bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra-fast underwater suction traps
Authors: Vincent Olivier , Weißkopf Carmen , Poppinga Simon , Masselter Tom , Speck Thomas , Joyeux Marc , Quilliet Catherine , Marmottant Philippe
Published: February 2011

Carnivorous aquaticUtriculariaspecies catch small prey animals using millimetre-sized underwater suction traps, which have fascinated scientists since Darwin's early work on carnivorous plants. Suction takes place after mechanical triggering and is owing to a release of stored elastic energy in the trap body accompanied by a very fast opening and closing of a trapdoor, which otherwise closes the trap entrance watertight. The exceptional trapping speed—far above human visual perception—impeded profound investigations until now. Using high-speed video imaging and special microscopy techniques, we obtained fully time-resolved recordings of the door movement. We found that this unique trapping mechanism conducts suction in less than a millisecond and therefore ranks among the fastest plant movements known. Fluid acceleration reaches very high values, leaving little chance for prey animals to escape. We discovered that the door deformation is morphologically predetermined, and actually performs a buckling/unbuckling process, including a complete trapdoor curvature inversion. This process, which we predict using dynamical simulations and simple theoretical models, is highly reproducible: the traps are autonomously repetitive as they fire spontaneously after 5–20 h and reset actively to their ready-to-catch condition.
Food web structure and biocontrol in a four-trophic level system across a landscape complexity gradient
Authors: Gagic Vesna , Tscharntke Teja , Dormann Carsten F. , Gruber Bernd , Wilstermann Anne , Thies Carsten
Published: February 2011

Decline in landscape complexity owing to agricultural intensification may affect biodiversity, food web complexity and associated ecological processes such as biological control, but such relationships are poorly understood. Here, we analysed food webs of cereal aphids, their primary parasitoids and hyperparasitoids in 18 agricultural landscapes differing in structural complexity (42–93% arable land). Despite little variation in the richness of each trophic group, we found considerable changes in trophic link properties across the landscape complexity gradient. Unexpectedly, aphid–parasitoid food webs exhibited a lower complexity (lower linkage density, interaction diversity and generality) in structurally complex landscapes, which was related to the dominance of one aphid species in complex landscapes. Nevertheless, primary parasitism, as well as hyperparasitism, was higher in complex landscapes, with primary parasitism reaching levels for potentially successful biological control. In conclusion, landscape complexity appeared to foster higher parasitism rates, but simpler food webs, thereby casting doubt on the general importance of food web complexity for ecosystem functioning.
Ignoring the challenge? Male black redstarts (
Phoenicurus ochruros
) do not increase testosterone levels during territorial conflicts but they do so in response to gonadotropin-releasing hormone
Authors: Apfelbeck Beate , Goymann Wolfgang
Published: February 2011

Competition elevates plasma testosterone in a wide variety of vertebrates, including humans. The ‘challenge hypothesis’ proposes that seasonal peaks in testosterone during breeding are caused by social challenges from other males. However, during experimentally induced male–male conflicts, testosterone increases only in a minority of songbird species tested so far. Why is this so? Comparative evidence suggests that species with a short breeding season may not elevate testosterone levels during territory defence. These species may even be limited in their physiological capability to increase testosterone levels, which can be tested by injecting birds with gonadotropin-releasing hormone (GnRH). We studied two populations of black redstarts that differ in breeding altitude, morphology and the length of their breeding season. Unexpectedly, males of neither population increased testosterone in response to a simulated territorial intrusion, but injections with GnRH resulted in a major elevation of testosterone. Thus, black redstarts would have been capable of mounting a testosterone response during the male–male challenge. Our data show, for the first time, that the absence of an androgen response to male–male challenges is not owing to physiological limitations to increase testosterone. Furthermore, in contrast to comparative evidence between species, populations of black redstarts with a long breeding season do not show the expected elevation in testosterone during male–male challenges.
The Vibrio cholerae VarS/VarA two-component system controls the expression of virulence proteins through ToxT regulation
Authors: Jang Jeyoun , Jung Kyung-Tae , Park Jungchan , Yoo Cheon-Kwon , Rhie Gi-Eun
Published: February 2011

Although the conditions for inducing virulence protein expression in vitro are different, both classical and El Tor biotypes of Vibrio cholerae have been reported to regulate the expression of virulence proteins such as cholera toxin (CT) and toxin-coregulated pili (Tcp) through the ToxR/S/T system. The transcription activator ToxR responds to environmental stimuli such as pH and temperature and activates the second transcriptional regulator ToxT, which upregulates expression of virulence proteins. In addition to the ToxR/S/T signalling system, V. cholerae has been proposed to utilize another two-component system VarS/VarA to modulate expression of virulence genes. Previous study has shown that VarA of the VarS/VarA system is involved in the regulation of virulence proteins in the classical V. cholerae O395 strain; however, no further analysis was performed concerning VarS. In this study, we constructed varS mutants derived from the classical O395 and El Tor C6706 strains and demonstrated that VarS is also involved in the expression of the virulence proteins CT and Tcp from the V. cholerae classical and El Tor strains. This expression is through regulation of ToxT expression in response to environmental changes due to different toxin-inducing conditions.
JNK regulates FoxO-dependent autophagy in neurons
Authors: Xu Ping , Das Madhumita , Reilly Judith , Davis Roger J.
Published: February 2011

The cJun N-terminal kinase (JNK) signal transduction pathway is implicated in the regulation of neuronal function. JNK is encoded by three genes that play partially redundant roles. Here we report the creation of mice with targeted ablation of all three Jnk genes in neurons. Compound JNK-deficient neurons are dependent on autophagy for survival. This autophagic response is caused by FoxO-induced expression of Bnip3 that displaces the autophagic effector Beclin-1 from inactive Bcl-XL complexes. These data identify JNK as a potent negative regulator of FoxO-dependent autophagy in neurons.
RNase E action at a distance: degradation of target mRNAs mediated by an Hfq-binding small RNA in bacteria: Figure 1.
Authors: Morita Teppei , Aiba Hiroji
Published: February 2011

A major class of bacterial small RNAs (sRNAs), along with RNA-binding protein Hfq and endoribonuclease RNase E, acts on target mRNAs through base-pairing, leading to translational repression and rapid degradation of the mRNAs. In this issue of Genes & Development, Prévost and colleagues (pp. 385–396) demonstrate by using the well-characterized sRNA RyhB that RNase E cleavage at sites distal from the pairing region triggers degradation of target mRNAs. The study has provided an important insight into the initial events of sRNA-induced degradation of target mRNAs.
Production of Viable Gametes without Meiosis in Maize Deficient for an ARGONAUTE Protein
Authors: Singh Manjit , Goel Shalendra , Meeley Robert B. , Dantec Christelle , Parrinello Hugues , Michaud Caroline , Leblanc Olivier , Grimanelli Daniel
Published: February 2011

Apomixis is a form of asexual reproduction through seeds in angiosperms. Apomictic plants bypass meiosis and fertilization, developing offspring that are genetically identical to their mother. In a genetic screen for maize (Zea mays) mutants mimicking aspects of apomixis, we identified a dominant mutation resulting in the formation of functional unreduced gametes. The mutant shows defects in chromatin condensation during meiosis and subsequent failure to segregate chromosomes. The mutated locus codes for AGO104, a member of the ARGONAUTE family of proteins. AGO104 accumulates specifically in somatic cells surrounding the female meiocyte, suggesting a mobile signal rather than cell-autonomous control. AGO104 is necessary for non-CG methylation of centromeric and knob-repeat DNA. Digital gene expression tag profiling experiments using high-throughput sequencing show that AGO104 influences the transcription of many targets in the ovaries, with a strong effect on centromeric repeats. AGO104 is related to Arabidopsis thaliana AGO9, but while AGO9 acts to repress germ cell fate in somatic tissues, AGO104 acts to repress somatic fate in germ cells. Our findings show that female germ cell development in maize is dependent upon conserved small RNA pathways acting non-cell-autonomously in the ovule. Interfering with this repression leads to apomixis-like phenotypes in maize.
Oxidative DNA Damage Bypass in Arabidopsis thaliana Requires DNA Polymerase λ and Proliferating Cell Nuclear Antigen 2
Authors: Amoroso Alessandra , Concia Lorenzo , Maggio Caterina , Raynaud Cécile , Bergounioux Catherine , Crespan Emmanuele , Cella Rino , Maga Giovanni
Published: February 2011

The oxidized base 7,8-oxoguanine (8-oxo-G) is the most common DNA lesion generated by reactive oxygen species. This lesion is highly mutagenic due to the frequent misincorporation of A opposite 8-oxo-G during DNA replication. In mammalian cells, the DNA polymerase (pol) family X enzyme DNA pol λ catalyzes the correct incorporation of C opposite 8-oxo-G, together with the auxiliary factor proliferating cell nuclear antigen (PCNA). Here, we show that Arabidopsis thaliana DNA pol λ, the only member of the X family in plants, is as efficient in performing error-free translesion synthesis past 8-oxo-G as its mammalian homolog. Arabidopsis, in contrast with animal cells, possesses two genes for PCNA. Using in vitro and in vivo approaches, we observed that PCNA2, but not PCNA1, physically interacts with DNA pol λ, enhancing its fidelity and efficiency in translesion synthesis. The levels of DNA pol λ in transgenic plantlets characterized by overexpression or silencing of Arabidopsis POLL correlate with the ability of cell extracts to perform error-free translesion synthesis. The important role of DNA pol λ is corroborated by the observation that the promoter of POLL is activated by UV and that both overexpressing and silenced plants show altered growth phenotypes.
Mutation of RiceBC12/GDD1, Which Encodes a Kinesin-Like Protein That Binds to a GA Biosynthesis Gene Promoter, Leads to Dwarfism with Impaired Cell Elongation
Authors: Li Juan , Jiang Jiafu , Qian Qian , Xu Yunyuan , Zhang Cui , Xiao Jun , Du Cheng , Luo Wei , Zou Guoxing , Chen Mingluan , Huang Yunqing , Feng Yuqi , Cheng Zhukuan , Yuan Ming , Chong Kang
Published: February 2011

The kinesins are a family of microtubule-based motor proteins that move directionally along microtubules and are involved in many crucial cellular processes, including cell elongation in plants. Less is known about kinesins directly regulating gene transcription to affect cellular physiological processes. Here, we describe a rice (Oryza sativa) mutant, gibberellin  -deficient dwarf1 (gdd1), that has a phenotype of greatly reduced length of root, stems, spikes, and seeds. This reduced length is due to decreased cell elongation and can be rescued by exogenous gibberellic acid (GA3) treatment. GDD1 was cloned by a map-based approach, was expressed constitutively, and was found to encode the kinesin-like protein BRITTLE CULM12 (BC12). Microtubule cosedimentation assays revealed that BC12/GDD1 bound to microtubules in an ATP-dependent manner. Whole-genome microarray analysis revealed the expression of ent-kaurene oxidase (KO2), which encodes an enzyme involved in GA biosynthesis, was downregulated in gdd1. Electrophoretic mobility shift and chromatin immunoprecipitation assays revealed that GDD1 bound to the element ACCAACTTGAA in the KO2 promoter. In addition, GDD1 was shown to have transactivation activity. The level of endogenous GAs was reduced in gdd1, and the reorganization of cortical microtubules was altered. Therefore, BC12/GDD1, a kinesin-like protein with transcription regulation activity, mediates cell elongation by regulating the GA biosynthesis pathway in rice.
Science and alcohol policy: a case study of the EU Strategy on Alcohol
Authors: Gordon Rebecca , Anderson Peter
Published: February 2011

Aims To describe the extent to which the content of the European Commission's Communication on alcohol reflects public health‐based scientific evidence.

Design Document retrieval and content analysis.

Setting European Union.

Participants Background documents leading up to the European Commission's Communication on alcohol, the Communication itself and implementation actions following the Communication.

Measurements Documents were read and analyzed for evidence‐based alcohol policy content.

Findings Although the Communication acknowledges and supports existing interventions which have high evidence for effectiveness, such as enforcing blood alcohol concentration (BAC) limits for drivers, it extensively promotes other interventions which have been shown to be ineffective; for example, recommending education and persuasion strategies as a measure across all its five priority areas. Measures to influence price are mentioned only once in relation to sales in drinking venues limiting two‐for‐one drinks offers. Measures to control physical availability are mentioned infrequently.

Conclusions The Communication reflects the science, in that it acknowledges the significance of alcohol as a social and health determinant in Europe. However, it places more emphasis on policy actions with less evidence for effectiveness than on those with strong evidence. It also focuses its efforts more on mapping member state actions and coordinating knowledge exchange than on providing concrete recommendations for action or developing Europe‐wide policy measures. This may be a compromise between the rights of Member States to develop national policy and legislation and the obligation of the European Union as a collaborative body to protect health. Furthermore, it has been suggested that the European Union's roots as a trading block emphasizes collaboration with industry stakeholders and this influences the ability to prioritize health over trade considerations.
Do infrastructures impact on alcohol policy making?
Authors: König Claudia , Segura Lidia
Published: February 2011

Introduction The importance of building and strengthening effective infrastructures within the field of public health has increasingly been recognized. A wide variety of actors and structures can be identified for alcohol policy, including systems for policy development, monitoring, research and work‐force development, but too little is known about the complex systems of infrastructure available across European countries and their impact on alcohol policy.

Objective This study is part of the Alcohol Measures for Public Health Research Alliance (AMPHORA) project, and aims to map existing infrastructures, but also to examine the relationship between infrastructures and alcohol policy change.

Methods A survey of alcohol policy infrastructure and infrastructure needs at the national level will be conducted using an updated and adapted questionnaire based on the Health Promotion (HP) Source Project tool. Case studies involving in‐depth interviews will be conducted for a selection of countries. Data will be analysed descriptively, mapping alcohol policy infrastructure and identifying needs to reveal any relationship between infrastructure and alcohol policy.

Expected results This study can contribute to building the scientific knowledge base on this topic as well to policy development. First, the Alcohol Measures for Public Health Research Alliance will produce an extended map of alcohol policy infrastructures in a wide range of European countries. Secondly, the Alcohol Measures for Public Health Research Alliance will foster a better understanding and expand the knowledge base on the role and influence of infrastructure on alcohol policy and practice. Recommendations deriving from this study will identify the need for better utilization of existing infrastructures and for the development of new infrastructures, necessary to develop and implement effective alcohol policy from a public health perspective.
Epidemiology and alcohol policy in Europe
Authors: Rehm Jürgen , Zatonksi Witold , Taylor Ben , Anderson Peter
Published: February 2011

Aims  To describe three aspects of the epidemiology of alcohol‐attributable deaths in Europe, dose, demography and place, and to illustrate how such knowledge can better be used to inform alcohol policy formulation and implementation.

Design  epidemiological and population health modeling.

Setting  Europe.

Participants  Based on country‐specific aggregate statistics.

Measurements  Exposure: country‐specific adult per capita consumption triangulated with survey data; outcomes: mortality statistics.

Findings  The absolute risk of dying from an alcohol‐attributable disease and injury (accounting for a protective effect for ischaemic diseases) increases with increasing daily alcohol consumption beyond 10g alcohol per day, the first data point. Over 2/3 of all alcohol‐attributable deaths occurring amongst the 20–64 year old population of the European Union (minus Cyprus and Malta) occur in the 45–64 year olds. About 25% of the difference in life expectancy between western and eastern Europe for men aged 20–64 years in 2002 can be attributed to alcohol, largely, but not exclusively, as a result of differences in heavy episodic drinking patterns.

Conclusions  Any reduction in the dose of alcohol consumed, at least down to 10g/day, will reduce the annual and lifetime risk of an alcohol‐related death. There is a need for alcohol policy to focus on measures in reducing alcohol consumption, throughout middle age, with immediacy of impact. Policy should strive to reduce alcohol‐related health inequalities, with the specific recommendations for policy depending on the cost‐effectiveness of interventions related to the epidemiological profile of the country or region under consideration. Fortunately, there are evidence‐based policy options that reduce the amount of alcohol consumed and many alcohol‐related harms with immediate effect, that reduce the risk of an alcohol‐related death in middle age, and that would help to close the health gap between eastern and western Europe.
Identifying the gap between need and intervention for alcohol use disorders in Europe
Authors: Drummond Colin , Gual Antoni , Goos Cees , Godfrey Christine , Deluca Paolo , Von Der Goltz Christoph , Gmel Gerhard , Scafato Emanuele , Wolstenholme Amy , Mann Karl , Coulton Simon , Kaner Eileen
Published: February 2011

Aims  A literature review of existing research on the prevalence of alcohol use disorders (AUDs) and availability of alcohol interventions in Europe was conducted. The review also explored what is known about the gap between need and provision of alcohol interventions in Europe.

Methods  The review search strategy included: (i) descriptive studies of alcohol intervention systems in Europe; (ii) studies of alcohol service provision in Europe; and (iii) studies of prevalence of AUD and alcohol needs assessment in Europe.

Results  Europe has a relatively high level of alcohol consumption and the resulting disabilities are the highest in the world. Most research on implementation of alcohol interventions in Europe has been restricted to screening and brief interventions. Alcohol needs assessment methodology has been developed but has not been applied in comparative studies across countries in Europe.

Conclusions  This review points to key gaps in knowledge related to alcohol interventions in Europe. There is a lack of comparative data on variations in alcohol treatment systems across European countries and there is also a lack of comparative data on the prevalence of alcohol use disorders across European countries and the relative gap between need and access to treatment. The forthcoming Alcohol Measures for Public Health Research Alliance (AMPHORA) research project work package on ‘Early identification and treatment’ aims to address these gaps.
Reflections on science and the governance of alcohol policy
Authors: Anderson Peter , Gual Antoni
Published: February 2011

Aims  To consider, briefly, science's role in informing alcohol policy, and how science could help reframe the present governance of alcohol policy.

Design  Expression of the two project coordinators’ reflections based on discussions during project meetings of the Alcohol Measures for Public Health Research Alliance (AMPHORA) project.

Results  Three endeavours are considered important for science's role in informing alcohol policy: modelling studies that help predict the outcomes of differing policy approaches; studying the impact of live policy changes as a powerful set of natural experiments; and, improved study of the impact of integrated, coordinated and joined up alcohol policies, as opposed to the impact of individual alcohol policy measures. Three areas where science can contribute to strengthened alcohol policy governance include: analysis of different governance architectures that might promote joined‐up actions between different sectors; the design of better metrics that measure the impact of public and private sector actions on health; and, by identifying incentives that help consumers make choices on the use of alcohol that improve health.

Conclusions  The impact of science on better alcohol policy governance can only happen if there is more and better dialogue between scientists and those who design alcohol policy.
Past lessons and future prospects: plant breeding for yield and persistence in cool‐temperate pastures
Authors: Parsons A. J. , Edwards G. R. , Newton P. C. D. , Chapman D. F. , Caradus J. R. , Rasmussen S. , Rowarth J. S.
Published: February 2011

Pastoral‐based animal production systems are under increasing pressure to provide the high quantity and quality of feed needed for optimal ruminant performance. The capacity of farmers to increase forage yield further, solely by increasing fertilizer inputs or through improved pasture management, is limited. Emerging requirements to balance industry production targets against the need to reduce greenhouse gas emissions and N losses pose further challenges. Plant breeding is being asked to deliver results more urgently than at any time previously, and this review attempts to highlight issues that might limit the prospects for future progress by seeking lessons from four past examples: (i) white clover breeding gains and the need to consider the complexity of the grazed grass‐clover mixed sward, with its tendency for cycling in plant species composition; (ii) a systems field trial of new and old grass/clover cultivars, and how the complexity of growth of perennial forage crops, and the dynamic optimality required for sustainable harvesting might limit our ability to breed for ‘yield’per se; (iii) the manipulation of a physiological trait (low ‘maintenance’ respiration) and the implications of such changes for plant fitness and G × E interactions; and (iv) an hypothesis‐driven development of a trait (high‐sugar grasses) and the value of ‘proof of concept’ studies, the requirement of scientific understanding of the mechanisms of trait expression, and how one might in future go about assessing breeding achievements. We discuss the general ecological considerations around shifts in the frequency distribution of traits in new populations, whether altered conventionally or by genetic modification, and how selection for a particular trait might inadvertently reduce both fitness and persistence. A major priority for breeding, we propose, might be to revisit previously abandoned traits that affected the physiological performance of forage species, armed now with a capacity to monitor gene expression at the molecular level, and so unravel/control the G × E interactions that limited their benefits. We also discuss how a ‘loss of yield advantage’ of new cultivars, seen when tested several years after sowing, requires urgent investigation and propose this might be associated with fitness costs of perenniality. Finally, we argue for a careful reconsideration of what are realistic expectations for systems field trials and that focus on forage breeding might be shifted more to ‘proof of concept’ studies, critical experimental design, comparing ‘traits’ rather than ‘cultivars’, and the wider ecological assessment of fitness and function of traits in the plant, community and ecosystem.
Handling of radical prostatectomy specimens: total or partial embedding?
Authors: Vainer Ben , Toft Birgitte Grønkær , Olsen Karen Ege , Jacobsen Grete Krag , Marcussen Niels
Published: February 2011

Vainer B, Toft B G, Olsen K E, Jacobsen G K & Marcussen N (2011) Histopathology58, 211–216 Handling of radical prostatectomy specimens: total or partial embedding?

Aims:  Proper examination and accurate reporting of radical prostatectomy specimens (RPS) is essential in determining post‐surgical treatment and predicting patient outcome. Surveys have demonstrated the absence of consensus on handling of RPS. The aim of this study was to determine whether significant information is lost when only half the horizontal tissue sections are examined.

Methods and results:  During a 1‐year period, 238 RPS were sectioned into horizontal slices. Apex and basis was cut sagittally, and remaining slices were embedded in quadrants. Glass slides from every second horizontal slice were withheld. The remaining slides were evaluated microscopically, and essential pathological parameters were recorded. Subsequently, a full report was compiled, including the withheld slides. A median of 12 slides (30%) were withheld during initial assessment. In eight RPS (3.2%) the pTNM stage had to be changed; in six cases (2.6%) from pT2b to pT2c and in two cases (0.8%) from pT2c to pT3a. In one RPS (0.4%) the surgical margin status was changed.

Conclusions:  Only little information is lost with systematic partial embedding, overlooking features significant for the postoperative treatment in only 1.2%. Partial embedding as suggested, decreasing the laboratory workload by 30%, is concluded to be acceptable for valid histopathological assessment.
Cluster analysis of immunohistochemical profiles delineates CK7, vimentin, S100A1 and C‐kit (CD117) as an optimal panel in the differential diagnosis of renal oncocytoma from its mimics
Authors: Carvalho Jason C , Wasco Matthew J , Kunju Lakshmi P , Thomas Dafydd G , Shah Rajal B
Published: February 2011

Carvalho J C, Wasco M J, Kunju L P, Thomas D G & Shah R B (2011) Histopathology58, 169–179

Cluster analysis of immunohistochemical profiles delineates CK7, vimentin, S100A1 and C‐kit (CD117) as an optimal panel in the differential diagnosis of renal oncocytoma from its mimics

Aims:  To develop an immunohistochemical strategy for distinguishing renal oncocytoma (RO) from the eosinophilic variant of chromophobe (ChRCC), and papillary (PRCC) and clear cell (CRCC) renal cell carcinoma containing eosinophilic cytoplasm in core biopsy specimens.

Methods and results:  Cluster analysis was performed on immunohistochemical data from 21 RO, 16 ChRCC, 16 CRCC and 20 PRCC patients. A panel of CK7, C‐kit, S100A1 and vimentin clustered into four groups. Cluster A (94% ChRCC) expressed C‐kit and CK7 and lacked S100A1 and vimentin. Cluster B (95% RO) expressed C‐kit, S100A1, focal CK7 (single or small clusters of cells) and lacked vimentin. Cluster C comprised a mixture of PRCC and CRCC with no expression of C‐kit or CK7 and variable S100A1 and vimentin. PRCC with strong expression of CK7 clustered into group D. A panel of S100A1 (positive) and focal CK7 expression distinguished RO from ChRCC with 91% sensitivity and 93% specificity. A panel of vimentin (negative) and C‐kit (positive) distinguished RO from CRCC with 83% sensitivity and 86% specificity and RO from PRCC with 79% sensitivity and 88% specificity.

Conclusions:  Hierarchical cluster analysis is an effective approach to analyse high‐volume immunohistochemical data to generate an optimal panel in the differential diagnosis of oncocytoma from its mimics.
Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma
Authors: Souza Ludmilla R , Fonseca‐Silva Thiago , Pereira Camila S , Santos Erivelton P , Lima Lucianne C , Carvalho Heloísa A , Gomez Ricardo S , Guimarães André L S , De Paula Alfredo M B
Published: February 2011

Souza L R, Fonseca‐Silva T, Pereira C S, Santos E P, Lima L C, Carvalho H A, Gomez R S, Guimarães A L S & De Paula A M B (2011) Histopathology58, 352–360 Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma

Aims:  This study has compared the tissue expression of the p53 tumour suppressor protein and DNA repair proteins APE1, hMSH2 and ERCC1 in normal, dysplastic and malignant lip epithelium.

Methods and results:  Morphological analysis and immunohistochemistry were performed on archived specimens of normal lip mucosa (n = 15), actinic cheilitis (AC) (n = 30), and lip squamous cell carcinoma (LSCC) (n = 27). AC samples were classified morphologically according to the severity of epithelial dysplasia and risk of malignant transformation. LSCC samples were morphologically staged according to WHO and invasive front grading (IFG) criteria. Differences between groups and morphological stages were determined by bivariate statistical analysis. Progressive increases in the percentage of epithelial cells expressing p53 and APE1 were associated with increases in morphological malignancy from normal lip mucosa to LSCC. There was also a significant reduction in epithelial cells expressing hMSH2 and ERCC1 proteins in the AC and LSCC groups. A higher percentage of malignant cells expressing APE1 was found in samples with an aggressive morphological IFG grade.

Conclusions:  Our data showed that epithelial cells from premalignant to malignant lip disease exhibited changes in the expression of p53, APE1, hMSH2 and ERCC1 proteins; these molecular change might contribute to lip carcinogenesis.
HER2 status in gastro‐oesophageal adenocarcinomas assessed by two rabbit monoclonal antibodies (SP3 and 4B5) and two in situ hybridization methods (FISH and SISH)
Authors: Boers James E. , Meeuwissen Harriëtte , Methorst Natalie
Published: February 2011

Boers J E, Meeuwissen H & Methorst N (2011) Histopathology58, 383–394 HER2 status in gastro‐oesophageal adenocarcinomas assessed by two rabbit monoclonal antibodies (SP3 and 4B5) and two in situ hybridization methods (FISH and SISH)

Aims:  HER2 gene amplification has been detected in 10–20% of gastric adenocarcinomas. In view of the recently demonstrated clinical benefit of the anti‐human epidermal growth factor receptor 2 (HER2) drug trastuzumab in the treatment of advanced gastric cancer, reliable HER2 testing is of key importance. The aim of this study was to examine HER2 status in gastro‐oesophageal adenocarcinomas comparing SP3 and 4B5 immunohistochemistry (IHC) with dual probe HER2 [fluorescence in situ hybridization (FISH) and silver in situ hybridization (SISH)].

Methods and results:  IHC and SISH were carried out on biopsy specimens of 146 patients with adenocarcinomas of the oesophagus and stomach. All SP3‐IHC‐positive cases and 91% of 4B5‐IHC‐positive cases were amplified. Sensitivity of SP3‐IHC‐positivity and 4B5‐IHC‐positivity for amplification was 77% and 96%, respectively. Results of FISH performed in 42 cases were identical to SISH. Amplification was heterogeneous in 73% of the adenocarcinomas; 24% of the oesophago‐gastric carcinomas and 7% of distal stomach tumours were amplified.

Conclusions:  HER2‐positivity is present in a significant proportion of oesophago‐gastric adenocarcinomas (24%), but at a lower rate in the distal stomach (7%). Sensitivity for amplification is higher with 4B5 IHC than with SP3. FISH and SISH yield identical results, but assessment is much easier with SISH. Our findings provide important guidance for HER2‐testing in gastro‐oesophageal adenocarcinomas for patients in whom anti‐HER2 treatment is considered.
Human IgG isotypes and activating Fcγ receptors in the interaction of Salmonella enterica serovar Typhimurium with phagocytic cells
Authors: Goh Yun S. , Grant Andrew J. , Restif Olivier , McKinley Trevelyan J. , Armour Kathryn L. , Clark Michael R. , Mastroeni Pietro
Published: February 2011

Several classes and multiple subclasses of immunoglobulins are produced towards protein and polysaccharide antigens in response to Salmonella infection and play a key role in protection against systemic disease. The targeting of Salmonella to Fc receptors (FcR) on phagocytes is a key step in the antibody‐mediated antibacterial functions of host cells. We wished to compare the relative efficiency of different human IgG subclasses, which targeted the Salmonella enterica OmpA surface protein in modulating the interaction of bacteria with human phagocytes. To this end, we developed a novel system by tagging OmpA with a foreign CD52 mimotope (TSSPSAD) and opsonizing the bacteria with a panel of humanized CD52 antibodies that share the same antigen‐binding V‐region, but have constant regions of different subclasses. Our data revealed that opsonization with all the IgG subclasses increases Salmonella uptake by human phagocytes. IgG3 resulted in the highest level of bacterial uptake and the highest average bacterial load per infected cell, which was closely followed by IgG1, then IgG4 and lastly IgG2. Phagocytosis mediated by IgG1, IgG3 and IgG4 had a higher dependency on FcγRI than FcγRIIA, whereas IgG2‐mediated phagocytosis required FcγRIIA more than FcγRI. The results show that IgG binding to OmpA increases the uptake of Salmonella by human phagocytic cells and that the efficiency of this process depends both on the subclass of the IgG and the type of FcR that is available for antibody binding.
Hull fouling as an invasion vector: can simple models explain a complex problem?
Authors: Sylvester Francisco , Kalaci Odion , Leung Brian , Lacoursière‐Roussel Anaïs , Murray Cathryn Clarke , Choi Francis M. , Bravo Monica A. , Therriault Thomas W. , MacIsaac Hugh J.
Published: February 2011

1. The most effective way to manage nonindigenous species and their impacts is to prevent their introduction via vector regulation. While ships’ ballast water is very well studied and this vector is actively managed, hull fouling has received far less attention and regulations are only now being considered despite its importance for introductions to coastal, marine systems.

2. We conducted comprehensive in situ sampling and video recording of hulls of 40 transoceanic vessels to assess propagule and colonization pressure in Vancouver and Halifax, dominant coastal ports in Canada. Concomitant sampling was conducted of harbour fouling communities to compare hull and port communities as part of a vector risk assessment.

3. Although this vector has been operational for a long time, hull and harbour communities were highly divergent, with mean Sørensen’s similarity values of 0·03 in Halifax and 0·01 in Vancouver, suggesting invasion risk is high. Propagule pressure (up to 600 000 ind. ship−1) and colonization pressure (up to 156 species ship−1) were high and varied significantly between ports, with Vancouver receiving much higher abundances and diversity of potential invaders. The higher risk of fouling introductions in Vancouver is consistent with historical patterns of successful hull fouling invasions.

4. The extent of hull fouling was modelled using ship history predictors. Propagule pressure increased with time spent in previous ports‐of‐call and time since last application of antifouling paint, whereas colonization pressure increased with time since last painting and with the number of regions visited by the ship. Both propagule and colonization pressure were negatively related to the time spent at sea and the latitude of ports visited.

5. Synthesis and applications. A major challenge for applied invasion ecology is the effective management of introduction vectors. We found that hull fouling has a strong potential for introduction of many species to coastal marine habitats and that management should be considered. Simple variables related to the vessels’ hull husbandry, voyage, and sailing patterns may be used to predict and manage hull fouling intensity. The results presented here should interest policy makers and environmental managers who seek to reduce invasion risk, and ship owners seeking to optimize fuel efficiency.
A genomically tractable and ecologically relevant model herbivore for a model plant: new insights into the mechanisms of insect–plant interactions and evolution
Authors: GIRON DAVID , HUGUET ELISABETH
Published: February 2011

The availability of model microbial pathogens and plants has been key to characterizing resistance and virulence pathways and to shedding light on the mechanisms of host–parasite interactions and co‐evolution (e.g. Allen et al. 2004, Science306, 1957–1960; Bergelson et al. 2001, Science292, 2281–2285). However, the absence of genetically tractable arthropod parasites of model plants has impeded so far our ability to gain better insights into the mechanisms, evolution and ecological consequences of plant–herbivore interactions. In this issue of Molecular Ecology, Whiteman et al. (2011) highlight fascinating features of a drosophilid fly, Scaptomyza flava, that feeds on the model plant Arabidopsis thaliana. They explore the potential of this system for studying insect–plant interactions with a clever mix of phenotypic and genetic experiments providing a comprehensive and persuasive argument for the validity of this model system. This study sets the ground for key developments in the unravelling of mechanisms involved in (i) plant–insect interactions and co‐evolution, and (ii) transition to herbivory in arthropods and evolution of endophagous lifestyles.
Population structure of mycobionts and photobionts of the widespread lichen Cetraria aculeata
Authors: FERNÁNDEZ‐MENDOZA F. , DOMASCHKE S. , GARCÍA M. A. , JORDAN P. , MARTÍN M. P. , PRINTZEN C.
Published: February 2011

Lichens are symbioses between fungi (mycobionts) and photoautotrophic green algae or cyanobacteria (photobionts). Many lichens occupy large distributional ranges covering several climatic zones. So far, little is known about the large‐scale phylogeography of lichen photobionts and their role in shaping the distributional ranges of lichens. We studied south polar, temperate and north polar populations of the widely distributed fruticose lichen Cetraria aculeata. Based on the DNA sequences from three loci for each symbiont, we compared the genetic structure of mycobionts and photobionts. Phylogenetic reconstructions and Bayesian clustering methods divided the mycobiont and photobiont data sets into three groups. An amova shows that the genetic variance of the photobiont is best explained by differentiation between temperate and polar regions and that of the mycobiont by an interaction of climatic and geographical factors. By partialling out the relative contribution of climate, geography and codispersal, we found that the most relevant factors shaping the genetic structure of the photobiont are climate and a history of codispersal. Mycobionts in the temperate region are consistently associated with a specific photobiont lineage. We therefore conclude that a photobiont switch in the past enabled C. aculeata to colonize temperate as well as polar habitats. Rare photobiont switches may increase the geographical range and ecological niche of lichen mycobionts by associating them with locally adapted photobionts in climatically different regions and, together with isolation by distance, may lead to genetic isolation between populations and thus drive the evolution of lichens.
Plant systems biology: network matters
Authors: LUCAS MIKAËL , LAPLAZE LAURENT , BENNETT MALCOLM J.
Published: February 2011

Systems biology is all about networks. A recent trend has been to associate systems biology exclusively with the study of gene regulatory or protein‐interaction networks. However, systems biology approaches can be applied at many other scales, from the subatomic to the ecosystem scales. In this review, we describe studies at the sub‐cellular, tissue, whole plant and crop scales and highlight how these studies can be related to systems biology. We discuss the properties of system approaches at each scale as well as their current limits, and pinpoint in each case advances unique to the considered scale but representing potential for the other scales. We conclude by examining plant models bridging different scales and considering the future prospects of plant systems biology.
Role of PSBS and LHCSR in Physcomitrella patens acclimation to high light and low temperature
Authors: GEROTTO CATERINA , ALBORESI ALESSANDRO , GIACOMETTI GIORGIO M. , BASSI ROBERTO , MOROSINOTTO TOMAS
Published: February 2011

Photosynthetic organisms respond to strong illumination by activating several photoprotection mechanisms. One of them, non‐photochemical quenching (NPQ), consists in the thermal dissipation of energy absorbed in excess. In vascular plants NPQ relies on the activity of PSBS, whereas in the green algae Chlamydomonas reinhardtii it requires a different protein, LHCSR. The moss Physcomitrella patens is the only known organism in which both proteins are present and active in triggering NPQ, making this organism particularly interesting for the characterization of this protection mechanism. We analysed the acclimation of Physcomitrella to high light and low temperature, finding that these conditions induce an increase in NPQ correlated to overexpression of both PSBS and LHCSR. Mutants depleted of PSBS and/or LHCSR showed that modulation of their accumulation indeed determines NPQ amplitude. All mutants with impaired NPQ also showed enhanced photosensitivity when exposed to high light or low temperature, indicating that in this moss the fast‐responding NPQ mechanism is also involved in long‐term acclimation.
Resistance to Rhizoctonia solani AG‐2‐2 (IIIB) in creeping bentgrass plants transformed with pepper esterase gene PepEST
Authors: Cho K.‐C. , Han Y.‐J. , Kim S.‐J. , Lee S.‐S. , Hwang O.‐J. , Song P.‐S. , Kim Y.‐S. , Kim J.‐I.
Published: February 2011

A pepper esterase (PepEST) gene was introduced into creeping bentgrass (Agrostis stolonifera) by Agrobacterium‐mediated transformation. Purified recombinant PepEST proteins were sufficient to inhibit the growth of the fungal pathogens Rhizoctonia solani AG2‐2 (IIIB) (causing brown patch) and Sclerotinia homoeocarpa (dollar spot), but not the oomycete responsible for pythium blight, Pythium aphanidermatum. PepEST proteins were most effective against R. solani. After genetic transformation of creeping bentgrass with PepEST, the genomic integration of transgenes bar and PepEST was confirmed by Southern blot analysis, and their expression was also validated by northern blot and western blot analyses. Disease severity on R. solani‐inoculated leaves of transgenic plants was <10% compared to ca. 50% in non‐transgenic plants. Microscopic observation of infected leaves indicated that PepEST inhibited the growth of hyphae upon fungal infection.
Ghrelin receptor (GHS‐R1A) antagonism suppresses both operant alcohol self‐administration and high alcohol consumption in rats
Authors: Landgren Sara , Simms Jeffrey A. , Hyytiä Petri , Engel Jörgen A. , Bartlett Selena E. , Jerlhag Elisabet
Published: February 2011

The mechanisms involved in alcohol use disorders are complex. It has been shown that ghrelin is an important signal for the control of body weight homeostasis, preferably by interacting with hypothalamic circuits, as well as for drug reward by activating the mesolimbic dopamine system. The ghrelin receptor (GHS‐R1A) has been shown to be required for alcohol‐induced reward. Additionally, ghrelin increases and GHR‐R1A antagonists reduce moderate alcohol consumption in mice, and a single nucleotide polymorphism in the GHS‐R1A gene has been associated with high alcohol consumption in humans. However, the role of central ghrelin signaling in high alcohol consumption is not known. Therefore, the role of GHS‐R1A in operant self‐administration of alcohol in rats as well as for high alcohol consumption in Long‐Evans rats and in alcohol preferring [Alko alcohol (AA)] rats was studied here. In the present study, the GHS‐R1A antagonist, JMV2959, was found to reduce the operant self‐administration of alcohol in rats and to decrease high alcohol intake in Long‐Evans rats as well as in AA rats. These results suggest that the ghrelin receptor signaling system, specifically GHS‐R1A, is required for operant self‐administration of alcohol and for high alcohol intake in rats. Therefore, the GHS‐R1A may be a therapeutic target for treatment of addictive behaviors, such as alcohol dependence.
Natural history of chronic hepatitis B REVEALed
Authors: Chen Chien‐Jen , Yang Hwai‐I
Published: February 2011

Chronic hepatitis B is a worldwide public health challenge. Knowledge of natural history of chronic hepatitis B is important for the management of the disease. A community‐based prospective cohort study was carried out to evaluate the risk predictors of progression of chronic hepatitis B in Taiwan. A total of 23 820 participants were enrolled in 1991–1992 from seven townships in Taiwan. Their serum samples were collected at study entry and tested for hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), antibodies against hepatitis C virus (anti‐HCV), alanine aminotransferase (ALT), and α‐fetoprotein (AFP). A subcohort of 3653 male and female participants who were seropositive for HBsAg and seronegative for anti‐HCV was included in the Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer‐Hepatitis B Virus (REVEAL‐HBV) study. Newly developed cases of cirrhosis and hepatocellular carcinoma (HCC) were ascertained through follow‐up examination and data linkage with profiles of the National Cancer Registry, National Health Insurance Database and Death Certification System. The incidence of both HCC and cirrhosis were significantly associated with serum HBV DNA levels in a dose‐response relationship from < 300 (undetectable) to ≥ 1 000 000 copies/mL. The biological gradients remained significant (P < 0.001) after adjustment for age, sex, habits of cigarette smoking and alcohol drinking, HBeAg serostatus, and serum ALT level at cohort entry. A significant association with risk of cirrhosis and HCC was also observed for HBV genotype, precore G1896A mutant and basal core promoter A1762T/G1764A double mutant. Nomograms have been developed for the long‐term risk prediction of cirrhosis and HCC for patients with chronic hepatitis B. Inactive carriers of HBV have an increased HCC incidence and liver‐related mortality than HBsAg‐seronegative controls. Serum HBV DNA level at study entry is a major predictor of spontaneous seroclearance of HBeAg, HBV DNA and HBsAg. These findings may inform the effective and efficient management of chronic hepatitis B.