bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seed mass and seed nutrient content as predictors of seed output variation between species
Authors: Henery Martin L. , Westoby Mark 
Published: December 2004

In patch‐occupancy models for vegetation, propagule output per area occupied is a key species trait, influencing the potential to colonize vacant patches, and hence species dynamics and coexistence. We estimated seed output across a range of species and quantified its relationship to seed dry mass, seed N and P content, and accessory costs in fruiting structures. Fruiting and seed production data were obtained for 47 woody perennial species, spanning an almost 3000‐fold range of seed mass, over a period of one year in Ku‐ring‐gai Chase National Park, New South Wales, Australia. Seed output was measured as numbers per m2 canopy outline and per m2 leaf area.
Of cross‐species variation in seed output per m2 canopy outline per year, 72% could be predicted from seed mass alone, with a directly inverse relationship (log‐log slope not significantly different from −1). Seed output per m2 leaf area could be predicted somewhat more tightly (75%), indicating leaf area per canopy outline area accounted for some cross‐species variation. Reproductive production per m2 occupied per year varied much less than seed mass and accounted for the remaining variation in seed output. Although accessory costs were about equal in magnitude to seed mass as a component of aggregate investment per seed, they were strongly correlated with seed mass, and consequently did not add substantially to the predictive power.
Total mass of N or P per seed were found to be slightly but significantly better predictors of seed output variation than dry seed mass (83% and 78%, respectively). This supports the idea that mineral nutrients are a more fundamental currency for seed production than dry mass. Seed mass, whether measured as dry mass or as N or P, appears to be the principal driver of variation in seed output per m2 occupied, and consequently is among the most important dimensions of ecological variation across coexisting species.
Immunohistochemical detection of amelogenin and cytokeratin 19 in epithelial odontogenic tumors
Authors: Kumamoto H , Yoshida M , Ooya K 
Published: December 2004

OBJECTIVE: Epithelial odontogenic tumors exhibit considerable histological variation and are classified into several benign and malignant entities. Expression of amelogenin and cytokeratin 19 (CK19), that are potentially useful polypeptides for identification of odontogenic epithelial components, was evaluated in various types of epithelial odontogenic tumors.MATERIALS AND METHODS: Specimens of 33 ameloblastomas, three calcifying epithelial odontogenic tumors (CEOTs), two clear cell odontogenic tumors (CCOTs) and five malignant ameloblastomas were examined by immunohistochemistry using anti‐amelogenin and anti‐CK19 antibodies.RESULTS: Immunohistochemical reactivity for amelogenin was detected in many peripheral columnar or cuboidal cells and some central polyhedral cells in ameloblastomas, and histological variants showed various degrees of amelogenin expression. Expression of CK19 was diffusely present in neoplastic cells in ameloblastomas, and decreased expression was found in keratinizing cells of acanthomatous variants and some neoplastic cells of desmoplastic variants. In CEOTs, immunohistochemical reactivity for amelogenin was detected in neoplastic cells and intercellular amyloid‐like materials, whereas CK19 was expressed in neoplastic cells. CCOTs showed positive reactivity for amelogenin and CK19 in neoplastic cells. Malignant ameloblastomas exhibited various degrees of amelogenin expression with constant CK19 expression in neoplastic cells.CONCLUSION: Diverse types of epithelial odontogenic tumors express amelogenin and CK19, suggesting that these tumors have ameloblastic differentiation or odontogenic epithelial properties.
Maryland dental hygienists' knowledge and opinions of oral cancer risk factors and diagnostic procedures
Authors: Syme SE , Drury TF , Horowitz AM 
Published: December 2004

OBJECTIVES: To examine Maryland dental hygienists' (DHs) knowledge of oral cancer risk factors and diagnostic procedures, as well as opinions about the currency and adequacy of their oral cancer knowledge, educational preparation, interest in, and preferred types of, continuing education courses.METHODS: Seven hundred DHs were randomly selected from a registry of 2677 Maryland licensed dental hygienists. A mailed survey instrument provided baseline data on 331 (RR = 60%) DHs. Stratified tabular and logistic analytical techniques were employed (alpha level ≤0.05).RESULTS: Most correctly identified tobacco use (99.7%) and alcohol use (89%) as risk factors; however, 31% incorrectly identified poor oral hygiene as a risk factor. 64% of DHs correctly identified older age as a risk factor, yet only 16% identified that the majority of oral cancers are diagnosed in the 60+ year old age group. Nearly 91% correctly identified the examination procedures of the tongue for oral cancer detection; while only 16% of DHs correctly identified erythroplakia and leukoplakia as the conditions most likely associated with oral cancer.CONCLUSIONS: Gaps in knowledge exist and strongly suggest the need for continuing education courses to clarify risk factors and diagnostic procedures associated with earlier oral cancer detection and prevention.
Apoptosis of biliary epithelial cells in primary biliary cirrhosis and primary sclerosing cholangitis
Authors: Tinmouth Jill , Lee Mary , Wanless Ian R. , Tsui Florence W. L. , Inman Robert , Heathcote E. Jenny 
Published: December 2004

Abstract:Background/Aims:Primary biliary cirrhosis (PBC) is an autoimmune disease characterized by inflammatory destruction of small bile ducts. Primary sclerosing cholangitis (PSC) is a different, presumed autoimmune cholestatic liver disease where the bile ducts are also destroyed. In this study, apoptosis and portal triad inflammation in liver tissue from patients with PBC is examined and compared to that from patients with PSC and patients with normal liver.Methods:Explanted liver tissue from patients with PBC and PSC and normal liver from patients with metastases to liver were examined. The liver samples were stained for apoptosis using the terminal deoxynucleotidyl triphosphate (TdT)‐mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The biliary epithelial cells (BEC) were then scored on the basis of their TUNEL stain and the degree of periductal inflammation.Results:In PBC, apoptosis of BEC, as detected by the TUNEL assay, was significantly increased in the presence of inflammation. Regardless of the presence or absence of inflammation, the small bile ducts in PBC liver tissue exhibited greater evidence of apoptosis than did similar ducts from PSC or control livers.Conclusion:These findings suggest that in PBC, unlike PSC, the apoptosis of BEC in PBC is secondary to the invasion of inflammatory cells.
Single nucleotide polymorphisms and microsatellite alleles of tumor necrosis factor alpha and interleukin‐10 genes and the risk of advanced chronic alcoholic liver disease
Authors: Ladero José M. , Fernández‐Arquero Miguel , I. Tudela José , Agúndez José A.G. , Díaz‐Rubio Manuel , Benítez Julio , De La Concha Emilio G. 
Published: December 2004

Abstract:Background:Only a minority of ethanol abusers develop advanced chronic alcoholic liver disease (CALD). In CALD there is a disbalance between TNFα and IL‐10, which may be modulated by several polymorphisms at both genetic loci. Our aim has been to elucidate the possible relation between these polymorphisms and the risk of CALD.Patients and Methods:147 patients with advanced CALD and 355 healthy controls (all white Spaniards) were included. TNFα biallelic single nucleotide polymorphisms (SNP) at positions −238, −308, and −376 and IL‐10 biallelic SNP at positions −597, − 824, and − 1087 were investigated by polymerase chain reaction (PCR) amplification and dot blot hybridization. Moreover, polymorphic microsatellites TNFa, TNFb, IL‐10.R and IL‐10.G were investigated in a multiplex PCR and alleles were estimated in an automatic sequencer.Results:No differences were found in the distribution of any of the studied polymorphisms, except by an excess of the haplotype formed by the allele 11 of the microsatellite IL‐10.G and the GCC arrangement of the SNPs at the promoter of IL‐10 gene in patients (15.7 vs. 8.24%, odds ratio: 2.08, 95% C.I. = 1.31–3.31).Conclusions:The studied polymorphisms at TNFα and IL‐10 genetic loci are not clearly related to the risk of CALD. The excess of G11‐GCC haplotype found in CALD patients needs independent confirmation.
The correlation between portal myofibroblasts and development of intrahepatic bile ducts and arterial branches in human liver
Authors: Libbrecht Louis , Cassiman David , Desmet Valeer , Roskams Tania 
Published: December 2004

Abstract:Background/Aims:The development of the intrahepatic bile ducts most likely requires interactions between epithelial and mesenchymal cells. In view of the epithelial–mesenchymal interactions between portal myofibroblasts (pMFs) and biliary epithelial cells in adult diseases of the bile ducts, we investigated the presence and function of pMFs during the development of intrahepatic bile ducts, as well as the development of intrahepatic branches of the hepatic artery.Methods:We performed haematoxylin‐eosin‐stainings and immunohistochemistry for alpha‐smooth‐muscle actin, cytokeratin 19 and vimentin on serial sections of 45 fetal and postnatal liver biopsies.Results:The mesenchyme of portal tracts in the ductal plate stage devoid of a hepatic artery branch, contained numerous and diffusely scattered pMFs. Portal tracts with a hepatic artery branch were always larger than those without and showed a decreasing number of pMFs. In the remodeling stage, all portal tracts contained a hepatic artery branch, and pMFs were restricted to the periductal mesenchyme. These periductal pMFs disappeared after full incorporation of the bile duct.Conclusion:Our findings strongly suggest interactions between pMFs and epithelial cells of the developing bile ducts. The development of the intrahepatic arterial branches always precedes the incorporation of the tubular segments of the ductal plate.
Monitoring terrestrial mammals in the UK: past, present and future, using lessons from the bird world
Authors: BATTERSBY JESSAMY E. , GREENWOOD JEREMY J. D. 
Published: December 2004

ABSTRACT 1. A monitoring network for UK terrestrial mammals, the Tracking Mammals Partnership, is currently being set up to provide a coordinated programme to collect surveillance and monitoring data. 2. Monitoring UK mammals is important for a number of reasons including: setting conservation priorities; measuring the effects of conservation management; managing populations of problem species and the sustainable use of game species; assessing the effects of agriculture and other human activities; providing evidence for the need for policy change; and because of obligations under intergovernmental treaties and national legislation. 3. The bird world, largely but not solely through the work carried out by the British Trust for Ornithology, has provided a useful model for mammal surveillance and some important lessons in setting up and running a UK wide multispecies monitoring programme. 4. Lessons include the importance: of annual monitoring; of long‐term data sets of population indices rather than absolute population sizes; and of the use of volunteers in data collection. 5. Two scoping studies have been carried out to assess the feasibility and costs of setting up a mammal surveillance and monitoring network and the survey methods that could be used for different species. 6. The Tracking Mammals Partnership, comprising 23 organizations, has the remit of implementing the recommendations of the scoping studies. There are a number of programmes operating within the Partnership including the National Dormouse Monitoring Programme, the National Bat Monitoring Programme and the Breeding Bird Survey Mammal Monitoring. There are also a number of pilot schemes being tested. 7. Reports on the population trend data collected should enable more informed policy and management decisions concerning UK mammal species.
Monitoring red squirrelsSciurus vulgarisand grey squirrelsSciurus carolinensisin Britain
Authors: GURNELL J. , LURZ P. W. W. , SHIRLEY M. D. F. , CARTMEL S. , GARSON P. J. , MAGRIS L. , STEELE J. 
Published: December 2004

ABSTRACT1. In Britain, five indirect methods have been used to survey for the presence of redSciurus vulgarisand grey squirrelsS. carolinensisand to monitor population trends through time. These are: visual counts along line transects, the use of hair tubes, counts of dreys, cone line feeding transects in conifer forests and feeding signs on whole maize bait at feeding stations.2. Drey counts and cone feeding transects cannot differentiate between red and grey squirrels and are not suitable for areas where both species may be present. Hair tubes require expertise and facilities to identify hairs to species, and the relationship between tube visits and animal density in different habitats is only known for red squirrels in Sitka sprucePicea sitchensisdominated plantations. Visual counts along line transects are the simplest method to do and require little equipment. However, in general, few squirrels are seen in a single count which leads to difficulties in estimating densities.3. In this paper we present data from several studies carried out in Britain to illustrate the type of data that may be collected, and to evaluate their accuracy and precision with which they could detect population change. Hair tube lines and drey counts required the fewest number of samples to detect population change. When effort was also considered, visual transects and drey counts were more economical. However, none of the monitoring methods discussed is very precise and it may be best to monitor squirrels only in terms of relative changes in numbers or indices of numbers through time.4. Our results for red and grey squirrels also illustrated that the number of samples required to detect population change is likely to differ according to the size of the survey area. Monitoring programmes should therefore be carefully planned in relation to spatial scale in order to be able to detect real population changes. Species‐specific, quantitative thresholds to determine the significance of detected declines may need to be established for threatened UK mammals and assessed in relation to what would constitute a significant decline and whether it requires management intervention.
Endogenous Growth: Estimating the Romer Model for the US and Germany*
Authors: Gong Gang , Greiner Alfred , Semmler Willi 
Published: December 2004

AbstractBy contrasting endogenous growth models with facts, one is frequently confronted with the prediction that levels of economic variables, such as R&D expenditures, imply lasting effects on the growth rate of an economy. As stylized facts show, the research intensity in most advanced countries has dramatically increased, mostly more than the GDP. Yet, the growth rates have roughly remained constant or even declined. In this paper we modify the Romer endogenous growth model and test our variant of the model using time series data. We estimate the market version both for the US and Germany for the time period January 1962 to April 1996. Our results demonstrate that the model is compatible with the time series for aggregate data in those countries. All parameters fall into a reasonable range.
Tests for a Break in Level when the Order of Integration is Unknown*
Authors: Harvey David I. , Leybourne Stephen J. , Newbold Paul 
Published: December 2004

AbstractIn this paper, we consider tests for a break in the level of a series at an unknown point in time. It is often the case that uncertainty exists concerning the order of integration of the series; consequently, we focus on tests that are applicable when the order of integration is not known. The size and power of existing tests are analysed, and a modification to one of the established sets of tests is proposed which offers improved performance in certain circumstances.
Nucleotide diversity in populations of balitorid cave fishes from Thailand
Authors: Borowsky R. L. , Vidthayanon C. 
Published: December 2004

AbstractGenetic variabilities in four cave and eight surface species of balitorid freshwater fishes from Thailand were assessed using random amplified polymorphic DNA (RAPD). Cave species have consistently lower RAPD variation than surface species and it is hypothesized that this difference is a function of reduced population size in cave fishes. Indices of nucleotide diversity (π) were calculated from the RAPD data and are four to five times higher for the surface species than the cave species: 6.4 × 10−3 vs. 1.4 × 10−3. The π‐values for cave fishes are significantly lower than those for surface balitorids and those measured in other species using RAPD/amplified fragment length polymorphism data.
Interleukin‐1β induces matrix metalloproteinase‐1 expression in cultured human gingival fibroblasts: role of cyclooxygenase‐2 and prostaglandin E2
Authors: Sakaki H , Matsumiya T , Kusumi A , Imaizumi T , Satoh H , Yoshida H , Satoh K , Kimura H 
Published: December 2004

Objective:  Matrix metalloproteinases (MMPs) degrade extracellular matrices and are responsible for excessive connective tissue breakdown in inflammatory disorders. We investigated the mechanism of MMP‐1 expression in human gingival fibroblasts in response to the stimulation with interleukin‐1β (IL‐1β), and the role of inducible‐type cyclooxygenase‐2 (COX‐2) and prostaglandin E2 (PGE2) in the regulation of MMP‐1 expression.Materials and methods:  We stimulated cultured human gingival fibroblasts with r(h)IL‐1β, and examined the expression of MMP‐1 mRNA and protein by quantitative polymerase chain reaction and enzyme‐linked immunosorbent assay. The effect of indomethacin, dexamethasone, or cycloheximide (CHX) on the IL‐1β‐induced expression of MMP‐1 was examined. The expression of MMP‐1 in gingival fibroblasts stimulated with PGE2 was also examined.Results:  IL‐1β stimulated the expressions of mRNA and protein for MMP‐1, in cultured fibroblasts, in time‐ and concentration‐dependent manners. Pretreatment of the cells with indomethacin or dexamethasone inhibited the IL‐1β‐induced MMP‐1 expression. CHX, a protein synthesis inhibitor, also suppressed the MMP‐1 expression. IL‐1β also induced COX‐2 expression in gingival fibroblasts, and PGE2, a major COX‐2 product, was found to enhance MMP‐1 expression.Conclusion:  The IL‐1β‐induced MMP‐1 expression in gingival fibroblasts may be mediated, at least in part, by COX‐2 and its product PGE2.
Turnip vein‐clearing virus,from pathogen to host expression profile
Authors: Melcher Ulrich 
Published: December 2004

SUMMARYTaxonomy:Turnip vein‐clearing virus(TVCV) is a member of subgroup 3 of theTobamovirusgenus and is thus a member of the alphavirus‐like supergroup of positive sense RNA‐containing viruses.Physical properties:Virions, typical of tobamoviruses, are rod‐shaped and consist of a single species of four‐helix bundle capsid proteins of 17 kDa helically arranged around a 6.3 knt RNA which accounts for 5% of the virion mass. Virions are stable for years.Hosts:Members of the crucifer family are excellent hosts. Particularly noteworthy is that hosts include the model plant for molecular genetics,Arabidopsis thaliana.No non‐mechanical vectors of transmission are known.
Real‐time analysis ofPolymyxa betaeGST expression in infected sugar beet
Authors: Kingsnorth Crawford S. , Kingsnorth Amanda J. , Lyons Paul A. , Chwarszczynska Daphne M. , Asher Michael J. C. 
Published: December 2004

SUMMARYWe have tested and developed protocols for both sequence‐independent and hybridization probe real‐time PCR for the detection ofPolymyxa betaeglutathione‐S‐transferase transcripts in infected sugar beet roots. When using the test onP. betae‐free plants, no signal above the level of the non‐template control was observed. Real‐time PCR analysis of both serially diluted zoospore suspensions and infected root material demonstrated a close relationship between the threshold cycle and the amount ofP. betae. Hybridization probe real‐time analysis of infected plants sampled sequentially over 20 days from sowing showed that the levels of the transcript rose steadily after initial infection to a peak and then declined. Comparative time‐course analyses of infection in susceptible plants and a resistant wildBetaspecies indicated that, whilst transcript levels in susceptible plants showed a continuing upward trend, in the resistant species they were detectable only at an extremely low level.
The nutrient supply of pathogenic fungi; a fertile field for study
Authors: Solomon Peter S. , Tan Kar‐Chun , Oliver Richard P. 
Published: December 2004

SUMMARYPhytopathogenic fungi must feed on their hosts to propagate and cause disease. Their ability to access the rich nutrient supply offered by living plants is one of the most obvious properties that distinguish pathogens from saprophytes. Successful invasion by pathogens depends as much on their ability to utilize the available nutrient sources offered by plants as on their ability to penetrate plants and evade defensive mechanisms. Here, we review current knowledge on the nature of the nutrient supplies utilized by pathogens during infection.The available evidence is rudimentary in most cases. There is much evidence to suggest that fungal metabolism can be divided into at least two phases. The first is based on lipolysis and occurs during germination and penetration of the host. The second phase uses glycolysis and predominates during the invasion of host tissue. We also propose, mainly on theoretical grounds, that a third phase of nutrition occurs late in infection during which new spores are produced.Contrary to early assumptions, the nitrogen sources available to some pathogens appear to be abundant. The idea that nitrogen starvation is a cue that controls fungal gene expression during infection may need to be reassessed. Very little is known about the micronutrient (Fe, S, P) or vitamin supply. The knowledge gained from this research may enable the design of new antifungal strategies targeting potential weaknesses in fungal metabolism and will also impact on agronomic practices.
Variable leucine‐rich repeats of tomato disease resistance genes Cf‐2 and Cf‐5 determine specificity
Authors: Seear Paul J. , Dixon Mark S. 
Published: December 2004

SUMMARYThe tomato Cf‐2 and Cf‐5 genes confer race specific resistance to infection by the leaf mould pathogen Cladosporium fulvum. The encoded proteins induce a defence response upon recognition of the fungal Avr2 and Avr5 determinants, respectively. Each resistance protein is comprised largely of leucine‐rich repeats (LRRs) and the specificity of recognition is thought to occur through a particular domain. We have investigated this further using domain swaps between Cf‐2 and Cf‐5. Engineered chimeric genes containing portions of Cf‐2 and Cf‐5 were expressed and shown to be functional. The results clearly show that the specificity for the particular avirulence determinant is restricted to a region of each gene that encodes a subset of LRRs containing the highest level of intergenic variability. In addition, two non‐functional mutants of Cf‐5 were characterized and their significance discussed.