bluuebunny/crossref_metadata_2025 huggingface dataset:
Mosaic structure of foot-and-mouth disease virus genomes
Authors: Jackson A. L. , O'Neill H. , Maree F. , Blignaut B. , Carrillo C. , Rodriguez L. , Haydon D. T.
Published: January 2007

The results of a simple pairwise-scanning analysis designed to identify inter-serotype recombination fragments, applied to genome data from 156 isolates of Foot-and-mouth disease virus (FMDV) representing all seven serotypes, are reported. Large numbers of candidate recombinant fragments were identified from all parts of the FMDV genome, with the exception of the capsid genes, within which such fragments are infrequent. As expected, intertypic fragment exchange is most common between geographically sympatric FMDV serotypes. After accounting for the likelihood of intertypic convergence in highly conserved parts of the FMDV genome, it is concluded that intertypic recombination is probably widespread throughout the non-structural genes, but that recombination over the 2B/C and 3B/C gene boundaries appears to be less frequent than expected, given the large numbers of recombinant gene fragments arising in these genes.
Population responses to natural and human‐mediated disturbances: assessing the vulnerability of the common hippopotamus (Hippopotamus amphibius)
Authors: Lewison Rebecca
Published: January 2007

Vulnerable wildlife populations can face a suite of anthropogenic activities that may threaten their persistence. However, human‐mediated disturbances are likely to be coincident with natural disturbances that also influence a population. This synergism is often neglected in population projection models. Here I evaluate the effects of natural (rainfall fluctuation) and human disturbances (habitat loss and unregulated hunting) using a multi‐matrix environmental state population model for the common hippopotamus (Hippopotamus amphibius). By evaluating each disturbance type (natural and human) alone and then together, I explicitly consider the importance of incorporating realistic environmental variability into population projection models. The model population was most strongly affected by moderate habitat loss, which yielded the highest probability of crossing the risk thresholds over the 60 year time period, although these probabilities were relatively low (≤0.31). However, the likelihood of crossing the risk thresholds were two to five times as high when human‐mediated and natural disturbances were considered together. When these probabilities were calculated per year of the simulation, the results suggested that even relatively mild human disturbances, when considered in conjunction with realistic natural disturbance, resulted in a high probability (>0.50) of substantial declines within decades. The model highlights the importance of integrating realistic natural disturbances into population models, and suggests that, despite locally abundant populations, protected hippopotamus populations may decline over the next 60 years in response to a combination of environmental fluctuations and human‐mediated threats.
Research Review: In a rush to permanency: preventing adoption disruption
Authors: Coakley Jennifer F. , Berrick Jill D.
Published: January 2007

Since the late 1990s, US, UK and Canadian policy have increasingly focused on improving permanency outcomes for looked‐after children. Although the ideal permanency outcome of reunification is attained for about half of the children entering out‐of‐home care, an increasing number of children are adopted each year. The vast majority of adoptions are stable and secure, but concerns about adoption disruption haunt child welfare workers when making this important permanency decision. Despite a variety of definitions employed in the literature, adoption disruption is a general term used to describe the failure or breakdown of an adoptive child’s placement. Studies dating back to the 1970s have reported adoption disruption rates and the characteristics associated with those involved in such cases. This paper reviews available research, principally from the United States, and offers possible explanations for the wide range of reported disruption rates in the literature. After reviewing the research, practice implications for improving adoption outcomes and suggestions for future research are presented.
Understanding family support provision within the context of prevention: a critical analysis of a local voluntary sector project
Authors: Artaraz Kepa , Thurston Miranda , Davies Sarah
Published: January 2007

This paper presents a model of service process for a family support service at the preventative level as part of a wider debate about child welfare systems in the UK and beyond. The paper places the debate about the shape of preventative family support services within the policy context and uses it to critique various models of service provision, principally the ‘child rescue’ paradigm. From this, the paper explores the characteristics that constitute a complex, yet preventative, family support service. This model is then illustrated using empirical evidence collected from the evaluation of a voluntary and community sector project in the North West of England that describes the service process and some of its characteristics. The paper argues that the model of family support presented has implications for the type of service process that can effectively put the theory into practice. Finally, questions for further research are defined in relation to the implications that this model poses for professional–user relationships and for the professional forms that can deliver preventative family support.
Expression of cytokeratin 20 in urine cytology smears: a potential marker for the detection of urothelial carcinoma
Authors: Bhatia A. , Dey P. , Kumar Y. , Gautam U. , Kakkar N. , Srinivasan R. , Nijhawan R.
Published: January 2007

Background:  Urine cytomorphology is one of the oldest methods for screening and monitoring patients with transitional cell carcinoma (TCC). Sensitivity of urine cytology is relatively low. Ancillary techniques on urine sample may increase the sensitivity.

Aim:  To explore the utility of cytokeratin 20 (CK20) immunostaining in identifying malignant cells in urine cytology smears.

Materials and methods:  Fourteen cases each of confirmed TCC and benign urinary cytology along with five cases of atypical cells in urine were immunostained with a monoclonal CK20 antibody. Of 14 cases of TCC, 12 showed strong positive staining with the antibody. All benign cases were negative except for a few cases in which the umbrella cells were weakly to moderately positive. In all five cases of atypical urine cytology the atypical cells stained positive with the antibody. These cases were later confirmed as TCC on histopathology of bladder wall biopsy.

Conclusion:  CK20 is an important biomarker that can be used to identify TCC in urine cytology smears. It is particularly useful in those cases where malignancy cannot be confirmed by morphology alone.
ReFacto®1 and Advate®2: a single‐dose, randomized, two‐period crossover pharmacokinetics study in subjects with haemophilia A
Authors: DI PAOLA J. , SMITH M. P. , KLAMROTH R. , MANNUCCI P. M. , KOLLMER C. , FEINGOLD J. , KESSLER C. , POLLMANN H. , MORFINI M. , UDATA C. , ROTHSCHILD C. , HERMANS C. , JANCO R.
Published: January 2007

Summary.  ReFacto is a recombinant B‐domain‐deleted, monoclonal antibody‐purified, solvent‐detergent‐treated factor VIII (BDDrFVIII) with no albumin added to the final formulation. Although ReFacto has been shown to be bioequivalent to a plasma‐derived FVIII product (Hemophil‐M) in a randomized, crossover pharmacokinetic (PK) study, the comparability of ReFacto with the full‐length (complete sequence) recombinant FVIII (FLrFVIII, Advate) product has not been previously examined in this manner. The primary objective of this study was to compare the PKs of ReFacto with those of Advate in patients with severe haemophilia A. This was a third‐party unblinded, randomized, multicentre, two‐period crossover PKs study of ReFacto and Advate in subjects with severe haemophilia A (FVIII:C ≤1%). Blood samples were collected over a 48‐h period after i.v. administration of each of the FVIII products. FVIII:C was determined using the chromogenic substrate assay (CSA) in a central laboratory. The plasma FVIII:C PK parameters of ReFacto and Advate were determined using non‐compartmental analysis. Bioequivalence was assessed on maximum plasma concentration (Cmax) and the area under the plasma concentration vs. time curves (AUCs) using an anova. The two products were judged to be equivalent if the 90% confidence limits of the ratio of the geometric mean values of Cmax and AUCs fell within the interval of 80–125%. Results from this PKs comparison of two different rFVIII products, using chromogenic substrate assay to measure FVIII:C, showed that ReFacto and Advate are bioequivalent to each other.
Pathological diagnosis of granulomatous lung disease: a review
Authors: El‐Zammar O A , Katzenstein A‐L A
Published: January 2007

Granulomas in the lung are common diagnostic problems encountered by pathologists. They occur in a wide range of pulmonary conditions, ranging from common entities to uncommon ones and including both infections and non‐infectious diseases. This review summarizes the main histological features that help distinguish various granulomatous lung diseases. It concentrates on the most important and common entities that may be encountered and emphasizes helpful features in the differential diagnosis.
Angiogenesis in preinvasive, early invasive bronchial lesions and micropapillomatosis and correlation with EGFR expression
Authors: Meert A‐P , Feoli F , Martin B , Ninane V , Sculier J‐P
Published: January 2007

Aims:  To study the association between morphological changes of the bronchial epithelium and its angiogenic status evaluated by microvessel count (MVC), in order to gain a better understanding of bronchial carcinogenesis. Also, to correlate MVC with epidermal growth factor receptor (EGFR) expression.

Methods and results:  Eighty‐three biopsy specimens were assessed for MVC: four normal bronchial epithelia, 23 hyperplasias, 26 metaplasias, two mild dysplasias, five moderate dysplasias, nine severe dysplasias, three carcinomas in situ, six early invasive squamous cell carcinomas (EIC) and five cases of micropapillomatosis. We observed a statistically significant difference in terms of MVC between EIC and all other subgroups and between micropapillomatosis and all other subgroups. There was also a statistically significant difference between micropapillomatosis and EIC. We did not observe any difference in MVC between normal mucosa, metaplasias, hyperplasias, dysplasias or carcinoma in situ. EGFR expression was higher in severe dysplasia, carcinoma in situ and EIC, whereas it was very low in micropapillomatosis. A statistically significant difference was observed in the expression profile of EGFR vs. MVC. EGFR expression was increased in severe dysplasia, whereas an increase in MVC occurred only in EIC.

Conclusion:  During bronchial carcinogenesis, except for micropapillomatosis, EGFR expression appears to be a prerequisite for neoangiogenesis in bronchial carcinogenesis.
OLIG2 is a useful immunohistochemical marker in differential diagnosis of clear cell primary CNS neoplasms
Authors: Preusser M , Budka H , Rössler K , Hainfellner J A
Published: January 2007

Aims:  To analyse OLIG2 expression in clear cell primary central nervous system (CNS) tumours to clarify the diagnostic usefulness of OLIG2 immunohistochemistry in this subset of brain tumours.

Methods and results:  We analysed OLIG2 expression in 60 oligodendroglial neoplasms (57 with and three without chromosome 1p aberration), 10 central neurocytomas, 10 clear cell ependymomas, nine dysembryoplastic neuroepithelial tumours (DNTs) and two clear cell meningiomas using immunohistochemistry. Additionally, we analysed oligodendroglial neoplasms with numerous gliofibrillary and minigemistocytic oligodendrocytes for OLIG2/glial fibrillary acidic protein (GFAP) coexpression and central neurocytoma for coexpression of neurone‐specific nuclear protein (NeuN) and OLIG2 using double immunofluorescent labelling and confocal laser scanning microscopy. All oligodendroglial neoplasms and DNTs showed widespread OLIG2 expression. Eight of 10 central neurocytomas, all clear cell meningiomas and 8/10 clear cell ependymomas were negative for OLIG2. Two of 10 central neurocytomas and 2/10 clear cell ependymomas showed focal OLIG2 expression. We found prominent coexpression of GFAP and OLIG2 in gliofibrillary and minigemistocytic oligodendrocytes. Further, we found coexpression of NeuN and OLIG2 in single cells in central neurocytoma.

Conclusions:  Widespread OLIG2 expression discriminates oligodendroglial neoplasms or DNTs from other clear cell primary brain tumour types. In clear cell primary brain tumours lacking OLIG2 expression, differential diagnosis may require additional immunohistochemical markers.
The clinicopathological and prognostic significance of membrane type 1 matrix metalloproteinase (MT1‐MMP) and MMP‐9 according to their localization in invasive breast carcinoma
Authors: Mylona E , Nomikos A , Magkou C , Kamberou M , Papassideri I , Keramopoulos A , Nakopoulou L
Published: January 2007

Aims:  To investigate the clinicopathological and prognostic significance of membrane type 1 matrix metalloproteinase (MT1‐MMP) and MMP‐9 proteins expression in invasive breast carcinoma and their relationship to tumour proliferation and expression of c‐erbB2 and peroxisome proliferator‐activated receptor (PPAR) gamma.

Methods:  Immunohistochemistry was carried out on 175 paraffin‐embedded breast tissue specimens to detect MT1‐MMP, MMP‐9, oestrogen receptor (ER), progesterone receptor, c‐erbB‐2, Ki67, topoisomerase IIα (topo IIα) and PPARγ protein expression.

Results:  Both MT1‐MMP and MMP‐9 were expressed in the cytoplasm of the malignant cells and the peritumoral stroma. Cytoplasmic MT1‐MMP was more often observed in ER+ tumours (P = 0.022), of a lower nuclear grade (P = 0.020) and with reduced expression of Ki67 and topo IIα (P = 0.027 and P = 0.006, respectively). Moreover, cytoplasmic MT1‐MMP was positively associated with MMP‐9 (P = 0.010) and PPARγ (P < 0.0001). Cytoplasmic MMP‐9 was inversely associated with Ki67 (P = 0.034) and topo IIα (P = 0.004), whereas its relationship with MT1‐MMP (P = 0.034) and PPARγ (P = 0.024) was found to be positive. Stromal MMP‐9 was more often observed in c‐erbB2+ tumours (P = 0.043) and had an unfavourable impact on overall and relapse‐free survival in both univariate (P = 0.0157 and P = 0.0274, respectively) and multivariate analyses (P = 0.007 and P = 0.024, respectively).

Conclusions:  Cytoplasmic MT1‐MMP and MMP‐9 seem to be related to well‐differentiated tumours, with a low proliferation potential, while stromal MMP‐9 is associated with an aggressive tumour phenotype and is recognized as an independent poor prognostic indicator.
The Aedes albopictus inhibitor of apoptosis 1 gene protects vertebrate cells from bluetongue virus‐induced apoptosis
Authors: Li Q. , Li H. , Blitvich B. J. , Zhang J.
Published: January 2007

We sequenced and characterized the inhibitor of apoptosis (iap) 1 gene from Aedes albopictus, designated as Aaiap1. The Aaiap1 gene rescued Spodoptera frugiperda (Sf9) cells from apoptosis when cotransfected with the Drosophila pro‐apoptotic hid gene. The antiapoptotic function of the Aaiap1 gene was evaluated in the bluetongue virus (BTV)‐induced apoptosis system. BTV infection induced apoptosis in vertebrate cells via the intrinsic apoptotic pathway. This was shown by the translocation of cytochrome C and the second mitochondria‐derived activator of caspase (Smac, also known as DIABLO) from the mitochondria and the subsequent activation of caspase‐9 and ‐3. Stable expression of the Aaiap1 gene in derivative baby hamster kidney cells delayed BTV‐induced apoptosis by 24 h and reduced the BTV progeny yield by 10‐fold. This study provides the first evidence that the mosquito AaIAP1 protein possesses antiapoptotic activity.
Social organization and movement influence the incidence of bovine tuberculosis in an undisturbed high‐density badgerMeles melespopulation
Authors: VICENTE J. , DELAHAY R. J. , WALKER N. J. , CHEESEMAN C. L.
Published: January 2007

The culling of European badgersMeles meleshas been a central part of attempts to control bovine tuberculosis (TB) in British cattle for many years. Recent results, however, indicate that this approach could in practice enhance disease spread.

This paper looks at the relationship between TB incidence and badger ecology in a high‐density population in south‐west England, which has been the subject of a long‐term intensive study. The principal aims were to relate the probability of TB incidence, as detected by culture of clinical samples (i.e. excretion of bacilli), at the level of the individual and of the social group to demographic processes, movement, social organization and disease dynamics.

The probability of an individual being an incident case was greater in groups where TB was already present, although this was less influential in groups that were subject to some instability in numbers. Both individuals and groups were more likely to be incident cases where the social group was diminishing in size, although no relationship was observed with group size itself. This suggests that the process of group size reduction rather than group sizeper sehas most influence on disease dynamics. The likelihood that either an individual or a group was an incident case was positively correlated with both individual and group‐level movement. When the proportion of females in a social group was high, the positive association between movement and incidence was found to be more pronounced and there was a significantly higher probability of incident cases among males.

These relationships highlight the importance of social structure in driving TB transmission dynamics in this stable, high‐density badger population. The results support the idea that a stable social structure mitigates against new incident cases of disease, and are consistent with the contention that badger culling may create the social circumstances for enhanced transmission of TB.
Are large‐scale distributional shifts of the blue‐winged macaw (Primolius maracana) related to climate change?
Authors: Nunes Maria Flávia Conti , Galetti Mauro , Marsden Stuart , Pereira Ricardo Scachetti , Townsend Peterson A.
Published: January 2007

Aim To evaluate whether observed geographical shifts in the distribution of the blue‐winged macaw (Primolius maracana) are related to ongoing processes of global climate change. This species is vulnerable to extinction and has shown striking range retractions in recent decades, withdrawing broadly from southern portions of its historical distribution. Its range reduction has generally been attributed to the effects of habitat loss; however, as this species has also disappeared from large forested areas, consideration of other factors that may act in concert is merited.

Location Historical distribution of the blue‐winged macaw in Brazil, eastern Paraguay and northern Argentina.

Methods We used a correlative approach to test a hypothesis of causation of observed shifts by reduction of habitable areas mediated by climate change. We developed models of the ecological niche requirements of the blue‐winged macaw, based on point‐occurrence data and climate scenarios for pre‐1950 and post‐1950 periods, and tested model predictivity for anticipating geographical distributions within time periods. Then we projected each model to the other time period and compared distributions predicted under both climate scenarios to assess shifts of habitable areas across decades and to evaluate an explanation for observed range retractions.

Results Differences between predicted distributions of the blue‐winged macaw over the twentieth century were, in general, minor and no change in suitability of landscapes was predicted across large areas of the species’ original range in different time periods. No tendency towards range retraction in the south was predicted, rather conditions in the southern part of the species’ range tended to show improvement for the species.

Main conclusions Our test permitted elimination of climate change as a likely explanation for the observed shifts in the distribution of the blue‐winged macaw, and points rather to other causal explanations (e.g. changing regional land use, emerging diseases).
Association between aortic calcification and total and cardiovascular mortality in older women
Authors: Rodondi N. , Taylor B. C. , Bauer D. C. , Lui L.‐Y. , Vogt M. T. , Fink H. A. , Browner W. S. , Cummings S. R. , Ensrud K. E.
Published: January 2007

Objectives.  To determine whether older women with abdominal aortic calcification had a greater cardiovascular and all‐cause mortality, as such data are limited in older adults.

Design.  Prospective cohort study with a mean follow‐up of 13 years

Setting.  Community‐based sample with four US clinical centres.

Subjects.  A total of 2056 women aged ≥65 years with abdominal aortic calcification assessed on baseline radiographs.

Main outcome measure.  Mortality rate (all, cardiovascular, cancer or other cause) adjudicated from death certificates and hospital records.

Results.  The prevalence of abdominal aortic calcification increased with age, ranging from 60% at age 65–69 years to 96% at 85 years and older. Participants with aortic calcification were more likely to die during follow‐up of any cause (47% vs. 27%) or a cardiovascular‐specific cause (18% vs. 11%, both P < 0.001) than those without aortic calcification. In age‐adjusted analyses, aortic calcification was associated with a greater rate of all‐cause and cause‐specific mortality (cardiovascular, cancer, and other, all P ≤ 0.01). In analyses adjusted for age and cardiovascular risk factors, aortic calcification was associated with an increased rate of all‐cause mortality (HR: 1.37, 95% CI: 1.15–1.64), and noncardiovascular noncancer mortality (HR: 1.57, 95% CI: 1.17–2.11). The associations between aortic calcification and cancer mortality (HR: 1.44, 95% CI: 1.00–2.08) or cardiovascular mortality (HR: 1.18, 95% CI: 0.88–1.57) showed a similar pattern without reaching statistical significance, but was slightly stronger for mortality from coronary heart disease (HR: 1.53, 95% CI: 0.91–2.56).

Conclusions.  Abdominal aortic calcification in older women is associated with increased mortality. Future research should examine potential mechanisms for this association.
Population structure of Hypochaeris salzmanniana DC. (Asteraceae), an endemic species to the Atlantic coast on both sides of the Strait of Gibraltar, in relation to Quaternary sea level changes
Authors: ORTIZ M. Á. , TREMETSBERGER K. , TALAVERA S. , STUESSY T. , GARCÍA‐CASTAÑO J. L.
Published: January 2007

To detect potential Pleistocene refugia and colonization routes along the Atlantic coast, we analysed amplified fragment length polymorphisms (AFLPs) in 140 individuals from 14 populations of Hypochaeris salzmanniana (Asteraceae), an annual species endemic to the southwestern European and northwestern African coastal areas. Samples covered the total distributional range of the species, with eight populations in southwestern Spain and six populations in northwestern Morocco. Using nine primer combinations, we obtained 546 fragments in H. salzmanniana and its sister species H. arachnoidea of which 487 (89.2%) were polymorphic. The neighbour‐joining tree shows that the populations south of the Loukos river in Morocco are clearly differentiated, having more polymorphic, private, and rare fragments, and higher genetic diversity, than all the other populations. The southernmost populations in Morocco, south of the river Sebou, form a large panmictic population. They are probably the oldest populations that have been relatively unaffected by stochastic processes resulting from Pleistocene glaciations. Northward migration of populations during this period may have resulted in loss of genetic diversity in specific regions, perhaps due to bottlenecks caused by rise in sea level during interglacial periods, and, in some cases, by changes in the breeding system.
Comparative phylogeography of three endemic rodents from the Albertine Rift, east central Africa
Authors: HUHNDORF MICHAEL H. , KERBIS PETERHANS JULIAN C. , LOEW SABINE S.
Published: January 2007

The major aim of this study was to compare the phylogeographic patterns of codistributed rodents from the fragmented montane rainforests of the Albertine Rift region of east central Africa. We sampled individuals of three endemic rodent species, Hylomyscus denniae, Hybomys lunaris and Lophuromys woosnami from four localities in the Albertine Rift. We analysed mitochondrial DNA sequence variation from fragments of the cytochrome b and control region genes and found significant phylogeographic structuring for the three taxa examined. The recovered phylogenies suggest that climatic fluctuations and volcanic activity of the Virunga Volcanoes chain have caused the fragmentation of rainforest habitat during the past 2 million years. This fragmentation has played a major role in the diversification of the montane endemic rodents of the region. Estimation of the divergence times within each species suggests a separation of the major clades occurring during the mid to late Pleistocene.
Differential gene expression between adult queens and workers in the antLasius niger
Authors: GRÄFF JOHANNES , JEMIELITY STEPHANIE , PARKER JOEL D. , PARKER KAREN M. , KELLER LAURENT
Published: January 2007

Ants and other social insects forming large societies are generally characterized by marked reproductive division of labour. Queens largely monopolize reproduction whereas workers have little reproductive potential. In addition, some social insect species show tremendous lifespan differences between the queen and worker caste. Remarkably, queens and workers are usually genotypically identical, meaning that any phenotypic differences between the two castes arise from caste‐specific gene expression. Using a combination of differential display, microarrays and reverse Northern blots, we found 16 genes that were differentially expressed between adult queens and workers in the antLasius niger, a species with highly pronounced reproductive division of labour and a several‐fold lifespan difference between queens and workers. RNA ligase mediated rapid amplification of cDNA ends (RLM‐RACE) and gene walking were used to further characterize these genes. On the basis of the molecular function of their nearest homologues, three genes appear to be involved in reproductive division of labour. Another three genes, which were exclusively overexpressed in queens, are possibly involved in the maintenance and repair of the soma, a candidate mechanism for lifespan determination. In‐depth functional analyses of these genes are now needed to reveal their exact role.
Radio sources in the 6dFGS: local luminosity functions at 1.4 GHz for star-forming galaxies and radio-loud AGN
Authors: Mauch Tom , Sadler Elaine M.
Published: January 2007

We have identified 7824 radio sources from the 1.4 GHz NRAO VLA Sky Survey (NVSS) with galaxies brighter than K= 12.75 mag in the Second Incremental Data Release of the 6 degree Field Galaxy Survey (6dFGS DR2). The resulting sample of redshifts and optical spectra for radio sources over an effective sky area of 7076 deg2 (about 17 per cent of the celestial sphere) is the largest of its kind ever obtained. NVSS radio sources associated with galaxies in the 6dFGS span a redshift range 0.003 < z < 0.3 and have median . Through visual examination of 6dF spectra we have identified the dominant mechanism for radio emission from each galaxy. 60 per cent are fuelled by star formation and 40 per cent are fuelled by an active galactic nucleus (AGN) powered by a supermassive black hole. We have accurately determined the local radio luminosity function (RLF) at 1.4 GHz for both classes of radio source and have found it to agree well with other recent determinations. From the RLF of star-forming galaxies we derive a local star formation density of 0.022 ± 0.001 M⊙ yr−1 Mpc−3, in broad agreement with recent determinations at radio and other wavelengths.

We have split the RLF of radio-loud AGNs into bins of absolute K-band magnitude (MK) and compared this with the underlying K-band galaxy luminosity function of all 6dFGS galaxies to determine the bivariate radio-K-band luminosity function. We verify that radio-loud AGNs preferentially inhabit the brightest and hence most massive host galaxies and show that the fraction of all galaxies which host a radio-loud AGN scales as fradio-loud∝L2.1K for fradio-loud < 0.3, indicative of a similarly strong scaling with black hole mass and stellar mass.
Colonization of tree xylem by Phytophthora ramorum, P. kernoviae and other Phytophthora species
Authors: Brown A. V. , Brasier C. M.
Published: January 2007

The aetiology and frequency of Phytophthora spp. in discoloured xylem tissue beneath phloem lesions was investigated in a range of broadleaved trees infected with P. ramorum, P. kernoviae, P. cambivora, P. citricola and other species. Isolation was attempted from the inner surface of 81 sterilized discoloured wood panels (6 × 4 cm) from 53 trees. Discolouration mostly extended 1–5 mm into the xylem (75%), but incursions of 6–10 mm (10%) and 10–25 mm (15%) were frequent. Of the wood panels, 81% yielded Phytophthora spp. In 66 cases, both a wood panel and an overlying phloem panel were sampled. In 56% of these, a Phytophthora sp. was isolated from both the wood and the phloem panel. In 23% the Phytophthora sp. was isolated from the wood panel only and in 8% from the phloem panel only. Small ‘island’ phloem lesions, often in linear arrays adjacent to main lesions, were a common feature of Fagus sylvatica and Quercus spp. trees infected with P. ramorum or P. kernoviae. Island lesions were often connected by underlying strips or intermittent pits of discoloured xylem in line with the wood grain. Phytophthora ramorum, P. kernoviae and other Phytophthora spp. were successfully isolated from these connecting xylem features with P. ramorum and P. kernoviae also recovered from discoloured tissue 5–25 mm below exposed xylem surfaces 24–27 months after the overlying phloem was removed. These results show that these pathogens commonly occupy xylem beneath phloem lesions; that they can perennate in xylem tissue; that they can spread in xylem tissue ahead of phloem lesions; and indicate that they may initiate new phloem lesions in this way. Such colonization must lead to at least local xylem dysfunction. It is recommended that, if xylem discoloration is present, isolation of the Phytophthora sp. should be attempted from the xylem as well as the bark; also, that removal of infected outer sapwood should be undertaken during excision of bleeding lesions for disease control and in protocols aimed at preventing national or international spread of these tree stem pathogens.
Two weather‐based models for predicting the onset of seasonal release of ascospores of Leptosphaeria maculans or L. biglobosa
Authors: Salam M. U. , Fitt B. D. L. , Aubertot J. ‐N. , Diggle A. J. , Huang Y. J. , Barbetti M. J. , Gladders P. , Jȩdryczka M. , Khangura R. K. , Wratten N. , Fernando W. G. D. , Penaud A. , Pinochet X. , Sivasithamparam K.
Published: January 2007

Weather‐based models (Improved Blackleg Sporacle and SporacleEzy) to predict the date of onset of seasonal release from oilseed rape debris of ascospores of Leptosphaeria maculans or L. biglobosa, causes of phoma stem canker, were developed and tested with data from diverse environments in Australia, Canada, France, Poland and the UK. Parameters were estimated, using the same datasets from experiments in the UK and Poland, with an accuracy of root mean squared deviation (RMSD) of 7·4 (with a bias of −4·54, L. maculans) and 8·5 (with a bias of 0·30, L. biglobosa) days for Improved Blackleg Sporacle, and of 2·9 (with a bias of −0·06, L. maculans) and 7·3 (with a bias of −1·18, L. biglobosa) days for SporacleEzy. When tested with data independent of those used for parameter estimation, overall predictions agreed well with observed data in five countries, both for Improved Blackleg Sporacle (R2 = 0·96, slope = 1·00, standard error = 0·03, P > 0·05, n = 46) and SporacleEzy (R2 = 0·96, slope = 0·98, standard error = 0·03, P > 0·05, n = 46). However, SporacleEzy performed better in Australia, Canada, Poland and the UK (RMSD = 10·6, 9·7, 5·4 and 3·4 days, respectively) than Improved Blackleg Sporacle (RMSD = 11·7, 11·0, 5·6 and 6·5 days, respectively). In contrast, the prediction from Improved Blackleg Sporacle (RMSD = 8·0 days) was better in France than that from SporacleEzy (RMSD = 15·9 days). Sensitivity analysis showed that better parameter estimation could improve the quality of prediction of SporacleEzy (RMSD = 7·6 days) under French conditions. These models are capable of estimating the first seasonal release of ascospores of organisms causing phoma stem canker on oilseed rape under many climates and thus could contribute to development of strategies for control of the disease.
Function of phytochelatin synthase in catabolism of glutathione‐conjugates
Authors: Blum Ralph , Beck Andreas , Korte Arthur , Stengel Anna , Letzel Thomas , Lendzian Klaus , Grill Erwin
Published: January 2007

Detoxification of xenobiotic compounds and heavy metals is a pivotal capacity of organisms, in which glutathione (GSH) plays an important role. In plants, electrophilic herbicides are conjugated to the thiol group of GSH, and heavy metal ions form complexes as thiolates with GSH‐derived phytochelatins (PCs). In both detoxification processes of plants, phytochelatin synthase (PCS) emerges as a key player. The enzyme is activated by heavy metal ions and catalyzes PC formation from GSH by transferring glutamylcysteinyl residues (γ‐EC) onto GSH. In this study with Arabidopsis, we show that PCS plays a role in the plant‐specific catabolism of glutathione conjugates (GS‐conjugates). In contrast to animals, breakdown of GS‐conjugates in plants can be initiated by cleavage of the carboxyterminal glycine residue that leads to the generation of the correspondingγ‐EC‐conjugate. We used the xenobiotic bimane in order to follow GS‐conjugate turnover. Functional knockout of the two PCS of Arabidopsis, AtPCS1 and AtPCS2, revealed that AtPCS1 provides a major activity responsible for conversion of the fluorescent bimane‐GS‐conjugate (GS‐bimane) intoγ‐EC‐bimane. AtPCS1 deficiency resulted in aγ‐EC‐bimane deficiency. Transfection of PCS‐deficient cells withAtPCS1recoveredγ‐EC‐bimane levels. The level of theγ‐EC‐bimane conjugate was enhanced several‐fold in the presence of Cd2+ions in the wild type, but not in the PCS‐deficient double mutant, consistent with a PCS‐catalyzed GS‐conjugate turnover. Thus AtPCS1 has two cellular functions: mediating both heavy metal tolerance and GS‐conjugate degradation.
Non‐random distribution of T‐DNA insertions at various levels of the genome hierarchy as revealed by analyzing 13 804 T‐DNA flanking sequences from an enhancer‐trap mutant library
Authors: Zhang Jian , Guo Dong , Chang Yuxiao , You Changjun , Li Xingwang , Dai Xiaoxia , Weng Qijun , Zhang Jianwei , Chen Guoxing , Li Xianghua , Liu Huifang , Han Bin , Zhang Qifa , Wu Changyin
Published: January 2007

We isolated 13 804 T‐DNA flanking sequence tags (FSTs) from a T‐DNA insertion library of rice. A comprehensive analysis of the 13 804 FSTs revealed a number of features demonstrating a highly non‐random distribution of the T‐DNA insertions in the rice genome: T‐DNA insertions were biased towards large chromosomes, not only in the absolute number of insertions but also in the relative density; within chromosomes the insertions occurred more densely in the distal ends, and less densely in the centromeric regions; the distribution of the T‐DNA insertions was highly correlated with that of full‐length cDNAs, but the correlations were highly heterogeneous among the chromosomes; T‐DNA insertions strongly disfavored transposable element (TE)‐related sequences, but favored genic sequences with a strong bias toward the 5′ upstream and 3′ downstream regions of the genes; T‐DNA insertions preferentially occurred among the various classes of functional genes, such that the numbers of insertions were in excess in certain functional categories but were deficient in other categories. The analysis of DNA sequence compositions around the T‐DNA insertion sites also revealed several prominent features, including an elevated bendability from −200 to 200 bp relative to the insertion sites, an inverse relationship between the GC and TA skews, and reversed GC and TA skews in sequences upstream and downstream of the insertion sites, with both GC and TA skews equal to zero at the insertion sites. It was estimated that 365 380 insertions are needed to saturate the genome with P = 0.95, and that the 45 441 FSTs that have been isolated so far by various groups tagged 14 287 of the 42 653 non‐TE related genes.
The mitogen‐activated protein kinases WIPK and SIPK regulate the levels of jasmonic and salicylic acids in wounded tobacco plants
Authors: Seo Shigemi , Katou Shinpei , Seto Hideharu , Gomi Kenji , Ohashi Yuko
Published: January 2007

In tobacco (Nicotiana tabacum), wounding causes rapid activation of two mitogen‐activated protein kinases (MAPKs), wound‐induced protein kinase (WIPK) and salicylic acid (SA)‐induced protein kinase (SIPK), and the subsequent accumulation of jasmonic acid (JA). Our previous studies suggested that activation of WIPK is required for the production of wound‐induced JA. However, the exact role of WIPK remains unresolved. We generated transgenic tobacco plants in which eitherWIPKorSIPKwere silenced using RNA interference to define the roles of WIPK and SIPK in the wound response. In addition, transgenic tobacco plants were generated in which bothWIPKandSIPKwere silenced to examine the possibility that they have redundant roles. Wound‐induced JA production was reduced compared with non‐silenced plants in all of theWIPK‐,SIPK‐ andWIPK/SIPK‐silenced plants. Transgenic plants over‐expressingNtMKP1, a gene encoding tobacco MAPK phosphatase, which inactivates WIPK and SIPK, also exhibited reduced JA production in response to wounding. In bothWIPK/SIPK‐silenced andNtMKP1‐over‐expressing plants, wounding resulted in an abnormal accumulation of both SA and transcripts for SA‐responsive genes. These results suggest that WIPK and SIPK play an important role in JA production in response to wounding, and that they function cooperatively to control SA biosynthesis.
EFFICACY OFSARGASSUM POLYCYSTUM(PHAEOPHYCEAE) SULPHATED POLYSACCHARIDE AGAINST PARACETAMOL‐INDUCED DNA FRAGMENTATION AND MODULATION OF MEMBRANE‐BOUND PHOSPHATASES DURING TOXIC HEPATITIS
Authors: Raghavendran HB , Sathivel A , Yogeeta RSSK , Devaki T
Published: January 2007

The aim of the present study was to assess the protective effect ofSargassum polycystum(sulphated polysaccharide) extract against paracetamol‐induced DNA strand breaks and modulation of membrane‐bound phosphatases, protein thiols and inorganic cations during toxic hepatitis.

Seaweed extract (200 mg/kg per day for 21 days) was administered to male Wistar rats against paracetamol challenge. Serum and liver tissues were used to assess levels of ATPase, protein thiols and inorganic cations using atomic absorption spectroscopy. The fragmentation of DNA was assessed by agarose gel electrophoresis.

Paracetamol induced intracellular stress, accompanied by changes in the structural and functional characteristics of liver cell membranes, which affected DNA integrity, membrane‐bound ATPase and inorganic cations homeostasis. Rats intoxicated with paracetamol (800 mg/kg, i.p.) showed significant impairment in activities of total ATPase, Mg2+‐ATPase, Ca+‐ATPase and Na+/K+‐ATPase, with concomitant changes in the levels of tissue protein thiols and inorganic cations, such as Na+, K+and Ca2+. These changes were prevented in animals pretreated withS. polycystumextract, which indicates thatS. polycystumsupplementation could exert some protective effect against paracetamol‐induced toxic hepatitis in rats.

The protective effect of the seaweed extract may be due to the presence of sulphated compounds that have free radical‐scavenging activity.
NEUROPROTECTIVE EFFECTS OF DAURICINE AGAINST APOPTOSIS INDUCED BY TRANSIENT FOCAL CEREBRAL ISCHAEMIA IN RATS VIA A MITOCHONDRIAL PATHWAY
Authors: Li Yan‐Hong , Gong Pei‐Li
Published: January 2007

Previous experimental studies have shown that dauricine can protect the brain against ischaemic damage, but the underlying mechanisms remain unknown. In the present study, we examined whether dauricine inhibits neuronal apoptosis in the penumbra in a rat model of transient focal cerebral ischaemia.

Male Wistar rats underwent a 90 min temporary occlusion of the middle cerebral artery. Dauricine (21, 42 and 84 mg/kg) was administered by intragastric gavage twice a day for 3 days before ischaemia. Rats were killed and brain samples were collected 24 h after ischaemia. Histopathological outcome was evaluated by haematoxylin–eosin staining. Apoptotic changes were evaluated by terminal deoxyribonucleotidyl transferase‐mediated dUTP–digoxigenin nick end‐labelling (TUNEL) for DNA fragmentation. The mitochondrial pathway was explored using immunohistochemistry for cytochrome c release, caspase 9 and caspase 3 activation, as well as by reverse transcription–polymerase chain reaction for determination of caspase 9 and caspase 3 mRNA expression.

Cytochrome c release, activation of caspase 9 and caspase 3 and DNA fragmentation were detected 24 h after ischaemia. Dauricine (42 and 84 mg/kg) pretreatment improved histopathological recovery, diminished DNA fragmentation and reduced cytochrome c release and activation of caspase 9 and caspase 3 in the penumbra at 24 h.

These findings suggest that dauricine attenuates apoptosis in the penumbra after transient focal cerebral ischaemia. The infarct‐reducing effects of dauricine may be due, in part, to the inhibition of apoptotic cell death via a mitochondrial pathway in the penumbra.
DIFFERENTIAL DEVELOPMENT OF CARBACHOL‐INDUCED DESENSITIZATION IN RECEPTOR‐MEDIATED Ca2+ INFLUX AND Ca2+ RELEASE PATHWAYS IN SMOOTH MUSCLE OF GUINEA‐PIG TAENIA CAECI
Authors: Hishinuma Shigeru , Matsumoto Yukio , Sato Ryo , Saito Masaki
Published: January 2007

We have found that development of carbachol (CCh)‐induced desensitization to receptor agonists, but not to receptor by‐passed stimulation, is transiently interrupted by a Ca2+‐dependent resensitization during the early stage in the smooth muscle of guinea‐pig taenia caeci. To further characterize the receptor‐mediated signal transduction pathways involved in this peculiar desensitization process, we examined the desensitization processes during Ca2+ influx‐ and Ca2+ release‐mediated contractions in response to activation of muscarinic receptors or histamine H1 receptors.

Desensitization treatment with 10−4 mol/L CCh for 30 min in the presence of extracellular Ca2+ resulted in desensitization to the muscarinic agonists McN‐A‐343 or AHR‐602, which are known to induce contraction only in the presence of extracellular Ca2+ in taenia caeci. The development of desensitization to these agonists was interrupted by a transient resensitization at 1 min. In contrast, the transient resensitization phase was lost following removal of extracellular Ca2+ during the desensitization treatment with CCh; under these conditions, the desensitization developed gradually without an apparent resensitization phase.

Contractions to 10−4 mol/L CCh and 10−4 mol/L histamine in the absence of extracellular Ca2+ were gradually desensitized without a resensitization phase following the CCh desensitization treatment, irrespective of the presence or absence of extracellular Ca2+ during CCh treatment, although the onset of the desensitization was delayed under Ca2+‐free conditions.

These results suggest that the receptor‐mediated Ca2+ influx and Ca2+ release pathways are differentially desensitized to CCh and that the transient resensitization appears to regulate the desensitization process in response to Ca2+ influx‐mediated contraction. Such differential processes of desensitization in receptor‐mediated bifurcated signalling pathways may determine cellular responsiveness to certain types of stimuli, depending on the different Ca2+ sources required for contraction.
ROLE OF DORSAL HIPPOCAMPAL CANNABINOID RECEPTORS AND NITRIC OXIDE IN ANXIETY LIKE BEHAVIOURS IN RATS USING THE ELEVATED PLUS‐MAZE TEST
Authors: Roohbakhsh Ali , Moghaddam Akbar Hajizadeh , Massoudi Roohollah , Zarrindast Mohammad‐Reza
Published: January 2007

The important role of the cannabinoid system in the modulation of anxiety like behaviours in clinical and experimental studies has been proposed. However, investigations into this effect of cannabinoids has produced contradictory results. It has been reported that different neurotransmitters, such as nitric oxide (NO), are involved in the behavioural effects of cannabinoids. The hippocampus is also an important brain region in the modulation of anxiety in which CB1 receptors are densely expressed. The present study was designed to evaluate the interactions between cannabinoid and NO systems in the CA1 brain region of the rats using the plus‐maze test.

Rats were anaesthetized with ketamine and xylazine and special cannulas were inserted stereotaxically into the CA1 region of the dorsal hippocampus. After 1 week recovery, the effects of intra‐CA1 administration of WIN55212‐2 (1, 2.5 and 5 µg/rat), AM251 (2, 10 and 50 ng/rat), l‐arginine (0.01, 0.1 and 1 µg/rat) and NG‐nitro‐l‐arginine methyl ester (l‐NAME; 1, 10 and 100 ng/rat) on percentage open arm time (%OAT) and percentage open arm entries (%OAE) were determined. Moreover, the effects of pretreatment with AM251 (2 ng/rat), l‐arginine (0.01 µg/rat) and l‐NAME (1 ng/rat) on the response induced by intra‐CA1 administration of WIN55212‐2 were also assessed.

The administration of either l‐arginine or l‐NAME into the CA1 region produced significant anxiogenic‐like responses, whereas administration of AM251 induced anxiolytic effects. Intra‐CA1 injection of WIN55212‐2 produced a significant anxiogenic‐like effect that was reversed by AM251 and was also altered by l‐NAME, but not by l‐arginine.

These data imply that cannabinoids may have anxiogenic‐like effects in the CA1 region of the hippocampus in which CB1 receptors and NO may be involved.