bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct TCR δ repertoires are present in the cutaneous lesions and inflamed duodenum of patients with dermatitis herpetiformis
Authors: Holtmeier Wolfgang , Pfänder Michael , Zollner Thomas M. , Kaufmann Roland , Caspary Wolfgang F.
Published: March 2003

Abstract: Intraepithelial γδ T cells are increased in the inflamed small bowel and are also found in increased numbers in cutaneous lesions from patients with dermatitis herpetiformis (DH). Thus, these cells might play an important role in the pathogenesis of the disease. We investigated the T‐cell receptor (TCR) δ repertoire in involved and non‐involved skin and compared it with the TCR δ repertoire of the inflamed duodenum and peripheral blood of the same patients. An identical TCR δ repertoire in the small bowel and in the cutaneous lesions would suggest a migration of antigen‐specific γδ T cells from the intestine to the skin which cross‐react with cutaneous antigens. T‐cell receptor DV1‐DV3 transcripts were amplified by reverse transcriptase (RT)‐PCR and analyzed by complementarity determining region 3 (CDR3) size spectratyping and nucleotide sequencing. Our results indicate that the cutaneous TCR δ repertoires were oligoclonal and identical dominant γδ T‐cell clones were present in the involved and non‐involved skin. Furthermore, the TCR δ repertoire of the skin was distinct from that in the small bowel. The peripheral blood exhibited a restricted TCR δ repertoire, which differed from that in the intestine and skin. Thus, cutaneous γδ T cells are not specifically expanded within the involved skin and are unlikely to be derived from the inflamed duodenum.
Changes in yellow perch (Perca flavescens) growth associated with the establishment of a walleye (Stizostedion vitreum) population in Canadarago Lake, New York (USA)
Authors: Olson M. H. , Green D. M. , Rudstam L. G.
Published: March 2003

Abstract
–
Piscivorous fish can affect prey growth in two ways: directly by reducing prey density and indirectly by inducing predator‐avoidance behaviors. We investigated these two pathways in yellow perch (Perca flavescens) growth responses to walleye (Stizostedion vitreum) stocking in Canadarago Lake, New York (USA) using a 25‐year time series. Before walleye stocking, yellow perch growth rate was low and independent of body size. As walleye abundance increased, yellow perch growth increased and became size‐dependent. The switch to size‐dependent growth occurred in 1 year, indicating a rapid behavioral response to predators. Mean growth rate increased more gradually and was linearly related to walleye density, indicating a slower numerical effect of walleye on yellow perch densities. Although the net effect was an increase in perch growth, small perch growth initially decreased as walleye became established. Therefore, the combination of numerical and behavioral effects produced a complex pattern of size‐dependent changes in growth of yellow perch.
Nest site selection and aspects of the reproductive biology of the pygmy sculpin (Cottus paulus) in Coldwater Spring, Calhoun County, Alabama
Authors: Johnston C. E.
Published: March 2003

Abstract – Imperiled pygmy sculpins are known from only one locality in Alabama, USA. One conservation strategy for the species is the creation of another population by introducing the species into a suitable habitat. Before such action is considered, however, an understanding of the life history, including reproductive biology and habitat use, of the species must be obtained. In this study, nesting of pygmy sculpins was found to peak in July, although the species has an extended reproductive period. Preferred nesting sites had higher flow and shallower water depth than the surrounding habitat. Pygmy sculpins readily used artificial nest substrates that were introduced into the spring run, where natural nest substrate was uncommon.Note
Temporal food web variability in an upper Missouri River backwater: energy origination points and transfer mechanisms
Authors: Fisher S. J. , Brown M. L. , Willis D. W.
Published: March 2003

Abstract – Energy transfer mechanisms often cannot be identified with either an isotope or a food habits analysis; however, a combined assessment provided collaborative support for depicting backwater food webs. Lateral dimensions in riverine function substantially influence backwater ecology; however, backwater communities are highly dynamic and infrequently investigated due to logistical difficulties. We created seasonal food webs for an upper Missouri River backwater using a combined food habits and stable isotope analysis. Temporal transition of energy origins was apparent. In the spring, carbon primarily originated from sediments, detritus and periphyton. During mid‐summer, carbon was derived from a variety of sources, but included large proportions of terrestrial plants and particulate organic matter. By early fall, the backwater was uncoupled from the river, and autochthonous phytoplankton appeared to be the dominant carbon source. During all sample periods, Chironomidae was an important trophic link conveying energy from the primary producers to the higher consumers. Additionally, zooplankton were an important energy transfer taxa to the abundant age‐0 fish community in the fall, and Corixidae were important in the spring.
Physical activity and behavior of a centrarchid fish, Micropterus salmoides (Lacépède), during spawning
Authors: Cooke S. J. , McKinley R. S. , Philipp D. P.
Published: March 2003

Abstract – The spawning behavior of male and female largemouth bass Micropterus salmoides (Lacépède) was studied in central Illinois during the spring of 1998 to examine patterns of muscular activity associated with different spawning related behaviors and to evaluate whether electromyogram (EMGi) telemetry could be used to detect spawning activity. Fish were implanted with EMGi transmitters (8 females, 16 males) on April 7, prior to the initiation of spawning, and were released in four 0.10‐ha earthen research ponds. Continuous EMGi records, underwater videography and additional visual observations for one pair of EMGi tagged fish were collected throughout the entire spawning event, allowing us to quantify behavioral correlates of physical activity. Male EMGi activity patterns were only correlated with female patterns during courting and periods of male aggression toward the female. Overall, EMGi activity was highest for the female during shuddering (gamete deposition), whereas male EMGi activity was similarly high during periods of nest excavation, shuddering and post‐spawn parental care activities. During spawning, female EMGi activity was positively correlated to shuddering. Average daily EMGi activities for females peaked on the day of spawning. As a result of their engagement in parental care activities, male activity continued to rise even after spawning was completed. EMGi telemetry appears to be a useful technique for monitoring the reproductive activity of largemouth bass, especially in areas of high cover or turbid water or during low light conditions. This technology permitted us to quantify and contrast the activity patterns associated with different spawning related activities, information that will be required to construct accurate, gender‐specific bioenergetics models for this species.
Habitat use and foraging success of 0+ pike (Esox lucius L.) in experimental ponds related to prey fish, water transparency and light intensity
Authors: Skov C. , Berg S. , Jacobsen L. , Jepsen N.
Published: March 2003

Abstract  – This study investigated the habitat use of 0+ pike (9–17 cm) in relation to two different water transparency regimes (clear water/chlorophyll water), two different light regimes (day/night) and the presence/absence of prey using 16 m2 experimental ponds. Pike could freely choose between two structured habitats (a simple structured and a complex structured), an interface habitat (between the structured habitats and open water) and an open water habitat. Foraging success of the pike in relation to water transparency was investigated by comparing mean condition (Fultons K) of the pike as well as the number of surviving prey fish. Habitat use was influenced by the presence/absence of prey and varied between waters with different transparency. The presence of prey intensified the use of structural habitats of 0+ pike in both clear and chlorophyll waters. A preference for complex habitats was found in clear water and was presumably related to foraging. The pike in chlorophyll water, in contrast, appeared more evenly distributed among all habitats, as illustrated by a more intensive use of open water in chlorophyll water compared to the clear water. No detectable impact of water transparency on the foraging success of 0+ pike was found.
The presence of artificial stones predicts the occurrence of the European bullhead (Cottus gobio) in a regulated lowland river in Flanders (Belgium)
Authors: Knaepkens G. , Bruyndoncx L. , Bervoets L. , Eens M.
Published: March 2003

Abstract – In a regulated lowland river in Flanders (northern part of Belgium), the locally endangered bullhead was found mainly near bridges. These locations are characterised by the presence of artificial stones and a relatively high water velocity. To preserve and expand the few remaining bullhead populations, the removal of these stones should be avoided and new suitable habitats should be created.
Micro‐scale distribution of brown trout: an opportunity for kin selection?
Authors: Carlsson J. , Carlsson J. E. L.
Published: March 2003

Abstract – Fourteen microsatellite loci were used to analyse the degree of relatedness between and within cohorts of stream‐living brown trout (Salmo trutta L.). Differences in degree of relatedness were found between cohorts with mature and older having the highest intracohort relatedness. The higher genetic relatedness among the mature and older trout is interpreted as indications of clustering of related mature and older trout prior to spawning in the vicinity of spawning grounds. Young‐of‐the‐year trout showed a lower degree of association with related trout of the same cohort than did mature and older trout. It is argued that the clustering of mature and older trout may facilitate kin selection and that the low degree of association among related young‐of‐the‐year trout could be explained by juvenile fish avoiding competition for territories with related individuals.
A new optimal foraging model predicts habitat use by drift‐feeding stream minnows
Authors: Grossman G. D. , Rincon P. A. , Farr M. D. , Ratajczak R. E.
Published: March 2003

Abstract – There is substantial need for models that accurately predict habitat selection by fishes for purposes ranging from the elaboration of ecological theory to the preservation of biodiversity. We have developed a new and highly tractable optimal foraging model for drift‐feeding fishes that is based on the profitability of occupying varying focal‐point velocities in a stream. The basic model can be written as: Ix = (Ex * Px) = {(D * A * V) * [1/(1 + e(b + cV))]} − Sx, where: (1) Ix is the net energy intake at velocity x; (2) E is prey encounter rate; (3) P is prey capture success rate which can be modelled as 1/(1 + e(b + cV)) where b and c are fitting constants from the prey capture success curve; (4) D is the energy content of prey (J/m3) in the drift; (5) A is the visual reactive area of the fish; (6) V is velocity (cm/s); and (7) S is the cost of maintaining position (J/s). Given that D, A and S can be considered constant over the range of velocities occupied by these fishes, the model reduces to e(b + cV) = 1/(cV − 1) which we solved iteratively to yield an optimal focal‐point velocity for species in each sample. We tested the model by comparing its predictions to the mean focal‐point velocities (i.e. microhabitats) occupied by four species of drift‐feeding minnows in two sites in a stream in North Carolina, USA. The model successfully predicted focal‐point velocities occupied by these species (11 out of 14 cases) in three seasonal samples collected over 2 years at two sites. The unsuccessful predictions still were within 2 cm/s of the 95% confidence intervals of mean velocities occupied by fishes, whereas the overall mean deviation between optimal velocities and mean fish velocities was small (range = 0.9 and 3.3 cm/s for the warpaint shiner and the Tennessee shiner, respectively). Available focal‐point velocities ranged from 0–76 to 0–128 cm/s depending on site and season. Our findings represent one of the more rigorous field tests of an optimal foraging/habitat selection model for aquatic organisms because they encompass multiple species and years, and for one species, multiple sites. Because of the ease of parameterization of our model, it should be readily testable in a range of lotic habitats. If validated in other systems, the model should provide critical habitat information that will aid in the management of riverine systems and improve the performance of a variety of currently used management models (e.g. instream flow incremental methodology (IFIM) and total maximum daily load calculations (TMDL)).
Stable isotope analysis of energy sources for larvae of eight fish species from the Amazon floodplain
Authors: Leite R. G. , Araújo‐Lima C. A. R. M. , Victoria R. L. , Martinelli L. A.
Published: March 2003

Abstract – Aquatic macrophytes form the most productive habitat of the Amazon floodplain and account for more than 60% of the net primary production of the ecosystem. Aquatic grasses are the dominant macrophytes and the main feeding ground of Amazonian larval fish. The present study used stable isotopes of nitrogen and carbon to measure the contribution of aquatic grasses to the production of eight larval fish, and describes the structure of the trophic chain. The carnivore larvae were at the third trophic level, and the detritivores were at the second and third trophic levels. The contribution of aquatic grasses to larval fish production was variable. It could reach a mean value of 25% for three species, but its contribution probably did not exceed 12% in the other five species.
Microgeographical variation in ovum size of the blacktail shiner, Cyprinella venusta Girard, in relation to streamflow
Authors: Machado M. D. , Heins D. C. , Bart H. L.
Published: March 2003

Abstract – There is a strong, positive correlation between egg size and the discharge variable mean annual runoff among populations of Cyprinella venusta Girard from streams in different drainages ranging across the Gulf Coastal Plain of the southern United States. This variation may have resulted from selection for larger egg size, hence larger offspring size, because of greater environmental fluctuation or a greater number of floods in streams with higher runoff. In the present study, we examined C. venusta from populations inhabiting streams varying in mean annual runoff within a single drainage and found a similar correlation between ovum size and runoff. Therefore, the egg size–runoff relationship exists at a much smaller (i.e., intra‐drainage) spatial scale than previous research (based on widespread inter‐drainage variation) has shown. We also attempted to establish a link between mean annual runoff and streamflow‐mediated disturbance as indicated by predictability of streamflow, monthly coefficients of variation in discharge and number of days with extreme low and high flows. Although the overall predictability of discharge did not differ among streams, the streams with high mean annual runoff were characterized by smaller coefficients of variation in winter, fewer days of extremely low flows and a trend toward higher flows in late summer and early fall. At the intra‐drainage scale, higher coefficients of variation did not accurately reflect the numbers of extreme flows. These results call into question the use of coefficients of variation in discharge as indicators of disturbance. Given that eggs, larvae and small juveniles of C. venusta are present in late summer and early fall, when flows in high runoff streams tend to be high relative to low runoff streams, we conclude that these high flows may act as a selective force causing the evolution of larger egg size.
Xylitol‐induced elevated expression of the gbpC gene in a population of Streptococcus mutans cells
Authors: Sato Yutaka , Yamamoto Yasuhito , Kizaki Harutoshi
Published: March 2003

Xylitol possesses a unique property distinct from the other caries‐preventive sweeteners. This sugar alcohol cannot be metabolized to acids but is taken up by Streptococcus mutans and accumulated as a toxic sugar‐phosphate in the cells, resulting in growth inhibition. Due to the accumulation, xylitol induces biological responses including the emergence of xylitol‐insensitive populations. Therefore, we expected another response induced by xylitol and found a new phenomenon, that cells repeatedly cultured in the presence of xylitol evolved into those exhibiting an elevated dextran‐dependent aggregation phenotype. This phenotype was found to result from expression of the gbpC gene, which was previously reported to be expressed only under certain stress conditions. Construction of a Strep. mutans isogenic mutant carrying the gbpC::lacZ fusion gene indicated that gbpC expression of cells repeatedly cultured in the presence of xylitol was elevated 20‐fold. DNA transfer experiments indicated that this phenotypic change did not appear to be due to a mutation. These cells also exhibited decreased adhesion to glass surfaces when grown in the presence of sucrose. This may be one of the ways by which some populations of Strep. mutans are removed from dental plaques.
Cytokine expression in periapical granulation tissue as assessed by immunohistochemistry
Authors: Walker Katie F. , Lappin David F. , Takahashi Keiso , Hope Joyce , Macdonald D. Gordon , Kinane Denis F.
Published: March 2003

The aims of this study were to investigate the expression of pro‐inflammatory, anti‐inflammatory and immune‐related cytokines present in periapical lesions. We investigated the expression of cytokines: namely interleukins IL‐2, IL‐4, IL‐6, IL‐10 and interferon‐γ(IFN‐γ) in formalin‐fixed, paraffin‐embedded sections of periapical granulation tissue. The study samples were biopsies from 24 patients with periapical lesions: 12 with periapical granulomas and 12 patients with radicular cysts. Immunohistochemistry was also performed on tonsillar tissue which served as a control. We utilised a set of specific monoclonal antibodies and polyclonal monospecific antibodies to detect cells that expressed the different cytokines within the tissues. We also considered the nature of the periapical immune response by investigation of the T‐helper 1 (Th‐1) and T‐helper 2 (Th‐2) lymphocyte subsets using their cytokine profile, i.e., Th‐1: IL‐2 and IFN‐γ and Th‐2: IL‐4, IL‐5 and IL‐6. Only a few cells were weakly positive for the IL‐2 protein in each of the tissue sections. Cells that expressed IL‐4 or IL‐6 were far more numerous than cells that expressed either IL‐2 or IFN‐γ. Thus, we demonstrated a greater number of Th‐2 cells in periapical lesions. This relative ratio of the T‐cell subsets underlines the importance of the anti‐inflammatory mechanisms taking place in the diseased tissue manifested by the wide array of IL‐10‐expressing cells: B cells, T suppressor cells (CD8 (+)) and tissue macrophages. The numbers of inflammatory cells expressing the anti‐inflammatory molecules far outnumbered the cells that expressed pro‐inflammatory cytokines. Thus, the downregulation of the inflammatory response and the predominant Th‐2 or humoral immune response in periapical periodontitis may be important features that dictate the outcome of the disease process in the periapical lesion.
Delay of tooth eruption in null mice devoid of the type I IL‐1R gene
Authors: Huang Heguang , Wise Gary E.
Published: March 2003

Interleukin‐one alpha (IL‐1α) is located in the stellate reticulum and its receptor, type I IL‐1R (IL‐1R), is present in the adjacent dental follicle. IL‐1α may play a role in initiating tooth eruption because of its ability to enhance the gene expression in the dental follicle of putative tooth eruption molecules – colony‐stimulating factor‐one (CSF‐1), monocyte chemotactic protein‐1 (MCP‐1), and nuclear factor kappa B (NFκB). To directly examine the effect of IL‐1α and IL‐1R on tooth eruption, we observed the times of tooth eruption in null mice devoid of the type I IL‐1R gene. The results showed that the time of eruption in the null mice was delayed by 2 d for the first mandibular molar and 1 d for incisors as compared to wild type controls. Reverse transcription‐polymerase chain reaction (RT‐PCR) techniques confirmed the absence of the IL‐1R gene in the null mice, but the genes for CSF‐1 and NFκB were still expressed. Thus, a molecule(s) other than IL‐1α also may enhance the expression of CSF‐1 and NFκB in the dental follicle. Because there is a slight delay of tooth eruption in IL‐1R null mice, IL‐1α may normally play a role in eruption. However, eruption eventually can occur without the signaling from IL‐1α.
Effect of lead, cadmium and zinc on the activity of enamel matrix proteinases in vitro
Authors: Gerlach Raquel F. , de Souza Ana Paula , Cury Jaime A. , Line Sérgio R. P.
Published: March 2003

Environmental contamination with heavy metals leads to their uptake by the body. Dental tissues are known to harbor metals in concentrations related to the exposure at the time of dentin or enamel formation. Several enzymes involved in the metabolism of extracellular matrix components have been shown to be inhibited by excess metal ions. Enamel matrix proteinases seem to play a central role in the maturation of dental enamel, and inhibition of these enzymes by metals could interfere with amelogenesis. We have investigated the effect of lead, cadmium and zinc on the activity of enamel matrix proteinases using a colorimetric assay, casein and gelatin zymography, and an assay of enamel protein degradation in vitro. All three metals inhibited the proteolysis, as shown by the three methods employed, in concentrations as low as 110 μM. This study showed that contaminant metals can inhibit proteinolysis when a crude enamel extract containing enamel proteases is tested in vitro. Therefore, the presence of heavy metals in enamel matrix could interfere with amelogenesis due to alteration in normal proteolysis.
Microbiological aspects of an in situ model to study effects of antimicrobial agents on dental plaque ecology
Authors: Giertsen Elin , Guggenheim Bernhard , Thurnheer Thomas , Gmür Rudolf
Published: March 2003

This study validates an in situ model for ecological studies of dental plaque exposed to various antimicrobial agents with different modes of action on plaque bacteria. Eleven subjects wore two acrylic appliances, each containing two bovine enamel discs, during two 1‐wk test periods. Using a split‐mouth crossover design, the appliances were dipped twice daily for 1 min into water (control; treatment A), fluoride (26.3 mM NaF; B), zinc acetate (20.0 mM; C), or fluoride plus zinc acetate (D). Four of the subjects used also chlorhexidine diacetate (2.2 mM; E) and chlorhexidine plus fluoride (F). At the end of each period, plaque was collected from the discs, after which the microbiota were analyzed by culture, automated quantitative immunofluorescence, and a viability fluorescence stain. As compared to control, treatments B, C, and D resulted in a significant reduction of individual taxa as detected by immunofluorescence, whereas similar bacterial viability and total bacterial numbers were observed. In contrast, chlorhexidine significantly reduced bacterial viability, total cell numbers, and the abundance of most of the enumerated taxa. We conclude that this in situ model is well suited to study effects of antimicrobial agents on dental plaque ecology. Combined with viability testing, immunofluorescence is obviously superior to culture in detecting taxa‐specific shifts caused by antimicrobial agents.
Bovine dental papilla‐derived cells immortalized with HPV 18 E6/E7
Authors: Thonemann Birger , Schmalz Gottfried
Published: March 2003

In vitro investigations of cell‐specific metabolism and cell interactions as well as biocompatibility studies are often hampered by the limited lifespan of primary cells originating from target tissues like the oral mucosa, gingiva or pulp. Pulp cells, as do other primary cells, undergo senescence after several passages in vitro. However, senescence can be overcome by transfection of primary cells with oncogenes like the HPV 18 (human papillomavirus 18) E6/E7 oncogene, resulting in immortalized cell lines. The purpose of our study was to establish and preliminary characterize an immortalized bovine dental papilla‐derived cell line by transfection with HPV 18 E6/E7 for future use in biocompatibility testing of dental materials. First passage dental papilla‐derived cells from molar tooth germs of 6‐month‐old calves were transfected by electroporation with pUC18 LCR E6/E7 coding for the HPV 18 E6/E7 oncogene. Cells underwent crisis after 5 wk in culture. Distinct cell colonies arose after about 9 wk. Cells were cloned by single cell dilution in passage 15 and 17. Out of three cell clones maintained in culture, two cell clones showed cell death after 28 and 30 wk, respectively. One cell clone overcame a second crisis after 38 wk and was maintained in culture until passage 75. Stable gene expression of HPV 18 E6/E7 oncogenes was verified by polymerase chain reaction (PCR) and immunohistochemistry. Reverse transcription (RT)‐PCR revealed that the established cell line (passage 50) expresses procollagen type I, alkaline phosphatase and osteocalcin. This suggests that the immortalization with HPV 18 E6/E7 results in a cell line, which maintained phenotypic characteristics of odontoblast‐like cells.
A comparative study on the use of Bio‐Oss® and enamel matrix derivative (Emdogain®) in the treatment of periodontal bone defects
Authors: Pietruska Małgorzata Dorota
Published: March 2003

The aim of the study was to evaluate the clinical and radiographic outcome following two different techniques of periodontal bone defects treatment. The study included 24 generally healthy subjects with advanced periodontitis. The patients were divided into two equal groups, according to the method applied. In the first group, a bovine‐derived hydroxyapatite xenograft (Bio‐Oss®) combined with a resorbable collagen membrane (Bio‐Gide®) was used. The other group was treated with enamel matrix derivative (Emdogain®). Clinical and radiographic examinations were performed prior to and 1 yr after surgery. The following parameters were evaluated: plaque index, gingival index, probing pocket depth, clinical attachment level, gingival recession, radiographic defect depth, and defect width. All clinical and radiographic parameters (except plaque index and gingival recession) were significantly reduced after treatment in both groups. No differences were revealed between the two groups of patients in examined parameters after treatment. The results demonstrated that the treatment of periodontal bone defects with both techniques leads to similar and significant improvements in clinical and radiographic parameters.
Effects of mechanical stimulation on cell cycle duration in rat gingival fibroblast progenitor cells
Authors: Zentner Andrej , Wieschollek Jens H. , Heaney Thomas G.
Published: March 2003

The aim of this investigation was to estimate cell cycle duration in rat gingival fibroblast progenitor cells in steady‐state control and during sustained mechanical stimulation. Elastics (0.15 mm thick) were inserted between maxillary M1 and M2 of 8 wk‐old male rats which were labelled with H3‐TdR and killed in groups of 6–7 animals together with equal‐sized groups of labelled control animals at intervals between 1–168 h. Autoradiographs of consecutive mesio‐distal sections were used to determine grain counts for H3‐TdR‐labelled cells in the connective tissue of the gingival papilla between M2 and M3. Median cell cycle times (MCC) were estimated from plots of mean and median grain counts against time. Under steady‐state conditions, MCC for heavily‐labelled and lightly‐labelled paravascular cell populations and for labelled extravascular cells were 144, 76 and 50 h, respectively. Mechanical stimulation caused a significantly faster rate of reduction of total grain counts relative to controls in all three cell populations and a decline of estimated MCC to 115, 50 and 21 h in heavily labelled and lightly labelled paravascular cells and labelled extravascular cells, respectively. These findings indicate that mechanical stimulation induces faster progression of gingival fibroblast progenitor cells through the cell cycle.
Proteolytic degradation of oral biofilms in vitro and in vivo: potential of proteases originating from Euphausia superba for plaque control
Authors: Hahn Berg I. Cecilia , Kalfas Sotirios , Malmsten Martin , Arnebrant Thomas
Published: March 2003

This paper deals with enzymatic removal of dental plaque, in vitro as well as in vivo, using proteases from the Antarctic krill shrimp (Euphausia superba), referred to as Krillase®. Krillase exhibits both endo‐ and exopeptidase activity but has no microbicidal effect. In model systems with pure cultures of oral microorganisms, Krillase demonstrated inhibition of microbial adhesion to saliva‐coated hydroxyapatite. Furthermore, a protocol for the growth of reproducible in vitro plaque films has been developed, and effects of Krillase on the plaque film were investigated by means of scanning electron microscopy (SEM). The results showed that Krillase efficiently released microorganisms from plaque in vitro, the effect being dependent on the enzymatic activity. The surface energy of the substratum had a minor influence on the formation and removal of plaque in vitro. Ellipsometric studies on the formation and enzymatic removal of a salivary pellicle indicated that the enzymatic effect on plaque may partly depend on degradation of the salivary pellicle. Krillase was also able to remove plaque accumulated on dentures in vivo. Our results demonstrate the potential of Krillase for plaque control, and that these enzymes are worthy of further investigations including clinical studies and work to find a suitable vehicle.
Electron‐microscopic demonstration of proline‐rich proteins, statherin, and histatins in acquired enamel pelliclesin vitro
Authors: Schüpbach P. , Oppenheim F. G. , Lendenmann U. , Lamkin M. S. , Yao Y. , Guggenheim B.
Published: March 2003

Proline‐rich proteins (PRPs), histatins, and statherin are salivary proteins that exhibit high affinities for hydroxyapatite surfaces. In vitro experiments with parotid, submandibular/sublingual or whole saliva have shown these proteins to adsorb selectively to tooth surfaces. This investigation focused on the histo‐morphological identification of PRPs, histatins, and statherin in acquired enamel pellicles. Synthetic hydroxyapatite or bovine enamel were exposed to glandular secretions, and whole saliva and pellicle precursor proteins were identified immunohistologically by electron microscopy. Results obtained by back‐scattered scanning electron microscopy showed these proteins to be present in pellicles. Pellicles displayed a distinct structure consisting of a sponge‐like meshwork of microglobules. Interconnections between structural elements were identified in submandibular/sublingual and whole saliva pellicles only. Transmission electron microscopy of pellicles formed on bovine enamel surfaces revealed a tendency for preferential localization of precursor proteins within the protein film. Since the data showed the presence of pellicle precursors in pellicles derived both from glandular secretions and from whole saliva, it is likely that PRPs, histatins, and statherin are integral components of acquired enamel pellicles in vivo.
Periodontal infections and pre‐term birth: early findings from a cohort of young minority women in New York
Authors: Mitchell‐Lewis Dennis , Engebretson Steven P. , Chen Judy , Lamster Ira B. , Papapanou Panos N.
Published: March 2003

The aim of this report is to provide early data from an ongoing study examining (i) the relationship between periodontal infections and pre‐term low birth weight (PLBW) in a cohort of young, minority, pregnant and post‐partum women; and (ii) the effect of periodontal interventions on pregnancy outcome. During the first 2 yr of the study, 213 women were enrolled and examined clinically for dental plaque, calculus, bleeding on probing, and probing depth. Birth outcome data were available for 164 women, including one group (n=74) subjected to oral prophylaxis during pregnancy, and a second group (n=90) who received no prenatal periodontal treatment. Subgingival plaque samples were available from 145 subjects (4 samples/subject) and were analyzed by checkerboard DNA hybridization with respect to 12 bacterial species. The prevalence of PLBW was 16.5% (27 cases) in this cohort. No differences in clinical periodontal status were observed between PLBW cases and women with normal birth outcome. However, PLBW mothers had significantly higher levels of Bacteroides forsythus and Campylobacter rectus, and consistently elevated counts for the other species examined. PLBW occurred in 18.9% of the women who did not receive periodontal intervention (17 cases), and in 13.5% (10 cases) of those who received such therapy.
Clinical performance of a laser fluorescence device for detection of occlusal caries lesions
Authors: Lussi A. , Megert B. , Longbottom C. , Reich E. , Francescut P.
Published: March 2003

Children and adolescents must be examined often for occlusal caries. Diagnosis of fissure caries is difficult especially when the tooth surface appears seemingly intact. It has been shown that using traditional clinical methods, as little as 20% of teeth with fissure caries under intact surfaces were correctly recognised as such. Therefore, new methods for increasing the accuracy of diagnosis have been sought for years. Recently, a new device, based on fluorescence measurements, was introduced. The purpose of this study was to test the device under in vivo conditions in order to provide recommendations for its use in the dental office. Seven general dental practitioners examined a total of 332 occlusal surfaces in 240 patients. Caries extent was determined for each site after operative intervention (=‘gold standard’). Clinical inspection and analysis of bitewing radiographs exhibited statistically significant lower sensitivities (31–63%) than did the DIAGNOdent device (sensitivity 92%). It is recommended that the laser device is used in the decision‐making process in relation to the diagnosis of occlusal caries as a second opinion in cases of doubt after visual inspection.
Bone morphogenetic protein 4 is involved in cusp formation in molar tooth germ of mice
Authors: Tabata Makoto J. , Fujii Takafumi , Liu Ji‐Guang , Ohmori Tomoharu , Abe Makoto , Wakisaka Satoshi , Iwamoto Masahiro , Kurisu Kojiro
Published: March 2003

In order to clarify the role of BMP4 in the development of the tooth crown, we employed the antisense technique on molar tooth germs removed from the mandibles of embryonic 13.5‐d‐old mice. In the tooth germ explants incubated for 14 d with antisense oligodeoxynucleotide (AS‐ODN) against Bmp4 (a) cusps were not formed, whereas dentin matrix was secreted in the whole region of the crown, (b) inner enamel epithelial (IEE) cells remained in the undifferentiated state in the occlusal region of the crown, though they differentiated in the proximal region (lateral surface region of tooth crown), and (c) insufficient growth of the dental papilla was observed. A 5‐bromo‐2′‐deoxyuridine (BrdU) uptake experiment showed that, although a site‐specific proliferation of IEE cells occurred in the occlusal region in the control explants, it was not found in the AS‐ODN‐treated explants. In the proximal region, however, the proliferation of IEE cells was detected evenly in all explants treated with or without AS‐ODNs. These results suggest that AS‐ODN against Bmp4 inhibited the differentiation and the site‐specific proliferation of IEE cells in the occlusal region of molar tooth germs, resulting in the suppression of cusp formation. Our data thus suggest that BMP4 is involved in cusp formation and differentiation of ameloblasts in the occlusal region of molars.
Edentulousness and oral rehabilitation: experiences from the patients' perspective
Authors: Trulsson Ulrika , Engstrand Per , Berggren Ulf , Nannmark Ulf , Brånemark Per‐Ingvar
Published: March 2003

The psychological effects of tooth loss in the permanent dentition are relatively unknown. Complete edentulousness is a serious life event in terms of readjustment. The aim of the study was to describe the process patients with deteriorating dental status had gone through before treatment with a fixed prosthesis (Brånemark System, Novum), and to describe what living with a fixed prosthesis means to the patients themselves. In‐depth interviews were carried out with 18 patients, and the interviews were transcribed verbatim and analysed in open, axial and selective coding processes according to Grounded Theory. In the analysis, four categories were developed and labelled: ‘alterations in self‐image’, ‘becoming a deviating person’, ‘becoming an uncertain person’ and ‘becoming the person I once was’. ‘Alterations in self‐image’ was identified as the core category and was related to the other three categories. The core category describes the changes in self‐image starting with the subjects' increasingly worsened dental status, followed by a period of them having to live and cope with a denture and, finally, their living with a fixed prosthesis. The motive power for the decision to undergo treatment with a fixed prosthesis seems to be a desire to restore dental status and also to recapture attractiveness, self‐esteem and a positive self‐image.
The Effects of IgG Purified from Women with SLE and Associated Pregnancy Loss on Rat Embryos in Culture
Authors: Matalon S. T. , Shoenfeld Y. , Blank M. , Yacobi S. , Blumenfeld Z. , Ornoy A.
Published: March 2003

Matalon ST, Shoenfeld Y, Blank M, Yacobi S, Blumenfeld Z, Ornoy A. The effects of IgG purified from women with SLE and associated pregnancy loss on rat embryos in culture. AJRI 2002; 48:296–304 © Blackwell Munksgaard, 2002

PROBLEM: Recurrent fetal loss occurs in approximately 1% of women. Autoimmune causes have been suggested as a factor in some of these cases. High rates of intrauterine fetal growth retardation and increased incidence of prematurity is associated with systemic lupus erythematosus (SLE) and the anti‐phospholipid syndrome (APS). Autoantibodies from sera of SLE/APS patients affect reproductive outcome in pregnant mice, as was studied in vivo, where injection of immunoglobulin (Ig)G purified from patients with APS to mice caused fetal resorptions and growth retardation.

METHODS: In order to investigate the direct effect of IgG purified from women with SLE or APS on the growth and viability of embryos, we cultured 11.5‐day old‐rat embryos in their yolk sacs in the presence of IgG purified from SLE and APS patients.

RESULTS: IgG purified from SLE and recurrent pregnancy loss (RPL) patients affected directly the embryo and yolk sac reducing their growth. The purified IgG positive for anti‐cardiolipin/anti‐DNA antibodies reduced yolk sac and embryonic growth more than sera negative for these antibodies.

CONCLUSION: Various antiphospholipid antibodies affect differently the growth and development of the embryo and the placenta.
Antiphospholipid Antibodies and Kininogens in Pathologic Pregnancies: A Review
Authors: SUGI TOSHITAKA , MAKINO TSUNEHISA
Published: March 2003

PROBLEM: Recently, evidence has accumulated for the presence of the kallikrein–kinin system or plasma contact system in the fetoplacental unit. The Kallikrein–kinin system or plasma contact system consists of three essential plasma proteins. These are coagulation factor XII, prekallikrein and high molecular weight kininogen. Deficiencies of these proteins and antiphospholipid antibodies are frequent hemostasis‐related abnormalities found in unexplained recurrent aborters.

METHOD OF STUDY: Review of existing data.

RESULTS: Reports of antiphosphatidylethanolamine antibodies (aPE) with similar or identical pathogenic associations as those described for anticardiolipin antibodies (aCL) are found in the literature. We showed a strong association between recurrent pregnancy losses and aPE, the latter of which recognizes kininogens, and kininogen‐binding proteins, factor XI and prekallikrein. The reports of aPE are reviewed, the function of the kininogens are summarized, and their role in pregnancy is discussed.

CONCLUSIONS: Because kallikrein–kinin system may play an important role in pregnancy especially in fetoplacental unit, disruption of this system may be a risk factor for early gestational losses.
Effect of an Endocrine Disruptor on Mammalian Fertility. Application of Monoclonal Antibodies against Sperm Proteins as Markers for Testing Sperm Damage
Authors: PEKNICOVÁ JANA , KYSELOVÁ VENDULA , BUCKIOVÁ DANA , BOUBELÍK MICHAEL
Published: March 2003

PROBLEM:  To determine the influence of an endocrine disruptor [bisphenol‐A (BPA)] on the integrated reproductive process as well as on individual reproductive organs and gametes in order to select suitable markers for testing sperm damage.

METHOD OF STUDY:  The effect of BPA on fertility in vivo in multigenerational studies in an outbred stock of mice was studied. Damage of reproductive organs was assessed by histochemical methods and damage of spermatozoa by means of a panel of monoclonal antibodies (MoAbs) against intra‐acrosomal sperm proteins.

RESULTS:  BPA had a negative influence on offspring born of mice, on reproductive organs, and on acrosome integrity of mice spermatozoa. Selected MoAbs against intra‐acrosomal mammalian sperm proteins, cross‐reacted with mouse spermatozoa, were used for determination of the acrosome integrity. BPA had no effect on body weight and testicle weight of males.

CONCLUSIONS:  The present results demonstrate that BPA has a negative effect on in vivo fertility of mice, with impact on spermatogenesis and sperm quality. Monoclonal antibodies against intra‐acrosomal sperm proteins can be used for detecting sperm damage.
A Th2 Chemokine, TARC, Produced by Trophoblasts and Endometrial Gland Cells, Regulates the Infiltration of CCR4+ T Lymphocytes into Human Decidua at Early Pregnancy
Authors: TSUDA HIROSHI , MICHIMATA TOSHIHIKO , HAYAKAWA SATOSHI , TANEBE KYOKO , SAKAI MASATOSHI , FUJIMURA MASAKI , MATSUSHIMA KOUJI , SAITO SHIGERU
Published: March 2003

PROBLEM: A chemokine receptor, CCR4 preferentially expressed on type 2 helper T (Th2‐type) cells, and its ligand, thymus and activation regulated chemokine ‐(TARC/CCL)‐ play important roles in the recruitment of Th2‐type cells. We examined the distribution of CCR4 expressing CD4+ and CD8+‐T cells in human decidua at early pregnancy, and localized TARC in the decidual tissue and chorionic tissue.

METHOD OF STUDY: Decidual tissue was obtained by legal abortion. The percentages of CCR4 expressing CD4+ and CD8+‐T cells were analyzed by flow cytometry. Localization of TARC protein was evaluated by immunofluorescence staining. The expression of TARC mRNA in the choriocarcinoma cell line and endometrial cell line was analyzed by reverse transcriptase polymerase chain reaction (RT–PCR).

RESULT: The percentages of CCR4+ cells in CD4+‐T cells and CD8+‐T cells were significantly increased in human early pregnancy decidua compared with those in peripheral blood. An another marker of human Th2 and Tc2 cells, CRTH2 molecules was also expressed on CCR4+CD4+‐T cells and CCR4+CD8+‐T cells. In addition, we found that trophoblasts, uterine epithelial cells and endometrial gland cells produce TARC by immunohistochemical staining and the RT‐PCR method.

CONCLUSION: Our findings imply that TARC secreted in decidua mediates the infiltration of CCR4+ T‐cell migration into the fetomaternal interface, decidua, resulting in the maintenance of pregnancy.
Apoptosis in the Uterus of Mice with Pregnancy Loss
Authors: SAVION S. , LEPSKY E. , ORENSTEIN H. , CARP H. , SHEPSHELOVICH J. , TORCHINSKY A. , FEIN A. , TODER V.
Published: March 2003

PROBLEM: The mechanisms mediating pregnancy loss induced by various agents are far from being understood. Thus, we investigated the possible involvement of one such mechanism, the apoptotic process, in pregnancy loss induced by lipopolysaccharide (LPS) or cyclophosphamide (CP) as well as the associated changes in the apoptosis‐regulating gene products p53 and bcl‐2.

METHOD OF STUDY: Pregnancy loss was induced by LPS or CP on days 9 or 12 of pregnancy, respectively. LPS‐ or CP‐associated apoptosis was assessed by the TdT mediated dUTP‐biotin nick end labeling (TUNEL) method as well as by DNA fragmentation analysis, while p53 or bcl‐2 expression was evaluated by immunohistochemistry.

RESULTS: Lipopolysaccharide treatment initiated a resorption process that was accompanied by the appearance of apoptotic cells in the uterus, which increased in number by 24 hr after treatment. Induction of pregnancy loss with CP resulted in the appearance of some apoptotic cells in the uterus, reaching a peak at 72 hr after treatment. DNA fragmentation analysis revealed a DNA ladder at 24 hr after LPS as well as 72 hr after CP treatment. Immunohistochemical analysis demonstrated a continuous p53 expression in the uterus of LPS‐ or CP‐treated mice, which was somewhat elevated at the peak of the apoptotic process. On the other hand, bcl‐2 expression in LPS‐treated mice could be reciprocally correlated with the apoptotic process, appearing only at its initiation or completion, while in CP‐treated mice it was continuously expressed except for some elevation at the completion of the apoptotic process.

CONCLUSIONS: Our results suggest a possible role for the apoptotic process in mechanisms mediating pregnancy loss and indicate an involvement of p53 and bcl‐2 in its regulation.
Genetic Contribution of the Interleukin‐10 Promoter Polymorphism in Endometriosis Susceptibility
Authors: KITAWAKI JO , OBAYASHI HIROSHI , OHTA MITSUHIRO , KADO NORIKO , ISHIHARA HIROAKI , KOSHIBA HISATO , KUSUKI IZUMI , TSUKAMOTO KATSUMI , HASEGAWA GOJI , NAKAMURA NAOTO , YOSHIKAWA TOSHIKAZU , HONJO HIDEO
Published: March 2003

PROBLEM: Interleukin‐10 (IL‐10) is an important immunomodulatory cytokine. The aim of this study was to investigate whether polymorphisms of the IL‐10 gene promoter polymorphisms may be responsible in part for genetic susceptibility to endometriosis.

METHODS OF STUDY: Polymorphisms at position −1082 and −592 in the IL‐10 promoter region were determined in 196 patients with endometriosis and 160 fertile healthy women by polymerase chain reaction (PCR)‐restriction fragment length polymorphism (RFLP).

RESULTS: There were no statistically significant differences in the genotype and allele frequencies of IL‐10 promoter polymorphism between the endometriosis and control groups. However, when subgrouped according to clinical features, the frequencies of the −592*CC genotype and −592*C allele were significantly increased in patients with autoantibodies to carbonic anhydrase II (anti‐CA II ab) compared with controls.

CONCLUSION: IL‐10 promoter polymorphisms were associated with the production of anti‐CA II ab in patients with endometriosis, suggesting a role in the genetic susceptibility for endometriosis.