bluuebunny/crossref_metadata_2025 huggingface dataset:
18F‐Fluorodeoxyglucose (FDG)‐PET features of focal nodular hyperplasia (FNH) of the liver
Authors: Kurtaran Amir , Becherer Alexander , Pfeffel Franz , Müller Christian , Traub Tatjana , Schmaljohann Jörn , Kaserer Klaus , Raderer Markus , Schima Wolfgang , Dudczak Robert , Kletter Kurt , Virgolini Irene
Published: March 2003

Abstract: Aim: The aim of this paper is to describe the imaging pattern of focal nodular hyperplasia (FNH) by 18F‐fluorodeoxyglucose (18F‐FDG) positron emission tomography (PET). Methods: Eight consecutive asymptomatic patients with histologic proof of FNH underwent 18F‐FDG PET imaging. The lesions were found incidentally. The 18F‐FDG PET imaging was performed with a dedicated PET tomograph after intravenous injection of 300–370 MBq 18F‐FDG. The 18F‐FDG accumulation in the lesions was (semi)quantified by calculating the standardized uptake value (SUV) and SUV has been corrected for the lean body mass (LBM). Eight patients with liver metastases spread from melanoma (n=2) and colorectal carcinoma (n=6) served as controls. The size of the FNH lesions and of the control group ranged from 2.0 to 8.5 cm (mean 4.83 cm±2.37) and from 1.5 to 6 cm (mean 3.28±1.52), respectively. Results: While in malignant liver lesions the accumulation of 18F‐FDG was significantly increased, all FNH lesions showed normal or even decreased accumulation of 18F‐FDG. In FNH lesions, SUV ranged between 1.5 and 2.6 (mean 2.12±0.38), whereas all liver metastases showed an increased SUV ranging between 6.20 and 16.00 (mean 10.07±3.79). The SUV corrected for LMB (SUVLBM) was similar to the SUV and ranged between 0.9 and 2.2 (mean 1.81±0.41) for FNH and between 5.9 and 16.3 (mean 9.15±4.03), respectively. Conclusion: In contrast to liver metastases, there is no increased glucose metabolism in FNH in vivo. The imaging feature of FNH by 18F‐FDG‐PET imaging is not specific for FNH; however, it may be helpful to differentiate FNH from liver metastases in cancer patients if radiological methods are not diagnostic.
Cyclin D1 overexpression in hepatocellular carcinoma
Authors: Joo Mee , Kang Yun Kyung , Kim Mi‐Ran , Lee Hye Kyung , Jang Ja‐June
Published: March 2003

Abstract: Background/Aims: Cyclin D1 gene amplification and cyclin D1 protein overexpression have been reported in various human tumors, including hepatocellular carcinoma (HCC). However, their significance is still controversial. In the present study, we examined the expression of cyclin D1 and its relationships to p53 and Ki‐67 in HCCs. Methods: The expression and topological distribution of cyclin D1, p53 and Ki‐67 in 50 cases of HCC were examined immunohistochemically, and the relationship between the expression of these proteins and their pathologic features was investigated. Results: Overexpression of cyclin D1 was noted in 58% of the HCC cases, and significantly associated with a well‐differentiated histology and a low Ki‐67 labeling index (LI). Cyclin D1 overexpression was also observed in all (7 of 7) dysplastic nodules and in non‐neoplastic hepatocytes. On the other hand, aberrant p53 expression was detected in 36% of the cases, which showed positive relationships with poor differentiation, portal vein invasion, and KI‐67 LI. Only eight of the 50 cases examined (16%) were positive for both cyclin D1 and p53, which showed only a small number of cyclin D1‐positive cells. There was no significant relationship between the expressions of cyclin D1 and p53. Conclusions: Our results suggest that cyclin D1 overexpression may be an early event in hepatocarcinogenesis and that it plays a role in tumor differentiation. In addition, cyclin D1 expression is not correlated with tumor cell proliferation in HCCs.
Acute liver failure as the initial manifestation of acute leukaemia
Authors: Anderson Simon H. C. , Richardson Paul , Wendon Julia , Pagliuca Anthony , Portmann Bernard
Published: March 2003

Abstract: Background/Aims: Haematological malignancies seldom cause clinically significant liver disease. Acute liver failure as the initial manifestation of acute leukaemia is very rare and carries a very poor prognosis. Methods/Results: Three cases of acute liver failure secondary to acute leukaemia are described. Each case presented initially as acute liver failure of uncertain cause. Specific treatment for the leukaemia was instituted; however, all three patients died as a consequence of the liver failure. We describe the clinical course and relevant investigations of these patients and discuss possible mechanisms of acute liver failure in this setting. Conclusion: Acute leukaemia presenting as acute liver failure has a very poor prognosis. Although a rare cause of acute liver failure, it should be considered in any patient presenting with acute liver failure with prodromal symptoms and a raised peripheral white cell count, lactate dehydrogenase and uric acid.
Aberrant expression of cytokeratin 7 as a histological marker of progression in primary biliary cirrhosis
Authors: Yabushita Kazuhisa , Yamamoto Kazuhide , Ibuki Naohisa , Okano Nobuaki , Matsumura Shuji , Okamoto Ryoichi , Shimada Noriaki , Tsuji Takao
Published: March 2003

Abstract: Aim: We evaluated the aberrant expression of cytokeratin 7 (CK‐7) in hepatocytes as a marker of cholestasis and progression in primary biliary cirrhosis (PBC). Patients and Methods: The expression of CK‐7 was studied by immunohistochemistry in 83 cases of PBC. This expression was compared with biochemical data, the deposition of copper‐associated protein, and previous histological classifications. Results: In normal liver, CK‐7 was expressed exclusively in bile duct epithelial cells (BDE). In PBC, the expression was also observed in hepatocytes. The expression pattern was classified as follows: Grade 0, BDE as in normal; Grade 1, proliferated bile ductules; Grade 2, periportal hepatocytes in addition to proliferated bile ductules; Grade 3, intralobular hepatocytes; Grade 4, the majority of hepatocytes. The grades correlated with serum bilirubin levels but not with serum levels of biliary enzymes. A discrepancy between the CK‐7 grading and Ludwig’s classification was noted in cases with Stage 1 of the CK‐7 grading who were considered Stage 2 or 3 in Ludwig’s classification, suggesting that cholestasis and inflammatory activity might be independent events. Conclusions: These results suggest that the aberrant expression of CK‐7 in hepatocytes may be a marker of chronic cholestasis and progression in PBC.
Endotoxin and its binding proteins in chronic liver disease: the effect of transjugular intrahepatic portosystemic shunting
Authors: Kaser Arthur , Ludwiczek Othmar , Waldenberger Peter , Jaschke Werner , Vogel Wolfgang , Tilg Herbert
Published: March 2003

Abstract: Background: Gut‐derived endotoxin is insufficiently cleared by the diseased liver, and thus, is elevated in plasma of patients with chronic liver disease (CLD). Endotoxin action might be modified by binding to soluble CD14 (sCD14) and lipopolysaccharide‐binding protein (LBP), both of which have not yet been sufficiently studied in CLD.

Methods: Endotoxin, sCD14 and LBP have been determined in peripheral blood of 72 patients and 39 control subjects, and in portal and hepatic venous blood of 12 patients during transjugular intrahepatic portosystemic shunt (TIPS) implantation.

Results: Peripheral endotoxin (average 3‐fold increased compared to controls), LBP, and sCD14 plasma levels were elevated in chronic liver disease irrespective of Child stage m, preserve/absence of cirrhosis or aetiology. LBP, and sCD14. Furthermore, endotoxin levels in the portal vein (38.1 ± 6.1 pg/ml) were only slightly elevated compared to the hepatic vein (29.2 ± 4.4 pg/ml), and peripheral endotoxin levels did not increase after TIPS.

Conclusions: Decreased hepatocellular function rather than hepatic blood shunting might be responsible for endotoxemia. The elevation in LBP and sCD14 levels may be a consequence of endotoxemia.
Species‐specific variation in SIV disease progression between Chinese and Indian subspecies of rhesus macaque
Authors: Trichel A.M. , Rajakumar P.A. , Murphey‐Corb M.
Published: March 2003

Abstract: The shortage of rhesus macaques of Indian origin for acquired immune deficiency syndrome (AIDS) research has prompted a search for an alternate species. As rhesus macaques of Chinese origin are more readily obtainable, we have defined the parameters of infection in seven members of this subspecies with the primary virulent isolate, SIV/DeltaB670. Viremic peaks and set points as determined by real time polymerase chain reaction were, in general, lower than that observed in Indian origin rhesus macaques. As expected, these values were associated with maintenance of CD4+ lymphocytes and significantly longer survival, with six of seven Chinese origin animals living significantly longer than Indian origin rhesus macaques. Interestingly, these findings were associated with a selective amplification of one of two major phylogenetic groups found within the inoculum. This observation is in contrast to Indian origin animals where both phylogenetic groups are commonly identified. Together, these data suggest prudence in the design of experimental protocols using rhesus macaques of Chinese origin where survival and rapid loss of CD4+ lymphocytes are desired endpoints.
Modelling of fluid flow, heat transfer and solidification in the strip casting of a copper base alloy
Authors: Mahmoudi J. , Vynnycky M. , Fredriksson H.
Published: March 2003

A finite‐volume model has been developed and applied to analyse the solidification process of pure copper in the mould region of a continuous strip casting machine. The model was produced with the commercial program CFX, which allows this non‐linear, turbulent problem to be simulated using a modified version of the k‐ε turbulence model. The fluid flow, temperature and heat flux distributions in the mould region of the caster were computed. The shape and location of the solidification front were also determined. The effects of operating parameters, such as casting speed, superheat and the assumed values for the latent heat of fusion on the shape and location of the solidification front were investigated.
Interactions among young stages of the wolf spiders Pardosamoesta and P. mackenziana (Araneae: Lycosidae)
Authors: Buddle Christopher M.
Published: March 2003

Young stages of the wolf spiders Pardosamoesta and P. mackenziana coexist on the forest floor in a deciduous forest in central Alberta, yet nothing is known of the potential interactions between and among these ubiquitous species. An experiment, using a series of 0.25‐m2 arenas, was designed to test for inter‐ and intraspecific exploitative competition. Experimental treatments were established in the arenas in late July. Treatments involved stocking recently hatched spiderlings of each species alone, and with both species together at natural (10 spiderlings per arena) and two times the natural densities. In September the arenas were searched for Pardosa spiderlings, and the survival and mass gain of each species were determined. Other predatory arthropods, and Collembola, a common prey of young wolf spiders, were counted in the arenas before the experimental treatments were established and at the end of the experiment. No evidence for competitive interactions was uncovered, but spiderling survival was 29% for P. moesta and 20% for P. mackenziana, suggesting other mortality factors (e.g., cannibalism, intraguild predation) may be important. Top‐down effects (predatory arthropods) had no effect on Pardosa survival. Bottom‐up effects, however, were significant as treatments containing spiderlings had fewer Collembola compared to control arenas, further supporting the importance of spiders in leaf‐litter food webs.
Effects of herbivory on competition intensity in two arctic‐alpine tundra communities with different productivity
Authors: Olofsson Johan , Moen Jon , Oksanen Lauri
Published: March 2003

The effects of long‐term (11 yr) exclusion of vertebrate herbivores on competition intensity and plant community structure were studied using manipulative field experiments in two arctic‐alpine plant communities with contrasting productivity: an unproductive snowbed and a considerably more productive tall herb meadow. In the snowbed, the exclusion of herbivorous mammals resulted in a significant increase in the biomasses of vascular plants and cryptogams, whereas no corresponding response was observed on the tall herb meadow. The intensity of competition, measured with a neighbour removal experiment, did not differ significantly between three of the four habitat×treatment combinations – snowbed exclosures, meadow exclosures and open meadow plots – but was significantly lower on open snowbed plots. Our results thus suggest that the low competition intensity in the unproductive snowbed is caused by herbivorous mammals, which tend to depress plant biomass in relatively unproductive habitats. When herbivorous mammals have been excluded for a sufficiently long time to allow the build‐up of plant biomass even in unproductive habitats, between‐habitat differences in competition intensity disappear.
Role of litter decomposition for the increased primary production in areas heavily grazed by reindeer: a litterbag experiment
Authors: Olofsson Johan , Oksanen Lauri
Published: March 2003

Heavy grazing and trampling by reindeer increase nutrient cycling and primary production in areas where grasslands have replaced shrub and moss tundra. One way in which herbivores can affect nutrient cycling is through changing the litter decomposition processes. We studied the effect of herbivory on litter decomposition rate by reciprocal transplantation of litter between lightly grazed and heavily grazed areas, using the litterbag technique. We used litter from two of the most common species on the lightly grazed side, Betula nana and Empetrum nigrum, and two of the most common species on the heavily grazed side, Carex bigelowii and Deschampsia flexuosa. We found that herbivory improved litter quality by favouring species with easily decomposed litter. However, herbivory also improved litter quality by increasing the nitrogen content and lowering the C/N ratio of each species. Decomposition rates even correlated with the abundance of the plant category in question. Shrub litter decomposed faster in the lightly grazed area where shrubs were common, and graminoid litter decomposed faster in the heavily grazed area where graminoids were common. These results indicate that the decomposer micro‐organisms are adapted to the most common litter types. This study shows that detailed information about the effect of herbivory on litter quality is important to understand differences between the short‐term and long‐term effects of herbivory on nutrient cycling and primary production.
Competition betweenSphagnum magellanicumandEriophorum angustifoliumas affected by raised CO2and increased N deposition
Authors: Heijmans Monique M. P. D. , Klees Herman , Berendse Frank
Published: March 2003

The competition between peat mosses (Sphagnum) and vascular plants as affected by raised CO2and increased N deposition was studied in a glasshouse experiment by exposing peat monoliths with monocultures and mixtures ofSphagnummagellanicumandEriophorumangustifoliumto ambient (350 ppmv) or raised (560 ppmv) atmospheric CO2concentrations, combined with low (no N addition) or high (5 g m−2yr−1added) N deposition. Growth of the two species was monitored for three growing seasons.  The presence ofEriophorumdid not affectSphagnumbiomass, becauseEriophorumdensity did not become high enough to severely shade the moss surface. In contrast,Sphagnumhad a negative effect onEriophorumbiomass, particularly on the number of flowering stems. Possibly, the presence of a livingSphagnumlayer decreased nutrient availability toEriophorumby immobilising nutrients mineralised from the peat.  Raised CO2and/or increased N deposition did not change these competitive relationships betweenSphagnumandEriophorum, but had independent effects. Raised CO2had a positive effect both onSphagnumandEriophorumbiomass, though onEriophorumthe effect was transient, probably because of P limitation. Nitrogen addition had a direct negative effect onSphagnumheight growth in the first growing season, but by the third year an increased shoot density had cancelled this out, so no N effect onSphagnumbiomass was present at the end of the experiment. The response ofEriophorumto N addition was small; N availability appeared not to limit its growth.
Impact of non‐indigenous species on natives enhanced by anthropogenic alteration of selection regimes
Authors: Byers James E.
Published: March 2003

Changes in environmental conditions often reverse outcomes of competitive interactions among species. Such context dependency implies that the speed, persistence, and ubiquity of anthropogenic habitat alterations may suddenly put even previously well‐adapted native species at a competitive disadvantage with non‐native species. That is, anthropogenic disturbance may so drastically alter environments that a native species finds itself in an environment that in key ways is just as novel as it is to a non‐indigenous species. Extreme disturbances may thereby erase a native species’ prior advantage of local environmental adaptation accrued during its long‐term incumbency over evolutionary time. I document examples from two areas of dramatic human alteration of selection regimes – eutrophication and the selective removal of top predators – that support this mechanism. Additionally, I highlight ways in which this mechanism is experimentally testable. Alteration of selection regimes may prove to be a powerful explanation for the enhanced success and impact of biological invasions in our globally disturbed biosphere.
Habitat coupling in lake ecosystems
Authors: Schindler Daniel E. , Scheuerell Mark D.
Published: March 2003

Lakes are complex ecosystems composed of distinct habitats coupled by biological, physical and chemical processes. While the ecological and evolutionary characteristics of aquatic organisms reflect habitat coupling in lakes, aquatic ecology has largely studied pelagic, benthic and riparian habitats in isolation from each other. Here, we summarize several ecological and evolutionary patterns that highlight the importance of habitat coupling and discuss their implications for understanding ecosystem processes in lakes. We pay special attention to fishes because they play particularly important roles as habitat couplers as a result of their high mobility and flexible foraging tactics that lead to inter‐habitat omnivory. Habitat coupling has important consequences for nutrient cycling, predator‐prey interactions, and food web structure and stability. For example, nutrient excretion by benthivorous consumers can account for a substantial fraction of inputs to pelagic nutrient cycles. Benthic resources also subsidize carnivore populations that have important predatory effects on plankton communities. These benthic subsidies stabilize population dynamics of pelagic carnivores and intensify the strength of their interactions with planktonic food webs. Furthermore, anthropogenic disturbances such as eutrophication, habitat modification, and exotic species introductions may severely alter habitat connections and, therefore, the fundamental flows of nutrients and energy in lake ecosystems.
Parasitoids induce production of the dispersal morph of the pea aphid, Acyrthosiphon pisum
Authors: Sloggett John J. , Weisser Wolfgang W.
Published: March 2003

In animals, inducible morphological defences against natural enemies mostly involve structures that are protective or make the individual invulnerable to future attack. In the majority of such examples, predators are the selecting agent while examples involving parasites are much less common. Aphids produce a winged dispersal morph under adverse conditions, such as crowding or poor plant quality. It has recently been demonstrated that pea aphids, Acyrthosiphon pisum, also produce winged offspring when exposed to predatory ladybirds, the first example of an enemy‐induced morphological change facilitating dispersal. We examined the response of A. pisum to another important natural enemy, the parasitoid Aphidius ervi, in two sets of experiments. In the first set of experiments, two aphid clones both produced the highest proportion of winged offspring when exposed as colonies on plants to parasitoid females. In all cases, aphids exposed to male parasitoids produced a higher mean proportion of winged offspring than controls, but not significantly so. Aphid disturbance by parasitoids was greatest in female treatments, much less in male treatments and least in controls, tending to match the pattern of winged offspring production. In a second set of experiments, directly parasitised aphids produced no greater proportion of winged offspring than unparasitised controls, thus being parasitised itself is not used by aphids for induction of the winged morph. The induction of wing development by parasitoids shows that host defences against parasites may also include an increased rate of dispersal away from infected habitats. While previous work has shown that parasitism suppresses wing development in parasitised individuals, our experiments are the first to demonstrate a more indirect influence of parasites on insect polyphenism. Because predators and parasites differ fundamentally in a variety of attributes, our finding suggests that the wing production in response to natural enemies is of general occurrence in A. pisum and, perhaps, in other aphids.
Altitudinal increase of mobile carbon pools in Pinus cembra suggests sink limitation of growth at the Swiss treeline
Authors: Hoch Günter , Popp Marianne , Körner Christian
Published: March 2003

Low temperature driven carbon shortage is often assumed to explain slow growth and treeline formation at high elevations. To test this hypothesis, we analysed mobile carbon pools in Pinus cembra across the treeline ecotone in the Swiss Alps. Concentrations of non‐structural carbohydrates (NSC) in needles, branches, stems and roots, as well as lipids (acylglycerols) in all woody tissues were measured throughout the growing season. Starch was the most prominent non‐structural carbon compound in needles, whereas lipids represented 50–75% of the mobile carbon compounds in wood. The relative seasonal variation of the lipid fraction was very small, but due to the high absolute amount of lipids, the annual variability of carbon in lipids exceeded that of NSC in woody tissues. Mobile carbon compounds were highly abundant throughout the year and were never significantly depleted. Across a 110 m altitudinal transect from timberline to the uppermost site of tree existence, NSC and lipid concentrations generally increased. This trend became even more pronounced when the increasing structural density of tissues at higher elevations was accounted for. An estimation of the whole tree mobile carbon concentration (fraction of mobile carbon compounds within the whole tree biomass) also revealed an increasing trend of NSC and lipid pools with elevation. We therefore conclude that carbon limitation is unlikely to be responsible for reduced tree growth at the alpine treeline studied. Increased concentrations of NSC and lipids at the upper tree limit rather suggest that sink activity is limited. Hence, treeline formation is most likely the result of a direct thermal restriction of tissue formation (investment in structures) under otherwise sufficient carbon assimilation during the growing season.
Grouping increases the ability of the social rodent, Octodon degus, to detect predators when using exposed microhabitats
Authors: Ebensperger Luis A. , Wallem Petra K.
Published: March 2003

We examined the hypothesis that a main benefit of group‐living in the hystricognath rodent, Octodon degus (common degu), is to decrease individual risk of predation. During a first series of field observations, we contrasted group size of degus when using covered microhabitats with that of degus using exposed patches. During a second set of field observations, we assessed how distance to detection and to escape by degus varied with group size upon the approach of a potential human predator. Degus in exposed patches formed larger groups than degus in covered microhabitats. After excluding the influence of nearest burrow to focal subjects, we found that degus of larger groups detected an approaching human predator at a greater distance than degus of smaller groups. Likewise, degus of larger groups escaped to nearby burrows at a greater distance from the approaching predator than degus of smaller groups. All these pieces of evidence support the predatory risk hypothesis according to which group‐living in degus functions to reduce the risk of predation.
Vertically transmitted fungal endophytes: different responses of host‐parasite systems to environmental conditions
Authors: Ahlholm Jouni U. , Helander Marjo , Lehtimäki Silja , Wäli Piippa , Saikkonen Kari
Published: March 2003

The relationship between vertically transmitted asexual fungal grass endophytes and their hosts is considered to be mutualistic. Results from agronomic field support this line of reasoning but recent studies have shown more variable results in natural systems. We investigated how high and low nutrient and water treatments affected biomass allocation patterns of endophyte‐infected and uninfected Festuca pratensis and F. rubra in greenhouse experiments over two growing seasons. Irrespective of infection status, both grass species showed improved performance on highly fertilized and watered soils. However, infected F. pratensis plants produced larger tillers than endophyte‐free plants on soil low in nutrients and water in the first growing season, although they (E+) otherwise showed decreased performance on nutrient‐poor soil. In low nutrient and water conditions, endophyte‐infected plants produced less tillers and had lower total biomass compared to uninfected plants, and displayed a negative phenotypic correlation between seed production and vegetative growth. The latter indicates costs of reproduction when the plant shares common resources with the fungal endophyte. However, endophyte infection status (E+, E−) interacted significantly with the soil fertilisation in terms of plant growth, having a stronger positive effect on growth in infected F. pratensis plants. In F. rubra, endophyte‐infected plants showed higher vegetative growth in fertilized and watered soils compared to uninfected plants. However, infected plants tended to produce fewer inflorescences. This had no effect on seed production, perhaps because seed production was partly replaced by asexual pseudovivipary. Contrary to the general assumption in the literature that fungal endophytes are plant mutualists, these findings suggest that the costs of endophytes may outweigh their benefits in resource limited conditions. However, the costs of endophyte infections appear to differ among the grass species studied; costs of endophytes were mainly detected in F. pratensis under low nutrient conditions. We propose that differences in response to endophyte infection in these species may depend on the differences in life‐history strategies and environmental requirements of these two fescue and fungal species and may change during the life span of the plant.
Bright autumn colours of deciduous trees attract aphids: nutrient retranslocation hypothesis
Authors: Holopainen Jarmo K. , Peltonen Petri
Published: March 2003

We propose an alternative hypothesis to the handicap‐signalling hypothesis, to explain the high number of specialist aphids on tree species having bright autumn colour. Since birch aphids actively seek the first yellowing leaves for breeding in autumn, it is obvious that autumn colour of foliage does not repel migrating aphids. We suggest that aphids use bright colours as a cue to detect individual trees and leaves that are good sources of nitrogen in the form of amino acids in autumn. The active formation of bright‐coloured pigments in leaves is needed to protect them from photo inhibition during energy consuming nutrient retranslocation under cold autumn conditions. During nutrient export from leaves, nitrogen is in the form of amino acids in the sieve elements and easily available for aphids. Therefore, bright colours may act as a signal of easily available high‐quality food for viviparous aphid migrants that are selecting suitable trees for their sexual offspring reproduction. The females of sexual generation grown on the better quality food probably can oviposit the over‐wintering eggs to the twigs in higher numbers, which may have an adaptive advantage in competition with conspecific females.
Microbiota, fauna, and mesh size interactions in litter decomposition
Authors: Bradford Mark A. , Tordoff George M. , Eggers Till , Jones T. Hefin , Newington John E.
Published: March 2003

Plant litter decomposition is a key process in carbon and nutrient cycling. The critical role of soil‐faunal community composition in decomposition has been demonstrated using different mesh size litterbags to control exposure of litter to different faunal size classes. However, the faunal community surrounding the litterbags has not been manipulated despite potentially large indirect effects of their activity on biotic and abiotic processes that control litter decomposition at the habitat‐scale.  We combined microcosm and litterbag techniques to facilitate a more comprehensive understanding of the role of direct and indirect effects of soil‐faunal community composition on litter decomposition. We placed litterbags of three mesh sizes across model grassland miniecosystems manipulated to enable communities containing 1) microfauna; 2) micro‐ and meso‐fauna; 3) micro‐, meso‐ and macro‐fauna. All communities contained bacteria and fungi. The approach permitted correction of mesh size artefacts inherent to field studies. Indirect effects have been divided into two separate terms, direct‐indirect effects and indirect effects.  Decomposition in micromesh litterbags was significantly decreased by the indirect effects of meso‐ and macro‐fauna. In macrofauna communities, increased mesh size significantly increased decomposition through mesh size per se and faunal effects. Relative effects of manipulated faunal community composition on litter mass loss and C:N ratio were equivalent for green and senesced litter. The presence of meso‐ and macro‐fauna increased litter decomposition rate overall despite inhibiting decomposition by microfauna, bacteria and fungi through indirect effects.
Innervation pattern and Ca2+ signalling in labial salivary glands of healthy individuals and patients with primary Sjögren’s syndrome (pSS)
Authors: Pedersen Anne Marie , Dissing Steen , Fahrenkrug Jan , Hannibal Jens , Reibel Jesper , Nauntofte Birgitte
Published: March 2003

Abstract: We have characterised the innervation pattern and intracellular Ca2+‐signalling in labial salivary glands (LSG) of 16 patients with primary Sjögren’s syndrome (pSS) and 27 healthy controls. Numerous immunoreactive nerve fibers (IRF) containing vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide (PACAP) were found around acini, ducts and blood vessels. Substance P (SP)‐, neuropeptide Y‐, tyrosine hydroxylase‐ and nitric oxide synthase‐IRF were mainly surrounding ducts and blood vessels. The majority of pSS patients had inflamed LSG and the presence of focal lymphocytic infiltrates (FI) were more frequent and pronounced as compared with healthy controls. In areas with normal or diffusely inflamed LSG tissue, pSS patients demonstrated the same distribution of IRF as healthy controls with similar histology. However, IRF were absent in central areas of FI both in pSS and age‐matched healthy controls. Although all pSS patients had hyposalivation, stimulation with acetylcholine, norepinephrine, phenylephrine, isoproterenol, VIP, PACAP, SP, adenosine 5′‐triphosphate and uridine 5′‐triphosphate induced the same increase in the intracellular free Ca2+ concentration in LSG acini from both pSS patients and healthy controls, indicating the presence of functional receptor systems in vitro.
Hepatitis C virus infection and oral lichen planus: a report from the Netherlands
Authors: Meij E. H. , Waal I.
Published: March 2003

Abstract: The reported frequency of anti‐hepatitis C virus (HCV) antibodies in groups of cutaneous lichen planus (CLP) and/or oral lichen planus (OLP) patients varies from about 4% to 65%. Most of these studies have been performed in countries with a high overall prevalence of HCV infection in the general population, such as the southern European countries and Japan. Limited data are available from areas with a low prevalence of HCV infection. Therefore, we investigated the prevalence of HCV infection in a series of 55 patients with OLP in the Netherlands, which apparently has a low prevalence of HCV infection. None of the 55 patients revealed serological evidence of antibodies to HCV. The present data suggest that HCV infection in OLP patients in the Netherlands is probably not very common. A larger study group with a sex‐ and age‐matched control group is required to advise against routine serological examination for HCV infection in Dutch OLP patients.
Reduction of syndecan‐1 expression is associated with dysplastic oral epithelium
Authors: Soukka Tero , Pohjola Jaana , Inki Pirjo , Happonen Risto‐Pekka
Published: March 2003

Abstract: Syndecans are a family of integral membrane proteoglycans that participate in cell‐matrix interactions and growth factor binding. Syndecan‐1 expression is induced during keratinocyte differentiation and reduced in squamous cell carcinomas. The purpose of this study was to examine the alteration in syndecan‐1 expression in dysplastic oral epithelium. Sixty‐six oral biopsy specimens (43 epithelial dysplasias, 3 carcinoma in situ and 20 squamous cell carcinomas) were studied using immunohistochemical methods. The normal epithelium specimens were highly positive for syndecan‐1. Fifteen of 46 dysplasias or carcinoma in situ specimens showed negative or weak staining for syndecan‐1, two of which were totally negative. Intermediate and strong staining were observed in 17 and 14 dysplasias or carcinoma in situ specimens, respectively. Thirteen (65%) squamous cell carcinomas showed negative or weak staining for syndecan‐1, seven of which were totally negative. Only three carcinomas had a strong syndecan‐1 expression. Four of the 34 patients with dysplasia who were followed up developed squamous cell carcinoma. All these dysplasias had weak or totally negative syndecan‐1 expression. The results suggest that the loss of syndecan‐1 is associated with dysplastic changes in oral epithelium.
Vascular endothelial growth factor (VEGF) expression in oral tissues: possible relevance to angiogenesis, tumour progression and field cancerisation
Authors: Carlile J. , Harada K. , Baillie R. , Macluskey M. , Chisholm D. M. , Ogden G. R. , Schor S. L. , Schor A. M.
Published: March 2003

Abstract: The aim of this study was to assess whether vascular endothelial growth factor (VEGF) expression in oral tissues is associated with angiogenesis, disease progression or field cancerisation. Vascularity and VEGF immunoreactivity were quantified in 68 archival specimens including normal oral mucosa (NOM), dysplasia (DYS) and squamous cell carcinoma (SCC). Vascularity increased significantly with disease progression; it was also higher in NOM adjacent to SCC than in NOM from healthy tissue, suggesting an association with field cancerisation. VEGF expression in epithelial cells was evaluated using two antibodies and three indices. VEGF indices and vascularity were not directly correlated. The expression of VEGF was similar in all DYS and NOM specimens, whether or not adjacent to a concurrent lesion. A comparison of SCC with NOM or DYS led to opposite results, depending on the VEGF antibody and index used. We conclude that VEGF expression in the oral mucosa may play a physiological role, but does not appear to be associated with angiogenesis, field cancerisation or transition to dysplasia. Further studies concerned with tumour development require examining specific VEGF isoforms and standardisation of the methodology.
Oral manifestations in 45 HIV‐positive children from Northern Thailand
Authors: Khongkunthian P. , Grote M. , Isaratanan W. , Piyaworawong S. , Reichart P. A.
Published: March 2003

Abstract: Forty‐five Northern Thai children with HIV infection or AIDS were examined for oral manifestations. Of these children, 51.1% (n=23) were asymptomatic (category N), 48.9% were mildly, moderately or severely symptomatic (category A, B, C) and 48.9% (n=22) revealed oral lesions. Eleven patients (24.4%) showed one oral lesion, eight (17.8%) had two and three (6.6%) had three oral lesions. Erythematous candidiasis was the most common lesion (17.8%). Oral hairy leukoplakia was seen in 6.7% (n=3). Geographic tongue, not usually considered to be associated with HIV infection, was seen in 6.7% (n=3). Only 15 patients (33.3%) received antiretroviral therapy (ART). Comparison of patients with or without ART did not show differences in the prevalence of oral lesions. More studies in Thai HIV‐infected children are needed to reveal the prevalence of oral manifestations, as well as for the predictive value of the most common or specific oral manifestations.
Histopathological and immunohistochemical analysis of calcifying odontogenic cysts
Authors: Yoshida Mitsuhide , Kumamoto Hiroyuki , Ooya Kiyoshi , Mayanagi Hideaki
Published: March 2003

Method and Results: Calcifying odontogenic cysts (COCs) were examined histopathologically and immunohistochemically to characterize the histological and cytological properties of these lesions. Histopathologically, COCs showed thin or thick lining epithelium with ghost cells. COCs were classified according to proliferative type or nonproliferative type lining epithelium, the presence or absence of ameloblastomatous appearance, and the presence or absence of odontoma in the cyst walls. Immunohistochemically, amelogenin protein was expressed chiefly in ghost cells, whereas cytokeratin 19 (CK19) and bcl‐2 proteins were expressed chiefly in lining epithelial cells. The proportion of cases positive for bcl‐2 protein was slightly higher in COCs with odontoma than in those without odontoma. Lining epithelial cells sporadically showed positive reactions for Ki‐67 antigen. Mean Ki‐67 labeling index was slightly greater in COCs with proliferative type lining epithelium, COCs with ameloblastomatous appearance of the cyst walls, and COCs with odontoma of the cyst walls than in COCs without these histological features. Our results suggest that ghost cells or lining epithelial cells show ameloblastic cytodifferentiation or odontogenic epithelial characteristics, that bcl‐2 protein is associated with survival of lining epithelial cells in COCs, and that high proliferation potential is associated with ameloblastomatous proliferation or combined odontoma. COCs exhibited various histological features with several transitional forms, and immunohistochemical examinations revealed little or no difference in cytodifferentiation and cellular activity among COCs.

Conclusion: We conclude that COCs with various histological features have neoplastic potential and may not be separate entities within the same histological spectrum.
Altered expression of collagen XVII in ameloblastomas and basal cell carcinomas
Authors: Parikka Mataleena , Kainulainen Tiina , Tasanen Kaisa , Bruckner‐Tuderman Leena , Salo Tuula
Published: March 2003

Background: Collagen XVII (BP180) is an epithelial transmembrane protein, which presumably plays a role in cell migration and differentiation under both physiological and pathological conditions. Ameloblastoma, the most common odontogenic neoplasm, and basal cell carcinoma (BCC) of the skin exhibit similar growth patterns and share histological features.

Methods: Here, we examined the distribution and expression of collagen XVII in ameloblastomas and BCCs using immunohistochemistry and non‐radioactive in situ hybridization. In both tumors, the distribution of collagen XVII varied in different parts of the lesions.

Results: In ameloblastomas, immunostaining for collagen XVII was usually localized in the basal and suprabasal cells of the tumor nests, although in some tumors, a diffuse intracellular staining was detected in the central cells of the neoplastic islands. In BCCs, collagen XVII was mostly seen as diffuse cytoplasmic staining in some central and peripheral cells of the tumor islands and also at the cell membranes in the basal keratinocytes of the epidermis overlying the tumor nests. Double immunostaining with antibody against γ2 chain of laminin‐5 showed that these two components of the keratinocyte adhesion complex are usually co‐localized in ameloblastomas and BCCs. In both tumors, collagen XVII mRNA was found in the basal epithelial cells and in some central and peripheral cells of the tumor islands, while the stromal cells were negative.

Conclusions: These findings indicate that the expression of collagen XVII may be differentially regulated in various parts of the tumor. Diffuse intracellular distribution of collagen XVII and a consequent loss of critical cellular attachments may contribute to the infiltrative and progressive growing potential of tumors.
The treatment of oral aphthous ulceration or erosive lichen planus with topical clobetasol propionate in three preparations: a clinical and pilot study on 54 patients
Authors: Muzio Lorenzo Lo , Della Valle Antonio , Mignogna Michele D. , Pannone Giuseppe , Bucci Paolo , Bucci Eduardo , Sciubba James
Published: March 2003

Background: This study evaluated the clinical use of a corticosteroid in three preparations (topical clobetasol propionate ointment, clobetasol propionate in an oral analgesic base, and clobetasol propionate in an adhesive denture paste).

Methods: Fifty‐four patients (34 males and 20 females) with a history of vesiculo‐ulcero‐erosive oral lesions were selected: 24 with oral erosive lichen planus and 30 with aphthae. The subjects enrolled were randomly divided into three groups, each of 18 patients (10 with aphthae and 8 with lichen planus): the first was treated with topical clobetasol propionate ointment (0.05%) directly on the lesion(s) three times a day; the second with clobetasol propionate in an adhesive denture paste in equal amounts (1:1) two times a day; the third with clobetasol propionate in an oral analgesic base (Orabase‐B) in equal amounts (1:1) two times a day. Each subject scored his or her symptoms daily from most severe (7) to none (0) by verbal assessments using a categorical scale.

Results: In all cases, the administration of the corticosteroid was effective in producing remission of symptoms in each group of patients. Significant differences (P<0.05) between groups were determined by the Kruskal–Wallis test. The Dunn test was used in order to detect which group differs from the others; clobetasol and adhesive denture paste correlated with an early remission of pain in lichen and apthous lesions.

Conclusion: The results suggest that topical application of clobetasol in an adhesive denture paste is an effective drug for symptomatic oral vesiculo‐erosive and/or ulcerative lesions.
Betel quid‐associated oral lesions and oral Candida species in a female Cambodian cohort
Authors: Reichart P. A. , Schmidtberg W. , Samaranayake L. P. , Scheifele C.
Published: March 2003

Background:  Betel quid chewing (BQC) is still prevalent among elderly Cambodian women and is associated with a wide variety of oral mucosal lesions. BQC has also been associated with a reduced rate of dental caries and changes in the oral microbiological flora.

Methods:  Since no studies were available on the impact of BQC on the oral carriage of Candida species, in this study oral swabs (Fungiquick®, Hain Diagnostika, Germany) were taken from the tongue and palate of 48 Cambodian women with BQC habit (study group) and 13 control subjects without BQC habit (control group) to determine the spectrum of Candida species in these two groups. In addition, we investigated lesions of the oral mucosa likely to be associated with BQC habit in both study and control groups.

Results:  The median duration of BQC was 10 years (range 10 months−30 years). The following oral lesions were found in the study group: betel chewer's mucosa (85.4%), oral leukoplakia (8.3%), leukoedema (37.5%) and oral lichen planus (4.2%). Oral candidiasis was seen neither in BQ‐chewers nor in controls. Candida spp. were found in 70.8% of the cases (controls 69.2%). Whilst C. albicans was isolated from 27.1% of the study cohort, C. tropicalis was the second most common isolate. One control case was colonised by C. dubliniensis – the first report of this organism from a Cambodian population. There was no significant difference in the candidal carriage rate or the Candida species isolated between the study and the control group.

Conclusions:  Mycological findings from the present study do not indicate that BQC has a significant effect on oral colonisation by Candida species.
Analysis of the Ki‐67 antigen at the invasive tumour front of human oral squamous cell carcinoma
Authors: Tumuluri V. , Thomas G. A. , Fraser I. S.
Published: March 2003

Background:  It is hypothesised that cell proliferation, as measured by the Ki‐67 labelling index (LI) at the invasive tumour front (ITF) was directly related to the histological grade in human oral squamous cell carcinomas (SCCs).

Methods:  Tissues from 42 human oral SCCs were collected and stained with an antibody directed against the Ki‐67 antigen using an advanced polymer staining system. Quantitation of the immunopositive cells was performed on two parallel sections at the invasive tumour front (ITF), using an image analyser. The Ki‐67 LI was expressed as the number of positive nuclei/mm2 of epithelium. The control tissue used was normal epithelium at the excision margin.

Results:  The mean Ki‐67 LI for oral SCCs at the ITF was significantly greater than that for the excision margin tissue (P < 0.0001). There was a positive association between increasing Ki‐67 LI and increasing Broders' grade (P < 0.05), with a well‐differentiated tumour having the lowest mean Ki‐67 LI (1549 ± 806) and a poorly differentiated tumour having the highest value (2232 ± 771). A similar trend was observed between the mean Ki‐67 LI and Bryne's multifactorial grading system.

Conclusions:  It was concluded from this study that cell proliferation (as measured by the Ki‐67 antigen) at the ITF had a strong positive relationship with histological grading in human oral SCC.
Sparganosis: a rare case of the oral cavity
Authors:   Anak Iamaroon,   Kom Sukontason, Sukontason Kabkaew
Published: March 2003

Sparganosis is a rare parasitic disease. We here reported an extremely rare case of intraoral sparganosis in a 21‐year‐old Thai female. Clinically, the lesion presented as an asymptomatic nodule 1 cm × 1 cm in the left upper labial mucosa. An excisional biopsy was performed and the pathological examinations revealed a larva of a sparganum surrounded by a fibrous capsule heavily infiltrated with eosinophils. Excision of the lesion was curative. The possible route of infection of the patient might be due to drinking water, contaminated with Cyclops containing procercoid larvae.
Facial pain, depression and stress – connections and directions
Authors: Korszun Ania
Published: March 2003

Chronic facial pain is associated with depression, stress and other chronic pain disorders such as fibromyalgia. There is growing evidence that all these conditions share underlying pathophysiological processes. This review explores this relationship and examines the role of the main stress hormone axis, the hypothalamic‐pituitary‐adrenal axis, in the pathogenesis of facial pain including possible future therapeutic approaches.