bluuebunny/crossref_metadata_2025 huggingface dataset:
A pilot study of recombinant interferon beta‐1a for the treatment of chronic hepatitis C
Authors: Habersetzer François , Boyer Nathalie , Marcellin Patrick , Bailly François , Ahmed Si Nafa Si , Alam John , Benhamou Jean Pierre , Trépo Christian
Published: March 2003

Abstract: Aims: Interferon alpha monotherapy induces a sustained response in less than 20% of patients treated for chronic hepatitis C. Interferon beta represents a potential therapeutic alternative for the treatment of chronic hepatitis C. The aim of this pilot study was to evaluate the efficacy and tolerance of recombinant interferon beta‐1a administered subcutaneously. Methods: Twenty‐one drug‐naive patients with chronic hepatitis C were treated with recombinant interferon beta‐1a administered, subcutaneously, for 24 weeks using two different regimens: 9 MU, three times per week (n=11) and 12 MU, three times per week (n=10). Results: At the end of the treatment period, nine (43%) patients had a biochemical and virological response (i.e. normal ALT and absence of hepatitis C virus RNA by PCR). Four of these patients were in the 9 MU group and five in the 12 MU group. A biochemical and virological sustained response occurred in four (19%) patients, all in the 9 MU dose group. The 4 patients with a sustained response maintained their response during a follow‐up period of 33 to 58 months. Side effects were mild and 19 (90%) patients completed the treatment period. Conclusions: The results of this pilot study indicate that interferon beta‐1a administered subcutaneously is an effective therapy for some patients with chronic hepatitis C, and suggest that interferon beta‐1a deserves further evaluations in larger trials especially in combination with ribavirin.
Divergent expression of midkine in the human fetal liver and kidney: immunohistochemical analysis of developmental changes in hilar primitive bile ducts and hepatocytes
Authors: Kato Masako , Shinozawa Takao , Kato Shinsuke , Terada Tadashi
Published: March 2003

Abstract: Background/Aims: Midkine (MK) is a novel heparin‐binding growth factor whose gene has been identified in embryonal carcinoma cells in early stages of retinoic acid‐induced differentiation. In this study, we investigated the developmental expression of MK protein in the human fetal liver and kidney. Methods: Twenty‐one specimens each of the liver and kidney from fetuses (gestational weeks from 9 to 40) and neonates less than 4 weeks old were examined. Immunohistochemical and Western blot analyses were performed using a rat IgG2a monoclonal antibody against the carboxyl terminal region of human MK. Results: Immunohistochemical analysis revealed MK expression in the human fetal liver and kidney. The MK expression in the fetal liver showed a strong reaction from 9 to 16 gestational weeks. MK was expressed in the ductal plate, migrating biliary cells and newly formed bile ducts, and in hepatocytes of the hilar region in all specimens in the first and second trimesters. By contrast, the MK expression decreased gradually and was weak or not detected in the third trimester and neonatal period. However, MK expression in the kidney was found at 16 gestational weeks, as well as during both gestation and the neonatal period. Conclusions: Divergent MK‐expression was detected in the human fetal liver and kidney, and its expression may be related to fetal development, maturation, and functions of the liver and kidney.
Clearance of hepatitis B surface antigen in chronic carriers of hepatitis delta antibodies
Authors: Niro Grazia Anna , Gravinese Eleonora , Martini Elisabetta , Garrubba Maria , Facciorusso Domenico , Conoscitore Pasquale , Di Giorgio Giuseppe , Rizzetto Mario , Andriulli Angelo
Published: March 2003

Abstract: Background/Aims: We evaluated the rate of seroclearance of the hepatitis B surface antigen (HBsAg) and its clinical significance in patients with chronic hepatitis delta virus (HDV). Methods: Antibody to HDV was tested in HBsAg‐positive subjects admitted to our Hospital from 1991 to 1995. In 1997, a biochemical and virologic study was performed in the surviving anti‐HD‐positive patients who had not undergone transplantation. As a control, a cohort of 106 HBsAg‐positive, anti‐HD‐negative patients was studied. Results: One hundred and forty‐one subjects were originally positive for anti‐HD. After 4 years of follow‐up, six of the 60 patients who underwent re‐evaluation (10%) had cleared the HBsAg: three of the six patients had minimal changes at the initial liver histology and normal ALT, whereas in the remaining three patients with chronic active hepatitis ALT normalized during the observation. Anti‐HD persisted in five of the six patients. Only one patient had raised anti‐HBs. In contrast, three of 106 HBsAg carriers without HDV infection (2.8%) cleared the HBsAg within the same time and seroconverted to anti‐HBs (p=0.002). Conclusion: HBsAg clearance is increased over the years in HDV patients compared to ordinary HBsAg carriers, and is often associated with improvement of HDV disease without seroconversion to anti‐HBs.
Effect of in situ hypothermic perfusion on intrahepatic pO2 and reactive oxygen species formation after partial hepatectomy under total hepatic vascular exclusion in pigs
Authors: Heijnen Bob H. M. , Straatsburg Irene H. , Kager Liesbeth M. , Van Der Kleij Ad J. , Gouma Dirk J. , Van Gulik Thomas M.
Published: March 2003

Abstract: Aim:  This study examined attenuation of ischemia and reperfusion (I/R) induced liver injury during liver resections by hypothermic perfusion of the liver under total hepatic vascular exclusion (THVE). Method: Reactive oxygen species (ROS) formation, microcirculatory integrity and endothelial cell damage were investigated. Left hemihepatectomy (LHX) was performed without in situ perfusion (control‐LHX, n = 5) or with concomitant in situ perfusion with hypothermic (4 °C) Ringer‐glucose (cold‐LHX, n = 5) or normothermic (38 °C) Ringer‐glucose (warm‐LHX, n = 5). Glutathione (GSH) and malondialdehyde (MDA) concentrations, tissue pO2 levels and hyaluronic acid (HA) uptake capacity were determined. Results: After cold, warm and control‐LHX, 24 h survival was 5/5, 0/5 and 3/5, respectively. GSH levels were best preserved after cold‐LHX during reperfusion. MDA levels increased in all groups without significant differences between the groups during reperfusion. Tissue pO2 levels increased after cold‐LHX whereas after warm‐LHX and control‐LHX, pO2 levels decreased during reperfusion. HA uptake capacity remained normal after cold‐LHX. After warm‐LHX and control‐LHX, HA uptake capacity decreased after 6 h of reperfusion but recovered after 24 h of reperfusion in the control‐LHX group. Conclusion: Moderate hypothermic perfusion protects the liver from I/R injury during LHX under THVE. This protective effect depended on maintenance of liver microcirculation rather than a reduction in ROS formation.
Endometrial function in vervet monkeys (Cercopithecus aethiops): morphology, β3 integrin and insulin‐like growth factor binding protein‐1 expression during the menstrual cycle and pregnancy in the normal and disrupted endometrium
Authors: Seier J. V. , Chwalisz K. , Louw J. , Van Der Horst G. , De Kock M. , Du Toit D. , Laubscher J. A.
Published: March 2003

Abstract: The expression of endometrial β3 integrin and insulin‐like growth factor binding protein‐1 (IGFBP‐1) was studied in cycling and pregnant vervet monkeys. There were clear changes of β3 integrin expression during the menstrual cycle, with the strongest immunostaining observed on day 26. Moderate to strong expression was observed during pregnancy. The expression of IGFBP‐1 during the menstrual cycle was weak but upregulated during pregnancy with moderate to strong staining. The administration of a single dose of onapristone at 10 mg/kg on days 17, 21 and 22 of the menstrual cycle, followed by a biopsy on days 22, 22 and 26, respectively, and during pregnancy (34–44 days menstrual age) 24 h before the biopsy, disrupted and desynchronized the endometrium. However, no effect on β3 integrin expression could be observed and staining reflected the untreated patterns. The same applied to IGFBP‐1 except that during pregnancy the expression of this protein was reduced or abolished. The results suggest that β3 integrin is associated with endometrial receptivity in vervet monkeys and that IGFBP‐1 plays an important role during pregnancy in this species. The administration of onapristone appeared to only influence IGFBP‐1 expression. To our knowledge, this is the first time that these endometrial proteins have been investigated in vervet monkeys. This study should therefore contribute to improving our understanding of the reproductive function of this species.
Postnatal pre‐ and postexposure passive immunization strategies: protection of neonatal macaques against oral simian–human immunodeficiency virus challenge
Authors: Hofmann‐Lehmann R. , Vlasak J. , Rasmussen R.A. , Jiang S. , Li P.L. , Baba T.W. , Montefiori D.C. , Bernacky B.J. , Rizvi T.A. , Schmidt R. , Hill L.R. , Keeling M.E. , Katinger H. , Stiegler G. , Cavacini L.A. , Posner M.R. , Ruprecht R.M.
Published: March 2003

Simian–human immunodeficiency viruses (SHIV) allow the evaluation of antiviral strategies that target the envelope glycoproteins of the human immunodeficiency virus 1 (HIV‐1) in macaques. We previously protected neonates from oral challenge with cell‐free SHIV‐vpu+ by passive immunization with synergistic human neutralizing monoclonal antibodies (mAbs) (Baba et al., Nat Med 6:200–206, 2000). mAbs were administered prenatally to pregnant dams and postnatally to the neonates. Here, we used solely postnatal or postexposure mAb treatment, thus significantly reducing the amount of mAbs necessary. All neonatal monkeys were also protected with these abbreviated mAb regimens. Our results are directly relevant for humans because we used mAbs that target HIV‐1 envelope glycoproteins. Thus, the large‐scale use of passive immunization with neutralizing mAbs may be feasible in human neonates. The mAbs, being natural human proteins, can be expected to have low toxicity. Passive immunization has promise to prevent intrapartum as well as milk‐borne virus transmission from HIV‐1‐infected women to their infants.
Viral dynamics of early HIV infection in neonatal macaques after oral exposure to HIV‐2287: an animal model with implications for maternal–neonatal HIV transmission
Authors: Herz Arnd M. , Robertson M.N. , Lynch J.B. , Schmidt A. , Rabin M. , Sherbert C. , Agy M.B. , Anderson D. , Hu S‐L , Greenberg P.D. , Morton W.R.
Published: March 2003

A model of vertical HIV transmission was developed using oral HIV‐2287 exposure of newborn Macaca nemestrina. The minimal Animal Infectious Dose for this oral route was found to be 10‐fold higher than that for atraumatic viral transmission across other mucosal membranes (vaginal/rectal) of juvenile macaques. However, once infection was established, viral replication was rapid and plasma viremia could be detected by reverse‐transcriptase polymerase chain reaction and viral co‐culture within 1 week following exposure. No animal was resistant to infection and all macaques initially exposed to a subinfectious viral inoculum were subsequently infected by re‐exposure of mucosal membranes. Higher viral load during primary infection correlated with a more rapid CD4 depletion; however, all HIV‐2287‐infected animals developed CD4 depletion during the observation period. This animal model can now be used to study early viral replication in the presence and absence of anti‐retroviral agents to help identify conditions to reduce vertical HIV transmission in human newborns.
Genetic management of nonhuman primates
Authors: Williams‐Blangero Sarah , VandeBerg John L. , Dyke Bennett
Published: March 2003

Genetic management is widely recognized as a critical component of the overall management of captive nonhuman primate colonies which produce animals for biomedical research. In this paper, we review the roles of conservation‐oriented genetic management, research‐oriented genetic management, genetic management at the level of taxomomic class, genetic management at the level of the population, and quantitative genetic analysis in comprehensive genetic management programs for nonhuman primate colonies. We conclude that genetic management is crucial for maintaining nonhuman primate populations suitable for genetic research on normal and disease‐related phenotypes. In addition, for research programs that do not have specific genetic objectives, genetic management is essential to facilitate the selection of samples of well‐matched unrelated animals for experimental purposes.
Rhesus rhadinovirus infection in healthy and SIV‐infected macaques at Tulane National Primate Research Center
Authors: Ruff K. , Baskin G.B. , Simpson L. , Murphey‐Corb M. , Levy L.S.
Published: March 2003

Rhesus rhadinovirus (RRV) infection was quantified in peripheral blood mononuclear cells (PBMC) from healthy and simian immunodeficiency virus (SIV)‐infected rhesus macaques (Macaca mulatta) at the Tulane National Primate Research Center and in a large collection of simian acquired immunodeficiency syndrome – (SAIDS)‐associated lymphomas. Quantification of RRV load was performed by real‐time PCR using amplification primers specific for the RRV interleukin‐6 homologue (RRV vIL‐6). RRV infection was detected infrequently and at low levels in PBMC of randomly selected healthy animals. Examination of longitudinally collected PBMC from 22 SIV‐infected animals throughout progression to SAIDS revealed similarly low RRV loads that sometimes increased with advancing disease. RRV infection was detected more frequently in the peripheral blood of SIV‐infected animals than in healthy animals. Examination of SAIDS‐associated lymphomas showed that RRV is rare within the tumor mass, likely representing infection in an occasional tumor‐infiltrating cell or contaminating blood. The results indicate that RRV infection in PBMC is not predictive of, and is apparently not required for, development of lymphoma or hyperplastic lymphadenopathy in SIV‐infected animals at TNPRC.
Wear and friction behavior of pressure infiltration cast copper‐carbon composites
Authors: Göller G. , Koty D. P. , Tewari S. N. , Singh M. , Tekin A.
Published: March 2003

Metal matrix composites, prepared by pressure infiltration casting of copper base alloy into 2 types of microporous carbon preforms, one with 100% amorphous carbon and the other containing 40 wt pct. graphite and 60 wt pct. amorphous carbon, have been examined for their wear and friction behavior under ambient conditions using a pin‐on‐plate reciprocating wear tester. Micro‐structural characterization of tribo‐surfaces has been carried out. The thin carbon films formed on the tribo‐surface reduced the friction coefficient and wear for the composites, especially at low loads on the pin. Adhesive wear observed on the tribo‐surface promoted wear and friction at high loads. The wear and friction were observed to be very sensitive to the size and distribution of the microstructural constituents.
The study of iron chlorination from bauxite for its enrichment
Authors: Vračar Rajko Ž. , Vukčević S. M. , Parezanović Ivana S. , Kamberović Željko J.
Published: March 2003

The possibility of enriching bauxite by removing iron in low‐temperature chlorination by gaseous chlorine in the presence of carbon as a reducer from coke and carbon monoxide, is investigated. Thermodynamic analysis points out such a probability. The influence of the working parameters on the chlorination of iron and aluminium was studied in an experimental procedure. The results obtained are in good agreement with the values of Gibbs energies for chlorination. They show that the conditions for process occurrence can be defined with a high degree of iron chlorination from boehmite hematite type (up to 90%) and low chlorination degree of aluminium (2–8%). Kinetic analysis of experimental results indicates that the process mechanism is very complex. Based on the application of corresponding models and calculation of activation energies, it can be concluded that iron chlorination is diffusion controlled.
Experimental studies of the viscosities in the CaO‐FeO‐SiO2‐CaF2 slags
Authors: Shahbazian Fatemeh
Published: March 2003

In this investigation, the viscosity of slags containing 4 components, viz. CaO (4.48 wt% to 35.1wt%), FeO (16wt% to 50.9wt%), SiO2 (27.33 wt% to 47 wt%) and CaF2 (3.53 wt% to 13.2 wt%) were carried out with temperature range 1435 to 1749 K. For measuring the viscosity, a rotating cylinder method with iron spindle and crucible were used. The pre‐ as well as post‐measurement samples of the slags were subjected to chemical and X‐ray fluorescence analyses. The results indicated no significant change in composition during the measurements. In the temperature range of study, CaF2 additions had the expected effect of decreasing the viscosity of the slags. The effect was found to be particularly significant at lower temperatures. The slag viscosities were found to increase with increasing SiO2 contents and decreasing basicities. Arrhenius and Weymann activation energies for viscous flow have been evaluated from the present results.
Effect of Pb in FRHC copper: phase diagram and solidification studies
Authors: Tourón J. L. , Comas C. , Clavaguera‐Mora M. T. , Sirvent N. , Guixà O.
Published: March 2003

Due to its industrial importance, experimental information on the Cu‐O‐Pb‐H system has been revised and a detailed analysis of thermodynamic aspects related to the Cu‐rich part of the system is presented. The solidification path at thermodynamic equilibrium is presented as a function of several casting parameters, and the consequences on the final microstructure of the ingot are analyzed.
Heat capacity of silicon in the range 350–770 K
Authors: Glazov V. M. , Pashinkin A. S. , Mikhailova M. S.
Published: March 2003

The measurements of the specific heat of silicon were carried out using the DSC method. The single‐crystal silicon, containing 5.5×1017 cm−3 of oxygen, was the subject of our study. The measurement error was±5%. The temperature range of the measurements was 350–770 K. The scan rates were 4 or 16 K/min. Slow heating at 4 K/min shows an abnormality in temperature dependence of the heat capacity in the range 550–680 K. The recorded curve resembles a λ‐ shaped curve characteristic of 2nd‐order phase transitions. At a higher scan rate, Cp (T) is a monotonic function, which is identical to the data recommended in reference books. We assumed a possible mechanism of the observed phenomenon. When a crystal of silicon is heated, stressed zones arise along subgrain and domain boundaries due to the anisotropy of thermal expansion. The new high pressure phase of silicon with the structure of white tin (or Si‐II) can be formed in these zones. The appearance releases stress and stops the further growth of precipitates. According to our estimate, the concentration of the newly‐formed phase is about 5 vol.%. Heating at higher rates does not cause similar phenomena.
A study on the purification of diatomite in hydrochloric acid
Authors: Goren Remzi , Baykara Tarik , Marsoglu Muzeyyen
Published: March 2003

This paper describes the purification of diatomaceous earth mined in the Ankara region of Turkey. The diatomaceous earth was found to be essentially amorphous, but a small amount of crystalline illite, K0.7Al2(Si,Al)4O10(OH)2, was present in it. The complete chemical composition of the material was 74.4% SiO2, 14.55% Al2O3, 3.62% Fe2O3, 1.55% CaO, 1.37% MgO, 2.44% K2O and 0.72%Na2O. In connection with the purification of the diatomite, two different processing routes were planned: (i) leaching of the diatomaceous earth directly in cold acidic solutions of HCl; (ii) leaching of the diatomaceous earth directly by using hot 1 and 2 N HCl. It was found that all of the undesirable elements in the composition of the diatomaceous earth were dissolved when treated at about 100°C with acidic solutions prepared using 1 and 2 N HCl for various leaching times. Under several cold acid concentrations, varying from 1 N to 5 N HCl, however, only a small amount of silica is dissolved, while significantly reducing the contribution of undesirable aluminium, calcium, magnesium, iron and alkaline elements.
An investigation of slag floatation and entrapment in a continuous‐casting tundish using fluid‐flow simulations, sampling and physical metallurgy
Authors: Solhed Henrik , Jonsson Lage
Published: March 2003

Some aspects of inclusion behaviour in the tundish have been investigated both theoretically and experimentally. Good agreement was obtained between measured and predicted temperature and flow fields for 1‐ to 6‐strand continuous‐casting tundishes. In this study the flow field was redesigned with weirs, resulting in the addition of a vertical component to Stoke's equation. The results indicate an increase in the velocity that cause a rise of inclusions (smaller inclusions (<20 μm)). Consideration of slag, flux and refractory in the model has also made it possible to simulate the mixing of steel and slag. Special sampling techniques were used to gather information. Samples were analysed using ultrasonic testing, LOM, SEM and Atomic Force Microscopy (AFM). The analysis results were used to verify the predictions regarding steel/slag mixing and understanding of physical conditions at the interfaces. As a result, the casting praxis was improved (cleaner steel) and the products were of higher quality.
Stage‐classified matrix models and age estimates
Authors: Barot Sébastien , Gignoux Jacques , Legendre Stéphane
Published: March 2003

When the size of individuals is a better indicator of their chances to survive, grow, and reproduce than their age, the suitable matrix population model is stage‐classified. Cochran and Ellner developed a method to assess age‐based parameters from such models. We present here, for these age estimates, simplified formulas that are valid whenever there is neither retrogression nor fission: individuals may only die, survive in the same stage, or survive and recruit to the next stage. Our formulas enable one to understand better why, and under which hypotheses, it is possible to compute age estimates from a stage‐classified model, and point out some limitations of the method. These limitations in fact come from the basic hypothesis of stage‐classified matrix models: stage is considered to be the only variable that influences survival and recruitment rates. As a consequence, age estimates using stage‐classified models should be valid if the stages describe precisely enough the life cycles of the studied species, and particularly if senescence is taken into account.
Secondary metabolites in Cladina stellaris in relation to reindeer grazing and thallus nutrient content
Authors: Hyvärinen Marko , Walter Bettina , Koopmann Ricarda
Published: March 2003

We analysed concentrations of phenols and key macro‐nutrients in a dominant mat‐forming lichen, Cladina stellaris, in dry heath forests subjected to heavy reindeer grazing in Finnish Lapland. Lichen samples were collected in the beginning of two growth seasons from six to eight sites with old reindeer exclosures that served as control plots within sites. The concentration of perlatolic acid in lichen apices (top 10 mm) was higher in grazed plots than in control ones, whereas usnic acid did not seem to respond unequivocally to grazing. Moreover, there was a strong negative relationship between nitrogen and phenolic content of Cladina stellaris in intact plots but this relationship was absent in grazed ones. Changes in nitrogen and phosphorus contents caused by reindeer grazing were not correlated with changes in the level of phenolics in lichen thalli. The present result demonstrated that the carbon‐nutrient balance (CNB) hypothesis may well explain some of the variation in lichen phenolic content but is not sufficient for explaining changes caused by reindeer grazing. We hypothesized that physical changes in the lichen microenvironment induced by reindeer have more profound impact on lichen phenolic content than alterations in thallus nutrient content.
Allee effects in stochastic populations
Authors: Dennis Brian
Published: March 2003

The Allee effect, or inverse density dependence at low population sizes, could seriously impact preservation and management of biological populations. The mounting evidence for widespread Allee effects has lately inspired theoretical studies of how Allee effects alter population dynamics. However, the recent mathematical models of Allee effects have been missing another important force prevalent at low population sizes: stochasticity. In this paper, the combination of Allee effects and stochasticity is studied using diffusion processes, a type of general stochastic population model that accommodates both demographic and environmental stochastic fluctuations. Including an Allee effect in a conventional deterministic population model typically produces an unstable equilibrium at a low population size, a critical population level below which extinction is certain. In a stochastic version of such a model, the probability of reaching a lower sizeabefore reaching an upper sizeb, when considered as a function of initial population size, has an inflection point at the underlying deterministic unstable equilibrium. The inflection point represents a threshold in the probabilistic prospects for the population and is independent of the type of stochastic fluctuations in the model. In particular, models containing demographic noise alone (absent Allee effects) do not display this threshold behavior, even though demographic noise is considered an “extinction vortex”. The results in this paper provide a new understanding of the interplay of stochastic and deterministic forces in ecological populations.
Are differences in seed mass among species important in structuring plant communities? Evidence from analyses of spatial and temporal variation in dune‐annual populations
Authors: Coomes David A. , Rees Mark , Grubb Peter J. , Turnbull Lindsay
Published: March 2003

We analyse the population and spatial structures of coastal annual‐plant communities, across ten dunes and three years, to explore the role of seed mass in structuring these communities. One suggestion is that annual‐plant communities are structured by competition‐colonization trade‐offs driven by difference among species in seed‐allocation strategies, while another perspective is that seed mass influences the ways in which species respond to environmental variation. In support of the competition‐colonization trade‐off, the two largest‐seeded species found on the dunes (Erodium cicutarium and Geranium molle) were negatively associated with the other guild members at the 10‐mm scale in 1995, suggesting they locally excluded smaller‐seeded species in that year (when population densities were high). In support of the environmental response hypothesis, populations of annual plants declined between 1995 and 1996 on eight of the ten dunes, underscoring the importance of year‐to‐year environmental fluctuations in determining population sizes. The species that became relatively uncommon also became more aggregated in space, and this effect was most pronounced among the small‐seeded species. Thus, small‐seeded species may be forced to retreat into refuges when conditions are unfavourable, where reduced frequencies of interspecific contacts may increase their chances of persistence. We also show that small‐seeded species sometimes reach much higher population densities than larger‐seeded species, consistent with earlier findings, but reason that this abundance/seed mass relationship could have resulted from either a competition‐colonization trade‐off or from different responses of small‐ and large‐seeded species to environmental variation. We conclude that dune‐annual species with contrasting seed masses respond differently to environmental variation, while the competition‐colonization trade‐off plays a lesser role in community dynamics than previously considered.
Foraging capacities and effects of competitive release on ontogenetic diet shift in bream, Abramis brama
Authors: Persson Anders , Brönmark Christer
Published: March 2003

Bream (Abramis brama) undergo ontogenetic diet shift from zooplankton to benthic macroinvertebrates, but the switching size may be highly variable. To unravel under what conditions bream are pelagic versus benthic foragers, we experimentally determined size‐dependent foraging capacities on three prey types from the planktivory and benthivory niche; zooplankton, visible and buried macroinvertebrates. From these data we derived predictions of size‐dependent diet preferences from estimates of prey value and competitive ability, and tested these predictions on diet data from the field. Planktivorous foraging capacity described a hump‐shaped relationship with bream length that peaked for small bream of 67 mm total length. Benthivory capacity increased with increasing bream size, irrespective if benthic prey were visible on the sediment surface or buried in the sediment. From the experimental data and relationships of metabolic demand we calculated minimum resource requirement for maintenance (MRR) for each of the prey categories used in experiments. MRR increased with bream size for both zooplankton and visible chironomids, but decreased with bream size for buried chironomids, suggesting that intermediate sized bream (120–300 mm) may be competitively sandwiched between small and large bream that are more competitive planktivores and benthivores, respectively. Prey value estimates and competitive abilities qualitatively predicted diet shift in a bream population being released from competition. Competitive release did not change the diet of the largest size‐class feeding on an optimal diet of benthic invertebrates both before and after competitive release. However, profound diet shifts towards benthic macroinvertebrates were recorded for intermediate size‐classes that fed on a suboptimal diet prior to competitive release. Thus, laboratory estimates of size‐dependent foraging capacity of bream in planktivorous and benthivorous feeding niches provided useful information on size‐specific competitive ability, and successfully predicted diet preference in the field.
Bacillary angiomatosis affecting the oral cavity. Report of two cases and review
Authors: Blanc Silvia López , Sambuelli Ruben , Femopase Fabián , Luna Norma , Gravotta Miguel , David Daniel , Bistoni Adriana , Criscuolo Maria Inés
Published: March 2003

Abstract: Bacillary angiomatosis (BA) is an infectious disease characterized by proliferative vascular lesions; it mainly affects HIV‐positive patients. Multiple cutaneous nodular lesions together with fever, chills, malaise, anorexia, vomiting and headache are the most important clinical manifestations. It may also involve the heart, liver, spleen, bones, lung, muscles, lymph nodes, central nervous system and other organs. Erythromycin, 500 mg four times a day, is the drug of choice. The importance of this lesion lies in its clinical and histological similarity with other diseases. Cutaneous and oral lesions of BA clinically resemble Kaposi’s sarcoma (KS). Histopathologically, BA may be confused with angiosarcoma, pyogenic granuloma and epithelioid hemangioma. We report two HIV‐positive men with BA lesions in the oral mucosa. Diagnosis was confirmed by biopsy and Warthin‐Starry silver staining.
Oral pemphigus: long term behaviour and clinical response to treatment with deflazacort in sixteen cases
Authors: Mignogna Michele D. , Muzio Lorenzo , Mignogna Roberto E. , Carbone Roberto , Ruoppo Elvira , Bucci Eduardo
Published: March 2003

Abstract: Systemic corticosteroids remain the mainstay of therapy for pemphigus. Their use has transformed what was almost invariably a fatal illness into one whose mortality is now below 10%. Unfortunately, the high doses and prolonged administration of corticosteroids that are often needed to control the disease result in numerous side effects, many of which are serious or even life‐threatening. Sixteen patients affected by oral pemphigus vulgaris were retrospectively examined to illustrate the natural course of the disease and to describe the efficacy of the treatment we utilised. Deflazacort, used with azathioprine, is the steroid of first choice in our therapeutic protocols, while cyclophosphamide and methylprednisolone “pulse therapy” are reserved for cases unresponsive to high doses of oral corticosteroids. In addition, the literature on oral pemphigus vulgaris was reviewed with respect to clinical history, signs and symptoms, management, and treatment outcome.
Biotypes of oral Candida albicans isolated from AIDS patients and HIV‐free subjects in Thailand
Authors: Teanpaisan R. , Nittayananta W. , Chongsuvivatwong V.
Published: March 2003

Abstract: This study was conducted to examine biotypes and antifungal susceptibility patterns of oral Candida albicans isolated from HIV‐infected patients, HIV‐free patients with candidiasis and healthy subjects. All isolates were biotyped using a typing system based on enzyme profiles, carbohydrate assimilation patterns and boric acid resistance. Thirty‐eight biotypes were found amongst 218 oral C. albicans isolates. The major biotype found was A1S, which accounted for 32.6% of all isolates, and this biotype was the most common in all groups. There was a greater variety of biotypes of C. albicans in the HIV‐infected group than in the other groups; however, there was no statistically significant difference between the groups. The minimum inhibitory concentrations (MICs) of a total of 118 isolates were determined for amphotericin B and for ketoconazole using the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method and the E‐test. When the antifungal susceptibility patterns among the groups were compared, a statistically significant difference was found only with amphotericin B. The median MIC of amphotericin B in the HIV‐infected group was higher than in the healthy group (P=0.013, NCCLS method; P=0.002, E‐test). However, this difference in sensitivity was not restricted to any sub‐type investigated. Our results showed that the biotype patterns of C. albicans isolates that colonize HIV‐infected patients are similar to those of HIV‐free subjects, and there is no relationship between antifungal susceptibility patterns and the biotypes.
Salivary oncofoetal fibronectin and oral squamous cell carcinoma
Authors: Lyons A. J. , Cui N.
Published: March 2003

Abstract: Fibronectin (FN) is a multifunctional adhesive glycoprotein that exists in the extracellular matrix and body fluids. As a result of alternative splicing, extra segments (ED‐A and ED‐B) may be included in the fibronectin molecule. These isoforms of FN, together with FN that has an extra glycosylation (OFFN), are strongly associated with a number of tumours, including oral squamous cell carcinoma (SCC). In view of the likely exfoliation of these cells into the oral cavity from tumours, OFFN might be present in saliva. As such, the presence of OFFN in saliva may be an indicator of oral SCC. The saliva of 12 patients with oral squamous carcinoma and 8 disease‐free individuals was measured for OFFN using an enzyme‐linked immunoassay. Salivary OFFN levels were similar for patients both with oral SCC and those without, suggesting that this would not be a useful test for the detection of oral SCC.
Tooth eruption in a patient with craniometaphyseal dysplasia: case report
Authors: Hayashibara T. , Komura T. , Sobue S. , Ooshima T.
Published: March 2003

Abstract: Craniometaphyseal dysplasia (CMD) is a very rare genetic disorder of bone remodeling caused by osteoclast dysfunction. The clinical and radiographical features of oral findings are presented in a sporadic case of CMD in a child (age 10 years, 7 months). An intraoral examination showed severe malocclusions, including anterior crossbite and deep bite. Furthermore, a radiographic examination showed increased radiopacity of the maxilla and mandibular bones due to hyperostosis and sclerosis of the jaw. There was no root resorption of the canines or molars in the primary dentition, although root formation of the permanent teeth was proceeding. Dental age was calculated to be approximately 1 year, 4 months younger than his chronological age. The eruption speed of the permanent lateral incisors after the gingival emergence was shown to be within normal values, and we discuss whether the canines and premolars in the permanent dentition could erupt or not.
Oral pseudomembranous candidiasis, herpes simplex virus‐1 infection, and oral mucositis in head and neck cancer patients receiving radiotherapy and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) mouthwash
Authors: Nicolatou‐Galitis Ourania , Dardoufas Konstantinos , Markoulatos Panagiotis , Sotiropoulou‐Lontou Anastasia , Kyprianou Konstantinos , Kolitsi Georgia , Pissakas George , Skarleas Christos , Kouloulias Vassilis , Papanicolaou Vassilis , Legakis Nicolaos J. , Velegraki Aristea
Published: March 2003

Abstract: Oral pseudomembranous candidiasis (OPC) was evaluated in 61 patients receiving head and neck radiotherapy (RT). Herpes simplex virus‐1 (HSV‐1) reactivation was also investigated in 14 patients. According to the agreed protocol, granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) mouthwash was administered in 46 patients with radiation‐induced ulcers. Candidiasis was diagnosed in 31 patients. Candida albicans was the most frequent isolate. Multiple Candida species were isolated from the lesions of four patients. Concurrent candidiasis and radiation‐induced ulcers were observed in 17 patients. Viral culture and the polymerase chain reaction disclosed the presence of HSV‐1 in five patients. Twenty of the 46 patients, with initial mucositis grade II and grade III, completed RT with mucositis grade I, indicating a beneficial effect of GM‐CSF mouthwash, although further controlled studies are necessary to verify that. In conclusion, OPC was an important infection in patients undergoing radiotherapy. The role of HSV‐1 in oral mucositis during head and neck radiotherapy needs additional study.
Oral manifestations in HIV‐positive adults from Northern Thailand
Authors: Khongkunthian P. , Grote M. , Isaratanan W. , Piyaworawong S. , Reichart P. A.
Published: March 2003

Abstract: Eighty‐seven HIV‐infected patients in a provincial hospital in Northern Thailand were examined for oral manifestations of HIV disease and AIDS. The median age was 31.3 years. Seventy‐four of the patients were women, 13 were men. 96.6% had a history of heterosexual transmission. Sixty‐one patients were CDC‐category A, 20 were category B and 6 were category C (AIDS). Thirty‐eight percent of the patients revealed oral lesions; 23% had one oral lesion and 13.8% had two oral lesions. Common lesions were oral candidiasis (10.3% pseudomembranous candidiasis, 6.9% erythematous candidiasis and 3.4% both forms), oral hairy leukoplakia (11.5%) and exfoliative cheilitis (6.9%). Gingival linear erythema was seen in 8% of the patients; periodontal lesions and necrotising ulcerative gingivitis were not observed. Men were more commonly affected by oral manifestations than women (P<0.004). The spectrum of oral lesions is comparable to other studies from the region, although most of these reported more men than women. Also, the degree of immunosuppression was more marked (AIDS).
Telomerase activity and telomerase reverse transcriptase (TERT) expression in ameloblastomas
Authors: Kumamoto Hiroyuki , Kinouchi Yoshitaka , Ooya Kiyoshi
Published: March 2003

Abstract: Telomerase activity is believed to be crucial for cell immortalization and cancerization, and is proven to be induced by c‐myc protein. Telomerase reverse transcriptase (TERT) has been recently identified as a catalytic subunit of telomerase, whose expression is closely correlated with telomerase activity. We estimated telomerase activity by the telomeric repeat amplification protocol (TRAP) assay and examined the immunohistochemical expression of TERT and c‐myc protein in 21 ameloblastoma tissues. All ameloblastoma samples were positive for telomerase activity, and TERT expression was detected in the nuclei of neoplastic cells but not in those of stromal cells. Numerous peripheral columnar or cuboidal cells, sporadic central polyhedral cells and some granular cells in ameloblastomas reacted with anti‐TERT antibody. These results suggest that telomerase activity is associated with the oncogenesis or proliferative potential of odontogenic epithelium. The expression of c‐myc protein showed a similar distribution pattern to that of TERT, suggesting that c‐myc protein might induce telomerase activity in ameloblastomas.
Establishment of gingival epithelial cell lines from transgenic mice harboring temperature‐sensitive simian virus 40 large T‐antigen gene
Authors: Hatakeyama S. , Ohara‐Nemoto Y. , Yanai N. , Obinata M. , Hayashi S. , Satoh M.
Published: March 2003

Abstract: We established two gingival epithelial cell lines (GE1 and GE6), originating from transgenic mice harboring the temperature‐sensitive simian virus 40 large T‐antigen gene. GE1 and GE6 grew at a permissive temperature (33°C) in a pavement arrangement and solely formed multilayers that exhibited morphological features similar to those of the stratified oral epithelium, with neither the use of stromal equivalents nor feeder layers. Both GE cells underwent apoptosis at a non‐permissive temperature (39°C). Characteristic keratin peptides, keratin 4 and 13, for mucosal epithelium were obviously expressed in the suprabasal cells, and keratohyalin granules and involucrin were present in the surface flat cells in the multilayered culture. Keratin 10 (one of the markers for higher keratinized gingival epithelium) was rarely found in some uppermost cells, and filaggrin (a component of keratohyalin granules) appeared sparsely in uppermost desquamating cells in the older cultures. These observations indicated that GE1 and GE6 cells exhibited the phenotype characterizing nonkeratinized sulcular epithelium, which possessed the potency undergoing keratinization in such highly stratified cultures as oral gingival epithelium. GE cells increased the expression levels of mRNA of interleukin‐1β and tumor necrosis factor α by the stimulation of lipopolysaccharide and extracellular substances of oral streptococci. The GE cell lines thus could serve as an excellent experimental system for further studies on the physiology of gingival epithelium and corresponding diseases, such as periodontal disease, epithelial hyperplasia, and gingival tumors.
Childhood oral pemphigoid: a case report and review of the literature
Authors: Cheng Yi‐Shing Lisa , Rees Terry D. , Wright John M. , Plemons Jacqueline M.
Published: March 2003

Abstract: Oral pemphigoid, defined as cicatricial pemphigoid limited to the oral cavity, is a clinical subset of cicatricial pemphigoid. Like cicatricial pemphigoid, it occurs mostly in middle‐aged women and it is uncommon in children under 20 years of age. There are 11 cases of childhood cicatricial pemphigoid published previously in the English language literature, and four of them are oral pemphigoid patients. We present a case of the youngest oral pemphigoid patient reported yet. Because of the rareness of cicatricial pemphigoid in children, delayed diagnosis and treatment have been shown in many cases reported earlier. Clinical awareness and early recognition are, therefore, emphasized.
Comparison of HPV infection, p53 mutation and allelic losses in post‐transplant and non‐posttransplant oral squamous cell carcinomas
Authors: Zhang L. , Epstein J. B. , Poh C. F. , Berean K. , Lam W. L. , Zhang X. , Rosin M. P.
Published: March 2003

Background: Oral squamous cell carcinoma (SCC) is increasingly found in transplant recipients, although little is known of the natural history of the disease or the mechanism underlying this increase.

Methods: In this article we describe the history of development of 5 oral post‐transplant SCCs (PSCCs) and compare their genetic profiles to 34 non‐posttransplant SCCs (NPSCCs).

Results: Of the five patients with PSCCs, 3 had bone marrow transplants and two, kidney. All three PSCCs from bone marrow recipients were preceded locally by graft‐vs.‐host disease (GVHD). Two of the GVHD were biopsied and demonstrated dysplasia. Similar frequencies of loss of heterozygosity (LOH) occurred in PSCCs and NPSCCs at 3p, 9p, 17p and 8p, with lower frequencies in PSCCs at 4q (39% vs. 0%), 11q (53% vs. 20%) and 13q (45% vs. 20%), although the latter were not significantly different. Only 1 PSCC had ap53mutation, compared to historical values of 40–60% for NPSCC. Interestingly, human papillomavirus (HPV) DNA was detected in 3 (60%) PSCCs, in comparison to only 4 (12%) of the 34 NPSCCs (P = 0.0346).

Conclusions: Dysplasia in oral GVHD may be a strong indicator of cancer risk and should not be regarded as reactive changes to lichenoid mucosites. The low level ofp53mutation and increased HPV infection support the involvement of HPV in the development of PSCC, while the similarity in LOH patterns suggests that other aspects of carcinogenesis may be comparable in these two types of SCCs.
Co‐existence between oral lesions and opportunistic systemic diseases among HIV‐infected subjects in Thailand
Authors: Nittayananta Wipawee , Chanowanna Nilnara , Winn Than , Silpapojakul Khachornsakdi , Rodklai Amorn , Jaruratanasirikul Sutep , Liewchanpatana Kriengsak
Published: March 2003

Background: The purpose of this study was to determine whether any relationship exists between the occurrence of oral lesions and opportunistic systemic diseases among HIV‐infected subjects.

Methods: A cross‐sectional analytical study was performed in two hundred and seventy‐eight HIV‐infected heterosexual persons and intravenous drug users (IVDUs)(230 males and 48 females, aged 16–65 years, mean 31.9 years). Eighty‐six HIV‐free subjects from the same population were included as controls (61 males and 25 females, aged 17–63 years, mean age 33.1 years). The following information was recorded for each patient: age, gender, risk group and stage of HIV infection, immune status, medication, systemic disease and presence of oral lesions.

Results: Oral candidiasis was the most common oral lesion among HIV‐infected individuals (40%), followed by hairy leukoplakia (HL)(26%). The three most common systemic diseases among the subjects were tuberculosis (TB)(53%), cryptococcosis (14%) andPneumocystis cariniipnuemonia (PCP)(11%). Logistic regression analysis revealed a significant association between the occurrence of TB and the presence of oral candidiasis (OR 2.8; 95% CI 1.6–4.8;P< 0.001), and the occurrence of PCP and the presence of HL (OR 2.2; 95% CI 1.1–4.3;P< 0.001). Positive predictive values of any oral lesions and oral candidiasis in predicting TB were 87% (95% CI 73.0–94.6) and 67% (95% CI 51.9–80.0), respectively.

Conclusions: We concluded that oral candidiasis might be used as a clinical marker for TB, and HL for PCP. Recognition of the lesions by health‐care providers may indicate the need for more intensive clinical and laboratory monitoring and possibly initiation of prophylaxis against these opportunistic systemic infections.
A case of sebaceous carcinoma of the parotid gland
Authors: Siriwardena B. S. M. S. , Tilakaratne W. M. , Rajapakshe R. M. S. K.
Published: March 2003

Sebaceous carcinoma of salivary gland origin is an extremely rare malignancy. It occurs mainly in the parotid gland. This is a case report of a sebaceous carcinoma in a 57‐year‐old woman who had a lump over the right parotid region for 8–9 months. The tumour was composed of small basaloid cells and large foamy cells. Sebaceous differentiation was evident in some tumour islands. This is the first case reported in the Department of Oral Pathology, Faculty of Dental Sciences, University of Peradeniya.