycerides against Fusarium spp. in a laboratory medium
Authors: Altieri Clelia , Bevilacqua Antonio , Cardillo Daniela , Sinigaglia Milena
Published: April 2008

The antifungal activity of lauric, myristic and palmitic acids and their monoglycerides against fusaria was investigated. Data were modelled through a re‐parameterized Gompertz equation and the Minimum Detection Time (MDT), i.e. the time (days) to attain 1 cm colony diameter, was evaluated. Lauric acid exerted a strong bioactivity against moulds; palmitic and myristic acids and their monoglycerides showed a moderate effectiveness and in a reversible manner. The results of this work could be considered quite promising; however, further investigations are proposed to validate these data in foods.
The role of volatile compounds on aroma and flavour perception in coloured raw carrot genotypes
Authors: Kreutzmann Stine , Thybo Anette K. , Edelenbos Merete , Christensen Lars P.
Published: April 2008

Quantitative analyses of volatile compounds isolated from raw carrots were combined with sensory analysis in order to identify the role of these compounds on aroma and flavour perception in coloured carrots. A sensory map of carrots with different colours was developed, the content of the isolated volatiles was determined and the role of these compounds for harsh flavour perception in raw coloured carrots was evaluated using multivariate data analysis. The sensory map showed that the coloured carrots formed distinct groups within the sensory profile. The orange genotypes were characterised by having significantly higher intensities in carrot flavour and aroma, while the reverse was true for the yellow genotypes. The purple genotype was characterised by having significantly higher intensity in sickenly sweet flavour and nutty flavour, and the red genotype was characterised by having significantly higher intensities in green aroma and flavour, bitterness and burning aftertaste. From the multivariate data analysis it was concluded that the isolated terpenes do correlate to the harsh flavour attributes.
Tree species range shifts at a continental scale: new predictive insights from a process‐based model
Authors: Morin Xavier , Viner David , Chuine Isabelle
Published: April 2008

Climate change has already caused distribution shifts in many species, and climate predictions strongly suggest that these will accelerate in the future. Obtaining reliable predictions of species range shifts under climate change is thus currently one of the most crucial challenges for both ecologists and stakeholders.

Here we simulate the distributions of 16 North American tree species at a continental scale for the 21st century according to two IPCC storylines, using a process‐based species distribution model that for the first time allows identification of the possible causes of distribution change.

Our projections show local extinctions in the south of species ranges (21% of the present distribution, on average), and colonizations of new habitats in the north, though these are limited by dispersal ability for most species. Areas undergoing local extinctions are slightly larger under climate scenario A2 (+3.2 C, +22% on average) than B2 (+1.0 C, +19% on average). This small difference is caused by nonlinear responses of processes (leaves and flowers phenological processes in particular) to temperature. We also show that local extinction may proceed at a slower rate than forecasted so far.

Although predicted distribution shifts are very species‐specific, we show that the loss of habitats southward will be mostly due to increased drought mortality and decreased reproductive success, while northward colonizations will be primarily promoted by increased probability of fruit ripening and flower frost survival.

Synthesis. Our results show that different species will not face the same risks due to climate change, because their responses to climate differ as well as their dispersal rate. Focusing on processes, our study therefore tempers the alarming conclusions of widely used niche‐based models about biodiversity loss, mainly because our predictions take into account the local adaptation and trait plasticity to climate of the species.
Rainfall effects on rare annual plants
Authors: Levine Jonathan M. , McEachern A. Kathryn , Cowan Clark
Published: April 2008

Variation in climate is predicted to increase over much of the planet this century. Forecasting species persistence with climate change thus requires understanding of how populations respond to climate variability, and the mechanisms underlying this response. Variable rainfall is well known to drive fluctuations in annual plant populations, yet the degree to which population response is driven by between‐year variation in germination cueing, water limitation or competitive suppression is poorly understood.

We used demographic monitoring and population models to examine how three seed banking, rare annual plants of the California Channel Islands respond to natural variation in precipitation and their competitive environments. Island plants are particularly threatened by climate change because their current ranges are unlikely to overlap regions that are climatically favourable in the future.

Species showed 9 to 100‐fold between‐year variation in plant density over the 5–12 years of censusing, including a severe drought and a wet El Niño year. During the drought, population sizes were low for all species. However, even in non‐drought years, population sizes and per capita growth rates showed considerable temporal variation, variation that was uncorrelated with total rainfall. These population fluctuations were instead correlated with the temperature after the first major storm event of the season, a germination cue for annual plants.

Temporal variation in the density of the focal species was uncorrelated with the total vegetative cover in the surrounding community, suggesting that variation in competitive environments does not strongly determine population fluctuations. At the same time, the uncorrelated responses of the focal species and their competitors to environmental variation may favour persistence via the storage effect.

Population growth rate analyses suggested differential endangerment of the focal annuals. Elasticity analyses and life table response experiments indicated that variation in germination has the same potential as the seeds produced per germinant to drive variation in population growth rates, but only the former was clearly related to rainfall.

Synthesis. Our work suggests that future changes in the timing and temperatures associated with the first major rains, acting through germination, may more strongly affect population persistence than changes in season‐long rainfall.
Rhizobial mediation of Acacia adaptation to soil salinity: evidence of underlying trade‐offs and tests of expected patterns
Authors: Thrall Peter H. , Bever James D. , Slattery Jo F.
Published: April 2008

The ecological importance of host–soil symbiont associations for plant community structure and dynamics has been recently highlighted, particularly with regard to ecological and evolutionary responses along environmental gradients.

We used a range of native Australian shrubby legumes (Acacia spp.) and associated root‐nodule forming bacteria (rhizobia) in laboratory and glasshouse studies to investigate the ecology of Acacia–rhizobial interactions with respect to soil salinity, a major environmental stressor in many parts of the world.

Analysis of laboratory growth data provided clear evidence of a trade‐off in that growth rate of individual rhizobial isolates was reduced with increasing salt tolerance in culture.

A large replicated glasshouse inoculation trial using 40 strains of rhizobia and nine species of Acacia that varied in their ability to grow in saline soils found strong evidence of host specificity, but neither the average growth promotion of host plants nor the specificity of growth promotion was related to salt tolerance of the isolates.

In a second glasshouse experiment, we used a subset of salt‐sensitive and salt‐tolerant rhizobia and six Acacia species to evaluate performance and symbiotic effectiveness across different levels of soil salinity. Overall, we found no evidence of a relationship between rhizobial salt‐tolerance (as measured in the laboratory) and impact on host growth performance, either in saline or non‐saline soils, and there was no evidence that salt‐tolerant rhizobia perform better in more saline environments.

Synthesis. More salt tolerant Acacia spp. were less responsive in growth to rhizobial inoculation than salt sensitive hosts, implying that evolution towards reduced dependence on the symbiosis may facilitate adaptation to salt, raising a general question regarding the extent to which shifts in dependence on microbial symbionts underlies plant adaptation to other environmental gradients.
Personality traits and temporomandibular disorders in a group of children with bruxing behaviour
Authors: RESTREPO C. C. , VÁSQUEZ L. M. , ALVAREZ M. , VALENCIA I.
Published: April 2008

Summary  The aim of the present study was to compare the personality pattern, the anxiety level and the temporomandibular disorders (TMD) between bruxist and non‐bruxist children with mixed dentition. Fifty‐two subjects, with a mean age of 9·45 years (range 8–11) were evaluated and classified as bruxist (n = 26), according to the American Academy of Sleep Medicine (AASM) and the presence of dental wear clinically visible, under the same conditions of artificial light and position. The control children (n = 26) did not present dental wear and did not accomplished all the AASM criteria. The personality pattern and the anxiety of the bruxist children were studied by means of the Children’s Personality Questionnaire (CPQ) and the Conners’ Parents Rating Scales (CPRS), respectively, and compared with the personality traits and the anxiety level of a non‐bruxist population. The TMD were also evaluated using the Research Diagnostic Criteria for temporomandibular disorders (RDC/TMD) criteria. The data were analysed with the student’s t‐test, Fisher’s exact test and chi‐squared tests. A multivariated analysis was performed using a logistic regression with the stepwise likelihood ratio method. Compared with the controls, the bruxist children had significantly higher tension personality and were more anxiety prone. The bruxist children presented more TMD‐related signs and symptoms than children in the control group. A strong correlation was found among bruxism, TMD, the high anxiety level and the high tension personality trait.
Evaluation of pharyngeal shape and size using anatomical optical coherence tomography in individuals with and without obstructive sleep apnoea
Authors: WALSH JENNIFER H. , LEIGH MATTHEW S. , PADUCH ALEXANDRE , MADDISON KATHLEEN J. , PHILIPPE DANIELLE L. , ARMSTRONG JULIAN J. , SAMPSON DAVID D. , HILLMAN DAVID R. , EASTWOOD PETER R.
Published: April 2008

This study compared shape, size and length of the pharyngeal airway in individuals with and without obstructive sleep apnoea (OSA) using a novel endoscopic imaging technique, anatomical optical coherence tomography (aOCT). The study population comprised a preliminary study group of 20 OSA patients and a subsequent controlled study group of 10 OSA patients and 10 body mass index (BMI)‐, gender‐ and age‐matched control subjects without OSA. All subjects were scanned using aOCT while awake, supine and breathing quietly. Measurements of airway cross‐sectional area (CSA) and anteroposterior (A‐P) and lateral diameters were obtained from the hypo‐, oro‐ and velopharyngeal regions. A‐P : lateral diameter ratios were calculated to provide an index of regional airway shape. In all subjects, pharyngeal CSA was lowest in the velopharynx. Patients with OSA had a smaller velopharyngeal CSA than controls (maximum CSA 91 ± 40 versus 153 ± 84 mm2; P < 0.05) but comparable oro‐ (318 ± 80 versus 279 ± 129 mm2; P = 0.48) and hypopharyngeal CSA (250 ± 105 versus 303 ± 112 mm2; P = 0.36). In each pharyngeal region, the long axis of the airway was oriented in the lateral diameter. Airway shape was not different between the groups. Pharyngeal airway length was similar in both groups, although the OSA group had longer uvulae than the control group (16.8 ± 6.2 versus 11.2 ± 5.2 mm; P < 0.05). This study has shown that individuals with OSA have a smaller velopharyngeal CSA than BMI‐, gender‐ and age‐matched control volunteers, but comparable shape: a laterally oriented ellipse. These findings suggest that it is an abnormality in size rather than shape that is the more important anatomical predictor of OSA.
Calibrating the avian molecular clock
Authors: WEIR J. T. , SCHLUTER D.
Published: April 2008

Molecular clocks are widely used to date phylogenetic events, yet evidence supporting the rate constancy of molecular clocks through time and across taxonomic lineages is weak. Here, we present 90 candidate avian clock calibrations obtained from fossils and biogeographical events. Cross‐validation techniques were used to identify and discard 16 inconsistent calibration points. Molecular evolution occurred in an approximately clock‐like manner through time for the remaining 74 calibrations of the mitochondrial gene, cytochrome b. A molecular rate of approximately 2.1% (± 0.1%, 95% confidence interval) was maintained over a 12‐million‐year interval and across most of 12 taxonomic orders. Minor but significant variance in rates occurred across lineages but was not explained by differences in generation time, body size or latitudinal distribution as previously suggested.
Diverse historical processes shape deep phylogeographical divergence in the pollinating seed parasite Greya politella
Authors: RICH KATHERINE A. , THOMPSON JOHN N. , FERNANDEZ CATHERINE C.
Published: April 2008

Understanding the historical framework in which species interactions have diversified across landscapes may help to partition the effects of vicariance and geographically variable selection in shaping the geographical mosaic of coevolving species. We used phylogeographical analyses of the pollinating seed parasite Greya politella (Lepidoptera: Prodoxidae) to define the historical processes that may have structured interactions of this species with its host plants across major biogeographical breaks in western North America. Using 648 bp of cytochrome oxidase I and amplified fragment length polymorphisims, we identified deep genetic breaks among some populations consistent with some definitions of cryptic species. A combination of phylogenetic and population genetic approaches indicates that different historical processes may have structured G. politella genetic diversity in four regions: northern Pacific Northwest, southern Oregon, southern Sierra Nevada, and the remainder of California. The northern Pacific Northwest had high genetic diversity likely due to glacial refugia and subsequent spatial expansion, concordant with some other taxa. Populations in southern Oregon possessed unique, closely related haplotypes with restricted gene flow, possibly indicating a long‐standing set of populations in this endemic‐rich region. Analyses of California populations showed evidence of restricted gene flow and spatial expansion with many closely related haplotypes that occupy a broad geographical range. Southern Sierra Nevada populations were genetically distinct and highly diverse, possibly due to a localized glacial refugium. Together, these results suggest that vicariance and population expansion, possibly in combination with geographically variable selection, have shaped the diversification of G. politella and its interactions with its host plants.
The electronic bands of CrD, CrH, MgD and MgH: application to the ‘deuterium test’
Authors: Pavlenko Ya. V. , Harris G. J. , Tennyson J. , Jones H. R. A. , Brown J. M. , Hill C. , Yakovina L. A.
Published: April 2008

We compute opacities for the electronic molecular band systems A6Σ+–X6Σ+ of CrH and CrD, and A2Π–X2Σ+ of MgH and MgD. The opacities are computed by making use of existing spectroscopic constants for MgH and CrH. These constants are adjusted for the different reduced masses of MgD and CrD. Frank–Condon factors are used to provide intensities for the individual vibronic bands. These results are used in the computation of synthetic spectra between Teff= 1800 and 1200 K with an emphasis on the realization of ‘deuterium test’, first proposed by Bejar et al. to distinguish brown dwarfs from planetary mass objects. We discuss the possible use of CrD and MgD electronic bands for the ‘deuterium test’. We find CrD to be the more promising of the two deuterides, potentially, the most useful bands of CrH/CrD are the Δv=+1 and Δv=−1 at 0.795 and 0.968 μm.
Physiology of the oesophageal transition zone in the presence of chronic bolus retention: studies using concurrent high resolution manometry and digital fluoroscopy
Authors: Ghosh S. K. , Janiak P. , Fox M. , Schwizer W. , Hebbard G. S. , Brasseur J. G.
Published: April 2008

Abstract  Distinct contraction waves (CWs) exist above and below the transition zone (TZ) between the striated and smooth muscle oesophagus. We hypothesize that bolus transport is impaired in patients with abnormal spatio‐temporal coordination and/or contractile pressure in the TZ. Concurrent high resolution manometry and digital fluoroscopy were performed in healthy subjects and patients with reflux oesophagitis; a condition associated with ineffective oesophageal contractility and clearance. A detailed analysis of space–time variations in bolus movement, intra‐bolus and intra‐luminal pressure was performed on 17 normal studies and nine studies in oesophagitis patients with impaired bolus transit using an interactive computer based system. Compared with normal controls, oesophagitis patients had greater spatial separation between the upper and lower CW tails [median 5.2 cm (range 4.4–5.6) vs 3.1 cm (2.2–3.7)], the average relative pressure within the TZ region (TZ strength) was lower [30.8 mmHg (28.3–36.5) vs 45.8 mmHg (36.1–55.7), P < 0.001], and the risk of bolus retention was higher (90%vs 12%; P < 0.01). The presence of bolus retention was associated with a wider spatial separation of the upper and lower CWs (>3 cm, the upper limit of normal; P < 0.002), independent of the presence of oesophagitis. We conclude that bolus retention in the TZ is associated with excessively wide spatial separation between the upper and lower CWs and lower TZ muscle squeeze. These findings provide a physio‐mechanical basis for the occurrence of bolus retention at the level of the aortic arch, and may underlie impaired clearance with reflux oesophagitis.
Elevated levels of IgG3 and IgG4 subclass in paediatric cases of kala azar
Authors: ANSARI N. A. , KUMAR R. , RAJ A. , SALOTRA P.
Published: April 2008

Visceral leishmaniasis (VL) or Kala azar (KA) is a systemic disease caused by the parasites of the Leishmania donovani complex. Control measures rely on treatment with antileishmanial agents, however, fraught with problems such as toxicity or drug resistance. The incidence rate is on the rise for children, for reasons yet undefined. Previously we have shown significantly elevated level of IL‐10 in children compared to adult KA cases. Here, antileishmanial antibody and C‐reactive protein (CRP) levels were investigated in paediatrics and adult patients of KA and post‐KA dermal leishmaniasis (PKDL). Level of IgG4 was significantly elevated in PKDL compared to KA, although total IgG and IgG1 were significantly lower. The antileishmania antibody levels of subclass IgG3 and IgG4 were found significantly elevated in paediatrics, however, levels of IgG, IgG1, IgG2 and CRP were comparable in paediatric and adult KA cases. In case of PKDL, levels of IgG and it subclass were similar in the two groups. No significant difference in antileishmanial antibody level was noticed between macular or polymorphic cases of PKDL. The differential antibody intensity in paediatric cases, together with significant level of circulating IL‐10, could be considered as a marker of differential disease susceptibility.
Structure and pathogenic variability inAscochyta rabieipopulations on chickpea in the Canadian prairies
Authors: Vail S. , Banniza S.
Published: April 2008

A population study ofAscochyta rabieifrom the Canadian prairies was conducted to assess pathogenicity among isolates with the objectives to investigate the existence of a race or pathotype structure and to evaluate whether there had been a shift to higher aggressiveness between 1998 and 2002. Ninety‐nine isolates collected in 1998, 2001 and 2002 were inoculated onto seven differential chickpea genotypes. Significant isolate × differential interactions occurred, but accounted for a small proportion of the total variability. It was found that very few interaction effects between all combinations of differentials and isolates were significant and frequency distributions of disease severity of isolates tested on the differentials revealed continuous distributions. These results suggest that no genotype‐specific relationship existed betweenA. rabieiand its host and that Canadian populations of the pathogen cannot be objectively classified into races or pathotypes. Isolates from 2001 and 2002 caused significantly more disease than isolates from 1998, suggesting that disease epidemics encountered since 1999 were in part caused by a shift in the population to higher aggressiveness.
Involvement of jasmonic acid signalling in bacterial wilt disease resistance induced by biocontrol agent Pythium oligandrum in tomato
Authors: Hase S. , Takahashi S. , Takenaka S. , Nakaho K. , Arie T. , Seo S. , Ohashi Y. , Takahashi H.
Published: April 2008

When the biocontrol agent Pythium oligandrum (PO) colonizes the rhizosphere, it suppresses bacterial wilt disease in tomato (Solanum lycopersicum cv. Micro‐Tom) caused by Ralstonia solanacearum, and a homogenate of its mycelia exhibits elicitor activity, inducing an ethylene (ET)‐dependent defence response in Micro‐Tom. Since salicylic acid (SA) and jasmonic acid (JA) play an important role in plant defence responses to pathogens, the involvement of SA‐ and JA‐dependent signal transduction pathways in resistance to R. solanacearum was investigated in tomato roots treated with a mycelial homogenate of PO. Bacterial wilt disease was also suppressed in tomato cv. Moneymaker treated with the PO homogenate. However, the SA‐inducible PR‐1(P6) gene was not up‐regulated in either Micro‐Tom or Moneymaker. SA did not accumulate in homogenate‐treated roots in comparison with distilled water‐treated controls, even 24 h after inoculation. Induced resistance against R. solanacearum was not compromised in SA‐non‐accumulating NahG transgenic plants treated with the PO homogenate. On the other hand, the expression of the JA‐responsive gene for the basic PR‐6 protein was induced in both tomato cultivars treated with the PO homogenate. Furthermore, quantitative disease assays showed that the induced resistance against R. solanacearum was compromized in PO homogenate‐treated jai1‐1 mutant plants defective in JA signalling. These results indicated that the JA‐dependent signalling pathway is required for PO‐induced resistance against R. solanacearum in tomato.
Screening for skin carriage of methicillin‐resistant coagulase‐positive staphylococci and Staphylococcus schleiferi in dogs with healthy and inflamed skin
Authors: Griffeth Gregory C. , Morris Daniel O. , Abraham Jill L. , Shofer Frances S. , Rankin Shelley C.
Published: April 2008

Methicillin resistance rates of 41% for Staphylococcus aureus, 16% for S. intermedius, and 40% for S. schleiferi have recently been reported in canine patients. These were deemed to be reflective of referral and clinician‐selection biases, which would imply significantly lower methicillin‐resistant staphylococcal carriage rates in less‐biased canine populations. In this study, swabs for bacterial culture were collected from five cutaneous sites on each of 50 healthy dogs and 59 dogs with inflammatory skin disease to determine prevalence of carriage and relative frequency of methicillin resistance in coagulase‐positive staphylococci and S. schleiferi ssp. schleiferi. These were identified morphologically and by Gram's staining, catalase and coagulase testing, and biochemical speciation. Coagulase‐positive staphylococci and S. schleiferi ssp. schleiferi were isolated from 88% (52 of 59) of affected dogs. Species identified in the culture‐positive dogs were: S. aureus in 12%, S. intermedius (92%), S. schleiferi ssp. schleiferi (10%), and S. schleiferi ssp. coagulans (10%) with methicillin resistance rates of 17%, 8%, 20% and 20%, respectively. Coagulase‐positive staphylococci were isolated from 74% (37 of 50) of healthy dogs: S. aureus (16%), S. intermedius (92%) and S. schleiferi ssp. coagulans (5%). Methicillin resistance rates were 0%, 3% and 50%, respectively. Of total methicillin‐resistant isolates, 11 of 13 were positive for PBP2a via latex agglutination. Methicillin‐resistant S. intermedius and S. schleiferi ssp. schleiferi isolates were all positive for the mecA gene via PCR. There was no significant difference in staphylococcal isolation or methicillin resistance between study groups. While present, methicillin‐resistant coagulase‐positive staphylococci are significantly less common in these less‐biased populations than in the clinical isolates previously reported from this institution which provided the impetus for this study.