bluuebunny/crossref_metadata_2025 huggingface dataset:
Impacts of the swimbladder nematode Anguillicola crassus on Anguilla anguilla: variations in liver and spleen masses
Authors: Lefebvre F. , Mounaix B. , Poizat G. , Crivelli A. J.
Published: February 2004

Variations in the liver and spleen masses of the eel Anguilla anguilla were analysed in relation to the parasite load of Anguillicola crassus at autopsy (current infection by swimbladder lumen worms) and in relation to the severity of damage observed in the swimbladder (a way of assessing the intensity of past infections). None of these measures of parasite pressure were shown to account for variation in the relative liver mass, either when controlling for somatic mass or eel age. In marked contrast, a significant increase in spleen size was revealed in eels harbouring many lumen worms and also in eels with severe damage in the swimbladder. Splenic enlargement was nearly two‐fold higher among severely affected eels (harbouring more than seven lumen parasites and showing severe damage in the swimbladder) than among infection‐free eels (no lumen parasites and no pathological signs in the swimbladder). Several possible hypotheses are reviewed before arguing for an adaptive host response involving the haematological and immunological functions of the spleen. Indeed, among eels with no pathological signs in the swimbladder, the relative spleen mass was positively associated with the mass of lumen parasites, which suggests a hyper‐synthesis of blood cells by the spleen in response to the bloodsucking activity of lumen worms. Nevertheless, among eels with no lumen parasites at autopsy, there was still an increase in spleen size in relation to the severity of the swimbladder damage, which also suggests a hyper‐synthesis of splenic immune cells (lymphocytes and macrophages) in reaction to damaged tissues and particularly to larvae in the swimbladder wall.
Habitat use of 0+ year pike in experimental ponds in relation to cannibalism, zooplankton, water transparency and habitat complexity
Authors: Skov C. , Koed A.
Published: February 2004

Habitat use of 0+ year pike Esox lucius(mean 20–31 mm LT) was evaluated in artificial ponds (surface area = 16 m2) in relation to water transparencies (low and high), habitat complexity (low and high), food availability (zooplankton) and cannibalism (mortality in the ponds). Pike could choose freely between a structured area, an open water area and a structure and open water interface area. Habitat use shifted towards the structured habitat type in the presence of high habitat complexity and low water transparency. Both findings could be explained as a consequence of territorial behaviour. When cannibalism was intense, the proportions of pike using the structures were reduced and the largest pike, and hence the potential cannibals, were found inside the structures. Since the smallest pike were constrained to the unsheltered, and hence probably more hazardous, habitat outside the structures, this study suggests that mortality due to intra‐cohort cannibalism may occur in an indirect as well as a direct way.
Ecology of the whiskered sole in the Sado Estuary, Portugal
Authors: Amaral V. , Cabral H. N.
Published: February 2004

The abundance of the wiskered sole Monochirus hispidus in the Sado Estuary showed a marked seasonal pattern, the highest densities occurred in spring and summer. The density of this species was mainly related, non‐linearly, to depth, water transparency and percentage of gravel, fine sand and mud in the sediment. Monochirus hispidus fed mainly on crustaceans and polychaets. Significant differences were found between the proportions of prey items eaten and total length class; larger fish consumed more decapods and polychaets. The von Bertalanffy growth equation coefficients differed between sexes. The asymptotic length L∞ obtained for females was higher compared to males, while the growth coefficient (K) was higher for males. Individuals with mature gonads were found between March and September, but the main spawning period of M. hispidus in the Sado Estuary was from March to June.
Recovery of wild, juvenile brown trout from stress of flow reduction, electrofishing, handling and transfer from river to an indoor simulated stream channel
Authors: Arnekleiv J. V. , Urke H. A. , Kristensen T. , Halleraker J. H. , Flodmark L. E. W.
Published: February 2004

Stress in wild brown trout Salmo trutta was assessed by sampling blood and measuring the concentrations of plasma cortisol and blood glucose in fish collected by electrofishing and immediately anaesthetized with metomidate. In the River Nidelva, Trondheim, Norway, the resting blood plasma cortisol concentration in the juvenile (0 + year) brown trout was 52 ± 44 nM (mean ± s.d.) in December and 2·3 nM (detection limit) in January. The corresponding blood glucose values were 1·8 ± 0·9 and 1·2 ± 0·2 mM, respectively. After electrofishing, handling and transport to the artificial stream, plasma cortisol and blood glucose levels increased significantly in both experiments. A maximum plasma cortisol level of 239 ± 120 and 71 ± 32 nM and a maximum blood glucose level of 3·9 ± 0·9 and 3·0 ± 0·9 mM were measured in the December and January stream channel experiments after transport, respectively. After introduction to the artificial stream, the blood plasma cortisol level returned to resting values within 24 h in the January stream channel experiment. The blood glucose levels remained at a higher level compared to the reference group throughout the December experiment, while it returned to resting values after 24 h in the January stream channel experiment. The major difference between the December and January experiments was the temperature within the artificial stream, 15–17° C in December and 7–9° C in January. This may have influenced the blood glucose levels. After dewatering of the artificial streambed there was a significant increase in plasma cortisol both in the December and January experiments, and after 24 h the plasma cortisol returned to the resting level in the January experiment. The blood glucose also increased during dewatering, although not significantly.
Chloride cells and pavement cells in gill epithelia of Acipenser naccarii: ultrastructural modifications in seawater‐acclimated specimens
Authors: Carmona R. , García‐Gallego M. , Sanz A. , Domezaín A. , Ostos‐Garrido M. V.
Published: February 2004

Modifications in the chloride (mitochondria‐rich) and pavement cells of the gill epithelia of the Adriatic sturgeon Acipenser naccarii after their transfer under hypertonic environmental conditions (salinity 35) were examined by light and electron microscopy. In contrast to freshwater specimens, seawater‐acclimated fish showed a marked increase in the number and size of chloride cells. Ultrastructural modifications included: presence of a slightly invaginated apical crypt, a darker cytoplasm, a more compact tubular system, a major increase in cisternae from Golgi apparatus stacks and flattened‐out sacs with dilated ends that produced an increase in lateral and basal cell surfaces. All these changes indicated enhanced cellular activity. Pavement cells, which largely covered the chloride cells on the gill filament and lamella, exhibited a complex system of microridges on their apical surface. Typical features included numerous desmosomes that characterized the intercellular junction, and the presence in the apical cytoplasm of bundles of filaments and of electro‐dense vesicles in freshwater fish or clear vesicles in seawater‐acclimated animals.
Regulation of the Human Acute Phase Serum Amyloid A Genes by Tumour Necrosis Factor‐α, Interleukin‐6 and Glucocorticoids in Hepatic and Epithelial Cell Lines
Authors: Thorn C. F. , Lu Z.‐Y. , Whitehead A. S.
Published: February 2004

The major acute‐phase protein serum amyloid A, A‐SAA, is upregulated by a variety of inflammatory stimuli, including cytokines and glucocorticoids (GCs). Elevated systemic concentrations of both A‐SAA and tumour necrosis factor (TNF)‐α are a feature of inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease.

Here, we examine the roles of TNF‐α, interleukin‐6 (IL‐6) and GCs on the transcriptional regulation of the two human A‐SAA genes (SAA1 and SAA2) and show that these stimuli have different effects on the SAA1 and SAA2 promoters in HepG2 hepatoma and KB epithelial cell lines. Both genes are induced modestly by TNF‐α and IL‐6 alone and synergistically by TNF‐α plus IL‐6. The TNF‐driven induction of SAA1, but not that of SAA2, can be enhanced by GCs in both cell lines, whereas GCs alone can upregulate SAA1 only in epithelial cells. The upregulation of both genes by cytokines, and of SAA1 by GCs, is more rapid in epithelial cells than hepatoma cells.

We established that the order in which either cell line was treated with TNF‐α and IL‐6 influenced A‐SAA promoter transcriptional activation. Treatment with TNF‐α followed by IL‐6 resulted in a much greater induction of both A‐SAA genes than treatment with IL‐6 followed by TNF‐α.
Decreased CD4+CD25+ T Cells in Peripheral Blood of Patients with Systemic Lupus Erythematosus
Authors: Liu M.‐F. , Wang C.‐R. , Fung L.‐L. , Wu C.‐R.
Published: February 2004

Recent animal studies have shown that CD4+CD25+ T cells play a crucial role in the suppression of the immune response and that depletion of this subset of T cells might lead to development of autoimmune diseases. The aim of the present study was to investigate the levels of CD4+CD25+ T cells in the peripheral blood of patients with systemic lupus erythematosus (SLE). Ninety‐four SLE patients, 52 patients with rheumatoid arthritis (RA) and 50 age‐ and gender‐matched healthy individuals were enrolled in the study. A flowcytometric method was applied in the measurement of CD4+CD25+ T cells. The results showed that patients with SLE had statistically lower levels of CD4+CD25+ T cells than did normal controls, when expressed as either percentages of peripheral blood mononuclear cells (PBMCs) (mean ± SD, 8.49 ± 6.36 versus 11.11 ± 4.58%, P < 0.05) or absolute cell numbers (98.77 ± 97.52 versus 213.93 ± 104.52 cells/mm3, P < 0.05). In terms of CD25brightCD4+ T cells, defined as having a fluorescence intensity of CD25 expression exceeding 100, SLE patients still had significantly lower levels than did normal controls expressed as percentages of PBMCs (1.76 ± 1.32 versus 3.73 ± 1.30%, P < 0.05). No significant differences could be found between RA patients and normal controls. The overwhelming majority of CD4+CD25+ T cells belonged to CD45RO+ cells and most did not express the CD69 molecule. Although decreased CD4+CD25+ T cells were found in SLE patients, we failed to find a significant correlation between the levels of CD4+CD25+ T cells and disease activities of SLE. To the best of our knowledge, this is the first study to demonstrate that patients with SLE had decreased CD4+CD25+ T cells. However, the exact role of the decreased CD4+CD25+ T cells in the pathogenesis of SLE remains to be elucidated.
Methylated CpG‐Containing Plasmid Activates the Immune System
Authors: Cornélie S. , Poulain‐Godefroy O. , Lund C. , Vendeville C. , Ban E. , Capron M. , Riveau G.
Published: February 2004

Bacterial DNA differs from mammalian DNA by the presence of unmethylated cytosine–phosphate–guanosine (CpG) motifs. The immunostimulatory properties of a DNA vaccine have been suspected to be associated with these motifs. The aim of this study was to assess the inactivation of the immunostimulatory potential of a plasmid after methylation of its CpG motifs. We constructed two identical non‐coding plasmids, and one of these was de novo methylated on its CG sequences. A single administration of recombinant antigen with methylated or unmethylated CpG‐containing plasmid was performed in mice. As expected, only unmethylated CpG‐containing plasmid enhanced the specific immune response. However, a study of in vivo activation of Langerhans' cells and analysis of mRNA synthesis indicated that both the plasmids promoted cell emigration and cytokine induction. These data highlight that a methylated CpG‐containing plasmid is not inert and carries immunomodulatory properties. The results further emphasize the necessity to definitively identify the mode of action of plasmids used for DNA vaccination.
Simple Electrostatic Interaction Mechanisms in the Service of HIV‐1 Pathogenesis
Authors: Krambovitis E. , Zafiropoulos A. , Baritaki S. , Spandidos D. A.
Published: February 2004

The main cell population affected by the human immunodeficiency virus‐1 (HIV‐1) infection belongs to the CD4+ T‐lymphocyte family. Recent convincing evidence indicates that the majority of the cells that die due to HIV‐1 are not actually infected by the virus. Instead, these cells are being led to programmed cell death after the activation of apoptotic mechanisms by the virus or its components. We propose here from accumulated evidence that the virus appears to deregulate the physiological function of these cells during the process of antigen presentation. Ionic interactions between the variable V3 domain of the HIV‐1 coat glycoprotein gp120 and the amino terminal of the chemokine receptor CCR5 play a prominent role in this process, and we speculate that nature has evolved simple electrostatic interaction mechanisms which, coupled to specific recognition systems on the cell surface, can initiate and modulate certain cellular events without the need for specific molecular structures. HIV‐1 utilizes such a mechanism to ensure activation of the target host cell.
Debridement and local application of tetracycline‐loaded fibres in the management of persistent periodontitis: results after 12 months
Authors: Aimetti M. , Romano F. , Torta I. , Cirillo D. , Caposio P. , Romagnoli R.
Published: February 2004

Backgrounds, aims: The aim of our study was to evaluate the clinical, radiological and microbiological response to the local delivery of tetracycline (TE) of sites with persistent periodontal lesions.

Material and Methods: The study was conducted in a split‐mouth design. Nineteen patients with at least four bilateral pockets 4–5 mm and bleeding on probing (BOP) were treated with scaling and root planing (SRP) plus TE fibres (test sites) or with SRP alone (control sites). Clinical and radiological measurements were taken at baseline, 6 months and 12 months post‐operatively. Subgingival plaque samples were collected at baseline, at fibres removal, 6 and 12 months following treatment and analysed by polymerase chain reaction.

Results: Both treatments yielded a statistically significant (p<0.05) reduction of probing depth (2.05 and 1.21 mm), gain of clinical attachment level (1.71 and 0.53 mm) and reduction of BOP scores (23.68% and 57.89%) for TE and SRP groups, respectively, when comparing 12‐month data with baseline. The differences between two groups were significant. The prevalence of Treponema denticola and Bacteroides forsythus decreased after therapy in both groups but only in the test sites Actinobacillus actinomycetemcomitans and Prevotella intermedia were not yield detected. The pathogens could be eliminated from five periodontal pockets by SRP alone, while 21 TE sites were not recolonized at 12 months.

Conclusions: SRP plus TE fibres gave the greatest advantage in the treatment of periodontal persistent lesions at least 12 months following treatment.
Quadrant root planing versus same‐day full‐mouth root planing
Authors: Apatzidou D. A. , Kinane D. F.
Published: February 2004

Objectives: The aim of this study was to determine whether same‐day full‐mouth scaling and root planing (FM‐SRP) and quadrant scaling and root planing (Q‐SRP) resulted in variations in the systemic humoral immune response dynamics (antibody titres and avidity) during active treatment and 3 and 6 months post‐therapy.

Material and Methods: Forty patients with chronic periodontitis were recruited into this study. Subjects were randomised into two groups and received either scaling and root planing quadrant by quadrant at 2‐weekly intervals (Q‐SRP group) or same‐day full‐mouth scaling and root planing (FM‐SRP group). Clinical measurements and serum samples were obtained at baseline and approximately 6 weeks after the last clinical intervention (R1) and 6 months after the initiation of therapy (R2). Furthermore, serum samples were obtained from each patient undergoing therapy (Q‐SRP and FM‐SRP) at 3 bi‐weekly instances so as to determine the short‐term effects of each session of scaling and root planing on the dynamics of the humoral immune response. Serum antibody titre was assayed by enzyme‐linked immunosorbent assay (ELISA) and antibody avidity was measured by thiocyanate dissociation against five putative periodontal pathogens: Porphyromonas gingivalis; Actinobacillus actinomycetemcomitans; Prevotella intermedia; Treponema denticola and Bacteroides forsythus.

Results: Both therapies resulted in similar antibody titre reductions against the majority of the organisms tested and although there was a distinct trend for antibody avidity to increase following therapy, this was not found to be statistically significant, reflecting marked inter‐individual variation. In addition, no evidence emerged from this study to support increased antibody titres following the active phases of both treatment approaches due to an inoculation effect. Nevertheless, significant short‐term increases in antibody avidity to most test bacteria were noted for both treatment strategies.

Conclusion: Both therapies were associated with a reduction in antibody titres and an increase in the binding ability or avidity of antibodies, but there was a marked inter‐subject variability and statistical significance was reached for only some of the test bacteria. No significant differences in the humoral antibody dynamics were found between the two treatment approaches.
Accuracy of probing attachment levels using a CEJ Probe versus traditional probes
Authors: Karpinia K. , Magnusson I. , Gibbs C. , Yang M. C. K.
Published: February 2004

Background: Current interest in the assessment of probing attachment level measurements has been stimulated by recent introduction of novel periodontal probes as well as by the reclassification of periodontal diseases. Clinical attachment level (CAL) is currently the “gold standard” for diagnosing and monitoring periodontal diseases.

Aim: To evaluate the performance of the newly introduced cementoenamel junction (CEJ) Probe in detecting CAL using the CEJ as a fixed reference point, and to compare the CEJ Probe with the Florida Disk Probe and a standard Manual Probe (North Carolina Probe).

Material and Methods: Three examiners probed 12 periodontal patients to determine intra‐ and inter‐consistency of both the probes and the examiners, over a 4‐week time interval. Subjects ranged in age from 22 to 74 years. The experimental design was structured to balance the intra‐ and inter‐examiner consistency at the same site during the two visits.

Results: Using the PROC MIXED of SAS, a strong interaction (p<0.001) between the examiner and probes was found. The consistency of probing (repeatability of measurements) depended upon the type of periodontal probe used as well as the skill (experience) of the examiner. Overall, the CEJ Probe displayed a more consistent performance. The CEJ Probe demonstrated greater intra‐examiner consistency than the Disk Probe for two examiners (p<0.01). The CEJ Probe also showed increased inter‐examiner consistency (p<0.01).

Conclusions: The CEJ Probe has the potential to offer the dental team an efficient, accurate mechanism to chart and monitor attachment level measurements over time. Additional studies, using large numbers of examiners, are needed to assess more clearly the performance of each individual probe.
Effect of a combination of amine/stannous fluoride dentifrice and mouthrinse in periodontal maintenance patients
Authors: Paraskevas S. , Danser M. M. , Timmerman M. F. , Van der Velden U. , Van der Weijden G. A.
Published: February 2004

Aim:The purpose of the present study was to evaluate the beneficial effect of using a dentifrice and mouthrinse containing amine fluoride (AmF) and stannous fluoride (SnF2) in a group of periodontal maintenance patients. Efficacy parameters were plaque, gingival inflammation, pocket depth and attachment loss. An additional parameter was development of stain.

Material and Methods:In total, 80 patients who had been treated for moderate‐to‐severe periodontitis agreed to participate in this study. Subjects received supportive periodontal therapy at regular intervals of 3–4 months for at least a period of 1 year. The patients were randomly divided into two groups: (1) the test group used an AmF/SnF2dentifrice and mouthrinse and (2) the control group used a sodium fluoride (NaF)‐containing dentifrice and mouthrinse. Clinical assessments were performed at baseline, 3, 6, 12, 18 and 24 months.

Results:The mean plaque index score after 3 months in the test group (0.24) was significantly lower than that in control group (0.34) (p0.05), a difference that was maintained throughout the remainder of the study. In terms of bleeding on probing, at no point in time were significant differences between test and control group found. No significant differences were noted between the two groups, nor were there any significant changes in comparison with baseline values with respect to pocket depth and attachment level. At baseline, the mean percentage of sites with no staining was 98% for both the test and control groups. At all further assessments, the staining in both groups was elevated as compared with baseline. Smoking did not affect the outcome of the study.

Conclusion:The combined use of an AmF/SnF2dentifrice and mouthrinse did not affect the parameters of inflammation (bleeding upon marginal probing and probing pocket depth), but it has shown to be more effective in terms of plaque reduction when compared with the use of an NaF dentifrice and mouthrinse in a group of periodontal patients placed under regular maintenance care.
Hertwig's epithelial root sheath, enamel matrix proteins, and initiation of cementogenesis in porcine teeth
Authors: Bosshardt Dieter D. , Nanci Antonio
Published: February 2004

Objectives: The aim of this study was to analyze the association between Hertwig's epithelial root sheath (HERS) cells, enamel matrix proteins (EMPs), and cementogenesis.

Material and Methods: Porcine teeth were examined at the beginning of root formation by light and transmission electron microscopy. Colloidal gold immunocytochemistry was used to analyze the protein expression of amelogenin and ameloblastin.

Results: Before and during disintegration of HERS, its cells displayed the cytologic features of protein synthesis and secretion. While some cells assumed an ameloblast‐like phenotype, others extended their territory away from the root surface. A collagenous matrix filled the widening intercellular spaces, and tonofilaments and desmosomes were still present in cells featuring the morphologic characteristics of cementoblasts. Labeling for amelogenin was observed but ameloblastin was not immunodetected. Labeling was associated with organic matrix deposits that were sporadically and randomly distributed both along the root surface and away from it among the dissipated epithelial cells.

Conclusions: These findings suggest that HERS' cells occasionally assume a lingering ameloblastic activity at the beginning of root formation in the pig. While the results do not support the hypothesis of a causal relationship between EMPs and cementogenesis, they lend support to the concept of an epithelial origin of cementoblasts.
Local biochemical markers of bone turnover: relationship to subsequent density of healing alveolar bone defects
Authors: Reinhardt Richard A. , Sanderfer Van J. , Meinberg Trudy A. , Nummikoski Pirkka , Lee Hsi‐ming , Marx David B.
Published: February 2004

Objectives: This pilot study was designed to test whether biochemical markers of bone turnover in washes of periosteal or trabecular alveolar bone surfaces could be correlated with increases in bone density of an adjacent healing implant socket.

Methods: Ten subjects had a canula inserted into the alveolar crest and sterile phosphate‐buffered saline was washed over the periosteal and trabecular surfaces and collected. Surgical flaps were reflected, 5 mm diameter bone cores were removed from the bone wash site, and standardized radiographs were taken. The sites were allowed to heal for 12 weeks, and radiographs were repeated. Bone washes of the healing sites were also collected after 2 and 12 weeks. Washes were analysed for bone turnover markers osteocalcin (OC; radioimmunoassay) and C‐terminal telopeptide of Type 1 collagen (ICTP; enzyme‐linked immunosorbent assay (ELISA)), and blood component albumin (ALB; ELISA). Changes in bone density during healing were determined by radiographic absorptiometry.

Results: OC/ALB and ICTP/ALB ratios were higher for trabecular than periosteal washes at baseline (p0.01). Trabecular OC/ALB and ICTP/ALB were inversely correlated with increasing bone density of the healing bone core socket (r=−0.72, p=0.03; Pearson's correlation coefficient).

Conclusions: Biochemical markers of bone turnover in bone washes of specific alveolar bone sites may prove helpful in predicting how the bone density will increase around healing dental implants.
Effects of a metal etchant and two primers on resin bonding durability to titanium
Authors: Taira Yohsuke , Yanagida Hiroaki , Matsumura Hideo , Atsuta Mitsuru
Published: February 2004

The purpose of this study was to investigate the efficacy of an etchant in titanium bonding. The aqueous etchant consisted of 0, 5, or 10 wt% ammonium hydrogen fluoride (AHF) in combination with 0, 0.03, 0.3, or 3 wt% cupric chloride (CC). The two primers used were a phosphate‐methacrylate primer and a thiophosphate‐methacrylate primer, and two self‐curing resins (Super‐Bond C&B and MT) were employed as luting agents. Disk specimens were cast with a commercially pure titanium. The surface was air‐abraded with 50 µm alumina, etched for 10 s, rinsed with water, and then air‐dried. The primer was applied to the bonding area (5 mm in diameter), and an acrylic rod was bonded to the specimen with the luting agent. Shear bond strengths were evaluated after 24 h of water storage and following 10 000 thermocycles (4°C and 60°C). The post‐thermocycling bond strength was significantly increased with each of the two primers compared with the unprimed controls. The etchant containing 5 wt% AHF and 0.3 wt% CC further increased their durability, and microscopic observation revealed that innumerable submicron crystals were created on the etched specimen. The present results suggest that the chemical etching improved the resin bonding durability to titanium in combination with the primer used.
Leaching of plasticizers from temporary denture soft lining materials
Authors: Munksgaard Erik Christian
Published: February 2004

The loss of the plasticizers dibutylphthalate, butylphthalylbutyl glycolate, benzylbenzoate, methylsalicylate, and benzylsalicylate from four soft lining materials was measured. A 0.1% aqueous solution of triton X‐100, reduced was used as immersion medium, since the solubility of plasticizer in this medium was close to that of saliva. The loss of plasticizer was monitored up to 30 d after mixing. For two of the materials, the average amount of leached dibutylphthalate within the first day exceeded the proposed tolerable daily intake (TDI) by about 11 and 32 times, respectively, for an average adult person. Similarly, for these two materials, the average daily amount within the first 30 d of leached dibutylphthalate was 2.2 and 6.6 times larger, respectively, than the TDI limit. The cumulative amount leached over 30 d for each of the four materials was 128–253 mg plasticizer g−1. The results indicate the need for further biological evaluations of these products.
Curing efficiency of various types of light‐curing units
Authors: Rahiotis Chris , Kakaboura Afrodite , Loukidis Michalis , Vougiouklakis George
Published: February 2004

This study compared monomer conversion (DC), the per cent linear polymerization shrinkage (%LS), the wall‐to‐wall contraction pattern (per cent of peripheral opening, %DM, and maximal marginal gap, MG) and depth of cure (DOC), of a hybrid resin composite (Spectrum TPH) exposed to different types of light‐curing units and exposure modes (Virtuoso‐PAC, Elipar TriLight‐QTH, and FreeLight‐LED). The QTH and LED units were used in two curing modes: the exponential ramp and the continuous output modes. Monomer conversion was investigated by micro Multiple Internal Reflection (MIR)‐Fourier‐transform infrared (FTIR) spectroscopy and %LS was measured by the deflective disc method. The wall‐to‐wall contraction method used a cylindrical cavity model in extracted human teeth. The per cent debonded margins relative to the cavity periphery (%DM) and the width of maximum gap (MG) was evaluated. The DOC was determined using Vickers microhardness measurements (200 g load, 20 s) at the top surface (H0), at 2 mm (H2) and at 4 mm (H4) depths, and the results expressed as H2/H0 and H4/H0 ratios. Significantly lower %DC and %LS values were provided by PAC and LED units. No differences were found in %DM among the curing units and PAC exhibited the highest MG. No significant differences were noted among light‐curing groups in terms of H2/H0 microhardness values. The QTH, operated in exponential mode, resulted in the highest H4/H0 value. The exponential mode of the QTH demonstrated superior performance for the total of the characteristics evaluated.
Long‐term effects of chemotherapy on orodental structures in children with non‐Hodgkin's lymphoma
Authors: Oğuz Aynur , Çetiner Sedat , Karadeniz Ceyda , Alpaslan Gökhan , Alpaslan Cansu , Pinarli Güçlü
Published: February 2004

The aim of this study was to investigate the late effects of treatment for childhood non‐Hodgkin's lymphomas (NHL) on oral health and dental development. Thirty‐six long‐term survivors that had been treated with chemotherapy of childhood NHL were included in this study and 36 volunteers with similar age and sex distribution served as controls. Both groups underwent a complete orodental examination for decayed, missing and filled teeth and surfaces, gingival and periodontal health according to the Loe–Silness Gingival Index and Sillnes–Loe Plaque Index, enamel defects and discolorations, root malformations, eruption status, agenesis, premature apexifications and microdontia. The severity of these disturbances related to age at the time of NHL diagnosis were also evaluated by creating two groups as < 5 yr and > 5 yr. Although none of the parameters altered with age, patients had significantly higher plaque index, more enamel discolorations and root malformations than did the controls. The results show that long‐term survivors of NHL patients exhibit some orodental disturbances that may be attributed to the chemotherapy regimens.
T‐cell costimulatory capacity of oral and skin epithelial cells in vitro: presence of suppressive activity in supernatants from skin epithelial cell cultures
Authors: Hasséus B. , Jontell M. , Bergenholtz G. , Dahlgren U. I.
Published: February 2004

Oral Langerhans cells (LC) have better T‐cell costimulatory capacity than skin LC. In this study factors affecting this capacity have been assessed in a mixed epithelial cell lymphocyte reaction (MELR) assay. Flow cytometry analysis of freshly recovered cells revealed major histocompatibility complex (MHC) class II molecule expression on 7.5% of the oral epithelial cells and 9.7% of the skin epithelial cells. Monoclonal anti class II antibodies significantly reduced the T‐cell proliferation in the MELR. Pretreatment of skin epithelial cells with interleukin‐1β, tumour necrosis factor‐α or interferon (IFN)‐γ did not affect the MELR proliferation, but incubation with IFNγ significantly suppressed the T‐cell response. Transfer of supernatants from cultures of skin epithelial cells and allogeneic T cells to cultures of oral epithelial cells and T cells resulted in a reduced T‐cell proliferation while supernatants from oral epithelial cells and T cells did not reduce proliferation. The higher proliferation in cultures of T cells and oral epithelial cells than in cultures containing skin epithelial cells may be due to the presence of a suppressive factor in the skin epithelial cell suspensions.
Deranged jaw–neck motor control in whiplash‐associated disorders
Authors: Eriksson Per‐Olof , Zafar Hamayun , Häggman‐Henrikson Birgitta
Published: February 2004

Recent findings of simultaneous and well coordinated head–neck movements during single as well as rhythmic jaw opening–closing tasks has led to the conclusion that ‘functional jaw movements’ are the result of activation of jaw as well as neck muscles, leading to simultaneous movements in the temporomandibular, atlanto‐occipital and cervical spine joints. It can therefore be assumed that disease or injury to any of these joint systems would disturb natural jaw function. To test this hypothesis, amplitudes, temporal coordination, and spatiotemporal consistency of concomitant mandibular and head‐neck movements during single maximal jaw opening‐closing tasks were analysed in 25 individuals suffering from whiplash‐associated disorders (WAD) using optoelectronic movement recording technique. In addition, the relative durations for which the head position was equal to, leading ahead of, or lagging behind the mandibular position during the entire jaw opening‐closing cycle were determined. Compared with healthy individuals, the WAD group showed smaller amplitudes, and changed temporal coordination between mandibular and head‐neck movements. No divergence from healthy individuals was found for the spatiotemporal consistency or for the analysis during the entire jaw opening–closing cycle. These findings in the WAD group of a ‘faulty’, but yet consistent, jaw–neck behavior may reflect a basic importance of linked control of the jaw and neck sensory‐motor systems. In conclusion, the present results suggest that neck injury is associated with deranged control of mandibular and head–neck movements during jaw opening–closing tasks, and therefore might compromise natural jaw function.
Factors influencing the caries decline in Lithuanian adolescents – trends in the period 1993–2001
Authors: Aleksejūnienė Jolanta , Holst Dorthe , Balc̆iūnienė Irena
Published: February 2004

The study aimed to relate a number of factors to the numbers of decayed, missing and filled teeth (DMFT) in 12‐ and 15‐yr‐olds examined and interviewed in 1993 and 2001. A total of 1250 children in 1993 and 935 in 2001 were clinically examined and completed a detailed questionnaire on dental health‐related topics. Factors were related to the DMFT count applying multiple regression analysis. From 1993 to 2001, the mean DMFT decreased approximately 30% in both age cohorts. Despite an observed improvement in dental health in Lithuanian children, the number of Lithuanian children reporting frequent sugar consumption, brushing teeth irregularly and visiting the dentist only in case of emergency was still high compared with Western countries. The DMFT values were related to the fluoride content in the drinking water, oral hygiene, residency and year of examination.
The effects of substratum on the pH response of Streptococcus mutans biofilms and on the susceptibility to 0.2% chlorhexidine
Authors: Deng Dong Mei , Buijs Mark J , Ten Cate Jacob M
Published: February 2004

Antimicrobial agents are now being studied in bacterial biofilms rather than in suspensions. However, no data are available whether the choice of substratum influences biofilm properties or the assessment of antimicrobial efficacy. This study compared dentin and polyacrylate (PA) grooves as substratum for biofilm formation on pH profiles after sugar challenge, as well as biofilm susceptibility to chlorhexidine. Streptococcus mutans biofilms were formed in a constant depth film fermenter (CDFF) by alternate pulsing with sucrose solutions and bacterial growth medium. Spatial and temporal pH profiles were measured using a pH microelectrode outside the CDFF in a flow reactor. Also, 15‐d biofilms were treated with either water or 0.2% chlorhexidine and tested for total viable counts and organic acid content. The results show that in PA grooves, compared with dentin grooves, minimum pH was lower but recovered faster after a sucrose pulse. The pH response to sugar application decreased with the age of the biofilm more in PA than in dentin grooves. Chlorhexidine treatment in PA grooves gave greater reductions in viable counts and acid formation than in dentin. We conclude that the nature of the substratum not only affects metabolic activity of biofilms but also their susceptibility to antimicrobials.
Gingival crevice microbiota from Chinese patients with gingivitis or necrotizing ulcerative gingivitis
Authors: Gmür Rudolf , Wyss Chris , Xue Yi , Thurnheer Thomas , Guggenheim Bernhard
Published: February 2004

The objective of this study was to quantitatively compare the bacterial population structure in plaque from the gingival margin of two groups of 21 Chinese patients with gingivitis or necrotizing ulcerative gingivitis (NUG). Subjects were recruited in four dental clinics in Eastern China. Samples were quantitatively assessed by immunofluorescence and fluorescent in situ hybridization for taxa known to be associated with periodontal diseases. The analyses showed that the fusiform taxa (Fusobacterium nucleatum/Fusobacterium periodonticum, Leptotrichia buccalis, Tannerella forsythensis, and Capnocytophaga sp.), Campylobacter rectus, Prevotella intermedia, Prevotella nigrescens, Selenomonas sputigena, and treponemes were present in both groups with high prevalence. Porphyromonas gingivalis and Actinomyces gerencseriae were much more prevalent in the NUG group. Quantitatively, most taxa, including P. gingivalis, F. nucleatum and the treponemes, accounted, on average, for < 3% of the total bacterial cell number. Only P. intermedia/P. nigrescens, P. gingivalis, S. sputigena, A. gerencseriae, and the sum of all monitored suspected periodontal pathogens were significantly increased in the NUG group. The present study demonstrates for both groups a highly diverse plaque composition and suggests that, etiologically, the overall concentration and the concerted effects of the entire group of opportunistic pathogens thriving in NUG‐associated plaque are of prime importance.
Necrotizing ulcerative gingival lesions and clinical attachment loss
Authors: López Rodrigo , Baelum Vibeke
Published: February 2004

This paper describes the association between the occurrence of necrotizing ulcerative gingival lesions and clinical attachment loss using multivariable logistic regression methods and data originating in an epidemiological study conducted among a random sample of adolescents (n = 9203). Results show that the presence of necrotizing ulcerative gingival lesions is strongly associated with the occurrence of clinical attachment loss, whether defined as the presence of clinical attachment loss  1 mm in at least two teeth or as the presence of clinical attachment loss  3 mm in at least one tooth. This contribution of necrotizing ulcerative gingival lesions appeared to occur independently of the contribution from known common risk factors. Our findings suggest that there are causes of necrotizing ulcerative gingival lesions, yet to be identified, which have a substantial impact on the occurrence of clinical attachment loss.
Efficient discovery of DNA polymorphisms in natural populations by Ecotilling
Authors: Comai Luca , Young Kim , Till Bradley J. , Reynolds Steven H. , Greene Elizabeth A. , Codomo Christine A. , Enns Linda C. , Johnson Jessica E. , Burtner Chris , Odden Anthony R. , Henikoff Steven
Published: February 2004

We have adapted the mutation detection technology used in Targeting Induced Local Lesions in Genomes (TILLING) to the discovery of polymorphisms in natural populations. The genomic DNA of a queried individual is mixed with a reference DNA and used to amplify a target 1‐kbp region of DNA with asymmetrically labeled fluorescent primers. After heating and annealing, heteroduplexes are nicked at mismatched sites by the endonuclease CEL I and cut strands are visualized using Li‐cor gel analyzers. Putative polymorphisms detected in one fluorescence channel can be verified by appearance of the opposite cut strand in the other channel. We demonstrated the efficiency of this technology, called Ecotilling, by the discovery in 150+ individuals of 55 haplotypes in five genes, ranging from sequences differing by a single nucleotide polymorphism to those representing complex haplotypes. The discovered polymorphisms were confirmed by sequencing and included base‐pair changes, small insertions and deletions, and variation in microsatellite repeat number. Ecotilling allows the rapid detection of variation in many individuals and is cost effective because only one individual for each haplotype needs to be sequenced. The technology is applicable to any organism including those that are heterozygous and polyploid.
DVL, a novel class of small polypeptides: overexpression alters Arabidopsis development
Authors: Wen Jiangqi , Lease Kevin A. , Walker John C.
Published: February 2004

Small polypeptides can act as important regulatory molecules that coordinate cellular responses required for differentiation, growth, and development. In a gain‐of‐function genetic screen for genes that influence fruit development in Arabidopsis, we identified a novel gene –DEVIL1 (DVL1) – encoding a small protein. Overexpression of DVL1 results in pleiotropic phenotypes featured by shortened stature, rounder rosette leaves, clustered inflorescences, shortened pedicles, and siliques with pronged tips. cDNA analysis indicates that DVL1 has a 153‐nucleotide (nt) open‐reading frame (ORF) encoding a 51‐amino acid polypeptide that shares no significant similarity to previously identified proteins. Sequence alignment shows that DVL1 belongs to a family of related genes that are limited to angiosperm plants. Ectopic overexpression of each of the five closely related Arabidopsis DVL genes causes similar phenotypic changes, suggesting overlapping function in the DVL gene family. Point mutations of conserved amino acids in the C‐terminal region of the DVL1 polypeptide reveal that these conserved residues are required for DVL1‐overexpression phenotypes. Our results show that the DVL family is a novel class of small polypeptides and the overexpression phenotypes suggest that these polypeptides may have a role in plant development.
FIE and CURLY LEAF polycomb proteins interact in the regulation of homeobox gene expression during sporophyte development
Authors: Katz Aviva , Oliva Moran , Mosquna Assaf , Hakim Ofir , Ohad Nir
Published: February 2004

The Arabidopsis FERTILIZATION‐INDEPENDENT ENDOSPERM (FIE) polycomb group (PcG) protein, a WD40 homologue of Drosophila extra sex comb (ESC), regulates endosperm and embryo development and represses flowering during embryo and seedling development. As fie alleles are not transmitted maternally, homozygous mutant plants cannot be obtained. To study FIE function during the entire plant life cycle, we used Arabidopsis FIE co‐suppressed plants. Low FIE level in these plants produced dramatic morphological aberrations, including loss of apical dominance, curled leaves, early flowering and homeotic conversion of leaves, flower organs and ovules into carpel‐like structures. These morphological aberrations are similar to those exhibited by plants overexpressing AGAMOUS (AG) or CURLY LEAF (clf) mutants. Furthermore, the aberrant leaf morphology of FIE‐silenced and clf plants correlates with de‐repression of the class I KNOTTED‐like homeobox (KNOX) genes including KNOTTED‐like from Arabidopsis thaliana 2 (KNAT2) and SHOOTMERISTEMLESS (STM), whereas BREVIPEDICELLUS (BP) was upregulated in FIE‐silenced plants, but not in the clf mutant. Thus, FIE is essential for the control of shoot and leaf development. Yeast two‐hybrid and pull‐down assays demonstrate that FIE interacts with CLF. Collectively, the morphological characteristics, together with the molecular and biochemical data presented in this work, strongly suggest that in plants, as in mammals and insects, PcG proteins control expression of homeobox genes. Our findings demonstrate that the versatility of the plant FIE function, which is derived from association with different SET (SU (VAR)3‐9, E (Z), Trithorax) domain PcG proteins, results in differential regulation of gene expression throughout the plant life cycle.
The Dof domain, a zinc finger DNA‐binding domain conserved only in higher plants, truly functions as a Cys2/Cys2 Zn finger domain
Authors: Umemura Yoshimi , Ishiduka Tomoko , Yamamoto Rie , Esaka Muneharu
Published: February 2004

The Dof (DNA‐binding with one finger) proteins are plant transcription factors that have a highly conserved DNA‐binding domain, called the Dof domain. The Dof domain, which is composed of 52 amino acid residues, is similar to the Cys2/Cys2 zinc finger DNA‐binding domain of GATA1 and steroid hormone receptors, but has a longer putative loop than that in the case of these zinc finger domains. The DNA‐binding function of ascorbate oxidase gene binding protein (AOBP), a Dof protein, was investigated by gel retardation analysis. When Cys was replaced by His, the Dof domain could not function as a Cys3/His‐ or a Cys2/His2‐type zinc finger. The characteristic longer loop was essential for DNA‐binding activity. Furthermore, heavy metals such as Co(II), Ni(II), Cd(II), Cu(II), Hg(II), Fe(II), and Fe(III) inhibited the DNA‐binding activity of the Dof domain. Manganese ion as well as zinc ion was coordinated by the Dof domain in vitro. On the other hand, the analysis using inductively coupled argon plasma mass spectrometry (ICP‐MS) showed that the Dof domain contained zinc ion but not manganese ion. Thus, the Dof domain was proved to function as a Cys2/Cys2 zinc finger domain.
The irregular xylem 2 mutant is an allele of korrigan that affects the secondary cell wall of Arabidopsis thaliana
Authors: Szyjanowicz Pio M. J. , McKinnon Iain , Taylor Neil G. , Gardiner John , Jarvis Mike C. , Turner Simon R.
Published: February 2004

The irregular xylem 2 (irx2) mutant of Arabidopsis thaliana exhibits a cellulose deficiency in the secondary cell wall, which is brought about by a point mutation in the KORRIGAN (KOR) β,1‐4 endoglucanase (β,1‐4 EGase) gene. Measurement of the total crystalline cellulose in the inflorescence stem indicates that the irx2 mutant contains approximately 30% of the level present in the wild type (WT). Fourier–Transform Infra Red (FTIR) analysis, however, indicates that there is no decrease in cellulose in primary cell walls of the cortical and epidermal cells of the stem. KOR expression is correlated with cellulose synthesis and is highly expressed in cells synthesising a secondary cell wall. Co‐precipitation experiments, using either an epitope‐tagged form of KOR or IRX3 (AtCesA7), suggest that KOR is not an integral part of the cellulose synthase complex. These data are supported by immunolocalisation of KOR that suggests that KOR does not localise to sites of secondary cell wall deposition in the developing xylem. The defect in irx2 plant is consistent with a role for KOR in the later stages of secondary cell wall formation, suggesting a role in processing of the growing microfibrils or release of the cellulose synthase complex.