bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural Study of Pneumocystis carinii in Explant Cultures of Rabbit Lung and in Cultures with and without Feeder Cells
Authors: DEI‐CAS EDUARDO , SOULEZ BENOIT , CAMUS DANIEL , YVATTEZ A. , HERBALT J. 
Published: August 2010

ABSTRACTPneumocystis carinii‐parasitizcd lung explains were obtained from corticoid‐lreated rabbits and maintained in vilro. Twenty‐one days after the beginning of explant cultures, the ullrastructura! morphology of trophozoite, precyst and cyst forms was normal as compared to the in vivo ui‐trastrucuirc of P. carinii from infected rabbit. However, after the 36th day, only altered forms of P. carinii were observed. Lung tissue showed only minor alterations. fntracytoplasmic lamellar inclusions were observed in type 2 alveolar cells from which they were released. While the total number of parasites increased approximately 4‐fold from day 0 to day 41, trophozoite counts increased approximately 6 times. Pneumocystis cells from inocula and supcmaics of cultures with and without Vera cells showed important ullrastructural alterations.
Cytidine Analogues and Stomatogenic Recovery in Amicronucleate Paramecium tetraurelia and Paramecium jenningsi
Authors: NG STEPHEN F. 
Published: August 2010

ABSTRACTRemoval of the micronuclei of Paramecium tetraurelia and Paramecium jenningsi by micropipetting generates amicronucleate cell lines. These cell lines go through a period of growth depression for several dozen fissions, but they gradually recover. Amicronucleate cells in the depression period characteristically exhibit abnormal oral development, particularly reduction in the length of the buccal cavity and an abnormal pattern of the oral membranelles. To test the notion that the macronucleus is involved in the recovery of amicronucleate cell lines, DNA demethylation drugs were administered to amicronucleates in the depression period. After at least 4 fissions, the treated amicronucleates were assessed for their progress in recovery by scoring the proportion of cells with normal oral membranelles. Cvtidine analogues which demethylate cytosine specifically at the 5 position, namely 5‐azacytidine, 5‐aza‐2′‐ deoxycytidine and 5‐fluoro‐2′‐deoxycytidine. promoted recovery of the amicronucleates. Cytidine, 6‐azacytidine, 2′‐fluoro‐2′‐deoxy‐cytidine and cytosine‐β‐D‐arabinofuranoside did not. These results suggest that (i) 5‐methylcytosine is present in the macronucleus of these Paramecium species, probably in small amounts and (ii) recovery of amicronucleates involves demethylation of macronuclear DNA. This implies that in normal cells the micronuclei are involved in maintaining the macronuclear DNA in a methylated state and hence the inactivation of the macronuclear sequences that are to be employed for stomatogenic recovery. A general mechanism for the control of gene expression may therefore be employed for the regulation of specific sequences.
Evidence for Hymenostome Affinities in an Apostome Ciliate
Authors: BRADBURY PHYLLIS CLARKE 
Published: August 2010

ABSTRACTThe functional mouth of exuviotrophic apostome ciltates appears only after an elaborate metamorphosis that begins at the onset of the molting of their crustacean hosts. In the tomite. a non‐feeding migratory stage, a mid‐ventrai depression at the origin of kineties x, y and z has been misidentified as the cytostome. Studies of fine structure and morphogenesis identify the true but nonfunctional cytostome—the subapiral lateral canal —and the falciform and ogival fields as the adoral ciliature. The anterior row of barren kinetosomes that parallels on the right the anterior third of the lateral canal is actually the infraciliature of a paroral. 2 rows of barren staggered kinetosomes. The canal itself is a narrow tube, its walls partially lined with microtubules. It begins 2–3 μm from the apex of the body and passes between falciform field 9 and the ogival field to end near the end of the ogival field. The fine structure of the infraciliature of the falciform and ogival fields differs markedly from that of the somatic kineties. In the host's early pre‐molt stages, the paroral migrates across the ventral surface of the encysted phoront and is accompanied by the microtubules of the lateral canal. The anterior end of falciform field 9 disorganizes into scattered kinetosomes, the trophont's anterior field of kinetosomes, but the posterior end migrates in an arc across the anterior ventral surface and remains as kinety a located near the angle where kinety 1 sharply par ra continues posteriad ind dorsad to the posterior limit of the extended cytostome. At the end of metamorphosis it sinks into The cytoplasm and disappears. The completion of the extended cytostome, the functional mouth, marks the termination of the microstome‐macrostome transformation. The fine structure of the infraciliature and microtubular elements making up the macrostome and the evocation of the microstome‐macrostome transformation in the presence of specific foods suggest that apostome ciliates any more properly be a suborder of Hymenostomatida rather than a subclass of Oligohymenophorea.
Comparison of Intraoral and Percutaneous Approaches for Infraorbital Nerve Block
Authors: Lynch Michael T. , Syverud Scott A. , Schwab Robert A. , Jenkins J. Matthew , Edlich Richard 
Published: August 2010

ABSTRACT Objective: The infraorbital nerve block is frequently used during repair of facial lacerations; both percutaneous and intraoral approaches are used. The authors compared the two techniques for pain of administration and anesthetic effectiveness. Methods: A prospective, randomized, single‐blind, crossover study was conducted using 12 healthy volunteers, aged 25–41 years. No patient had prior experience with infraorbital nerve anesthesia, lidocaine allergy, active oral/facial infection, or previous facial fractures. Bilateral infraorbital nerve blocks were done using the intraoral technique on one side and the percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27‐gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Pain of injection, anesthetic efficacy (anesthesia of upper lip), time to anesthetic onset, and duration of anesthesia were evaluated. Results: By visual‐analog pain scale scores, there was less pain by the intraoral approach, although this difference did not achieve significance (p = 0.08). Overall, nine of the 12 subjects considered the intraoral technique less painful than the percutaneous approach (p = 0.14). The intraoral approach produced upper‐lip anesthesia in 12 of 12 subjects, versus nine of 12 for the percutaneous technique (p = 0.25) The duration of anesthesia was longer with the intraoral approach (1.6 ± 0.8 hours versus 0.9 ± 0.4 hours) than with the percutaneous approach (p = 0.04). The two techniques were similar in times to anesthetic onset. Conclusion: The intraoral approach to the infraorbital nerve block after adjunctive topical anesthesia appeared at least as effective in producing upper‐lip anesthesia as the percutaneous approach without adjunctive topical anesthesia. Although the volunteers subjectively preferred the intraoral approach and visual‐analog pain scores were lower for this approach, these differences did not achieve statistical significance. The intraoral approach was associated with a longer duration of upper‐lip anesthesia.
Substance loss caused by scaling with different sonic scaler inserts – an in vitro study
Authors: Kocher Thomas , Fanghänel Jutta , Sawaf Hassem , Litz Rüdiger 
Published: August 2010

AbstractBackground, aims: Depending on the phase of periodontal treatment, power‐driven inserts with different power levels are necessary: during initial treatment and flap operations, it must be possible to remove calculus which firmly adheres to the root surface with great efficiency; in contrast, gentle root‐surface instrumentation has a high priority during maintenance treatment. Recently, modified sonic scaler inserts have been introduced: diamond‐coated inserts for open flap operations and slim probe‐shaped sonic scaler inserts for deplaqueing during maintenance.Method: We compared the substance removal by these inserts to that of a conventional insert. In a bench system which allows application force, stroke height, and width and frequency of instrumentation to be monitored and also permits assessment of the topography before and after instrumentation (yielding depth removal and removed volume), we instrumented aluminum rods in triplicate and bovine roots in a 5‐fold repetition.Results: With high application forces (1.0 N), the diamond‐coated inserts removed 30 to 50% more substance than the conventional one. Except for the slim inserts, there was a significant linear relationship between increasing force and removed volume. Probe‐shaped inserts do not remove considerable substance even with increasing pressures.Conclusions: Diamond‐coated inserts remove tooth substance very effectively and must thus be handled with care: more pressure effects more removal. Probe‐shaped inserts can be used without risk during maintenance visits.
The reproducibility of methods of assessment for cervical dentine hypersensitivity
Authors: Ide M. , Wilson R. F. , Ashley F. P. 
Published: August 2010

AbstractBackground: Many agents and toothpaste formulations have been proposed for treatment of dentine hypersensitivity. However, studies have reported equivocal or contradictory results, potentially related to a lack of clinical efficacy for agents being tested, poor study design or the use of assessment techniques which are unable to distinguish longitudinal changes in dentine hypersensitivity.Aim: To investigate the reproducibility of commonly used measurement protocols for dentine hypersensitivity on single or multiple teeth. In addition, newly‐developed controlled air and cold fluid stimuli were investigated.Methods and Materials: Standardised pain stimulation techniques were used in 2 investigations with 63 and 42 subjects, respectively. The reproducibility of perceived hypersensitivity before and following stimulation was recorded over time periods of 14 and 2 days, respectively, using visual analogue scales and threshold techniques.Results: Subject demographics resembled those reported in other hypersensitivity investigations. Analysis using several measures of reproducibility indicated that subject‐based reproducibility was limited, even when the stimuli were standardised. However, the data are consistent with the findings of investigations on pain assessment in other fields.Conclusions: The reproducibility of subjects in clinical trials of dentine hypersensitivity may therefore contribute to difficulties in establishing treatment efficacy of agents in clinical trials.
Microassay for the detection of elastase activity in the gingival crevice
Authors: Herrmann Jens Martin , Gonzáles José Roberto , Boedeker Rolf Hasso , Vonholdt Julia , Meyle Joerg 
Published: August 2010

AbstractBackground, aims: A new microassay for the detection of elastase activity (EA) in gingival crevicular fluid (GCF) has been established. GCF was collected with Periopaper® strips and quantified in a Periotron®.Methods: Enzyme activity was measured in a microtiter plate reader, using a fluorometric assay. To ensure quality and precision of the assay, recovery rates were determined at different activities with a recovery of >90%. In a 2nd step, stability of the enzyme was investigated during storage at room temperature, +4 °C, −22 °C, −88 °C. GCF samples retained elastase activity of almost 100% after a storage of 3 days at −22 °C. In a group of 12 healthy volunteers, elastase activity was assayed throughout an 18 day experimental gingivitis protocol.Results: Median activity increased from 481 μU/μl at baseline to 1444 μU/μl at day 18, which was accompanied by the development of the signs of gingivitis. The increase of EA during the experimental phase of the study was highly significant (p<0.001) and correlated well with the increasing severity of gingivitis.Conclusion: The data suggest that elastase activity in GCF is an excellent quantitative measure of gingival inflammation.
The effect of toothpaste on the propensity of chlorhexidine and cetyl pyridinium chloride to produce staining in vitro: a possible predictor of inactivation
Authors: Sheen S. , Owens J. , Addy M. 
Published: August 2010

AbstractBackground/aims: Cationic antiseptics such as chlorhexidine (CHX) and cetyl pyridinium chloride (CPC) interact with dietary chromogens to produce extrinsic stain, and this can be used as a measure of activity of products. The aim of these studies in vitro was to determine if toothpaste influenced the tea staining effects of CHX and CPC as a predictor of action in vivo.Method: Clear acrylic specimens were soaked in pooled human saliva followed by sequential 2‐min soaks in pairs of agents, namely 0.05% CHX, 0.05% CPC, 0.2% CHX, water (W) and toothpaste slurry (TP). The combinations were; TP/CHX, CHX/TP, TP/CPC, CPC/TP, W/CHX, CHX/W, W/CPC, CPC/W, TP/W, W/TP, W/W. These treatments were followed by a 60 min soak in tea. Optical density readings were taken at baseline and after each of 8 cycles.Results: In the separate CHX and CPC studies by comparison with W/CHX, TP/0.05% CHX had little effect on staining, but TP/0.2% CHX showed a reduction in staining of 18%. 0.05% CHX/TP reduced staining by >40%, and 0.2% CHX by >78%. TP/CPC reduced staining by >26% and CPC/TP by 80%. Water after 0.2% CHX, 0.05% CHX and CPC reduced staining by 18%, 13% and 17% respectively. Little staining was seen with TP and W combinations. The data for CHX are in agreement with a study in vivo except TP followed by CHX reduced the activity of CHX.Conclusion: Toothpaste appears to adversely affect the activity of CHX and CPC particularly if used immediately after the antiseptics. The data further supports the concept of separating the use of antiseptics until sometime after the use of toothpaste, and the idea of developing mouthwash friendly toothpastes.
The influence of margins of restorations on the periodontal tissues over 26 years
Authors: Schätzle Marc , Lang Niklaus P. , Ånerud Åge , Boysen Hans , Bürgin Walter , Löe Harald 
Published: August 2010

AbstractAim: The purpose of this investigation was to examine the long‐term relationship between dental restorations and periodontal health.Material and Methods: The data derived from a 26‐year longitudinal study of a group of Scandinavian middle‐class males characterized by good to moderate oral hygiene and regular dental check‐ups. At each of 7 examinations between 1969 and 1995, the mesial and buccal surfaces were scored for dental, restorative and periodontal parameters. The mesial sites of premolars and molars of 160 participants were observed during 26 years (1969–1995). A control group with 615 sound surfaces or filling margins located more than 1 mm from the gingival margin in all 7 surveys was compared with a test cohort with 98 surfaces which were sound or had filling margins located more than 1 mm from the gingival margin at baseline (1969) and had a subgingival filling margin 2 years after (1971).Results and conclusions: The study confirmed the long held concept that restorations placed below the gingival margin are detrimental to gingival and periodontal health. In addition, this study suggests that the increased loss of attachment found in teeth with subgingival restorations started slowly and could be detected clinically 1 to 3 years after the fabrication and placement of the restorations. A subsequent “burn‐out” effect was suggested.
Orthodontic movement in bone defects augmented with Bio‐Oss®
Authors: Araújo M. G. , Carmagnola D. , Berglundh T. , Thilander B. , Lindhe J. 
Published: August 2010

AbstractObjective: To study if it was possible to move, by orthodontic means, a tooth into an area of the jaw that had been augmented with Bio‐Oss®.Material and Methods: 5 beagle dogs were used. The 1st, 2nd, and 4th mandibular premolars on each side were removed. The defect at the left 4th premolar site was filled with a biomaterial (Bio‐Oss®) while the corresponding defect in the right side was left for spontaneous healing. 3 months later, an orthodontic device was inserted in each side of the mandible. The device was designed to allow distal, bodily movement of the 3rd premolars. When the experimental teeth had been moved into the extraction sites of the 4th premolars, the animals were sacrificed and biopsies of the premolar‐molar regions of the mandible sampled. The tissues were prepared for histological analysis using standard procedures. In the sections, 3 zones were identified: zone A=the bone tissue within the distal portion of the previous extraction site (4th premolar), zone B=the pressure side of the 3rd premolar, zone C=the tension side of the 3rd premolar. The area occupied by mineralized bone, Bio‐Oss® particles and bone marrow was determined by a point counting procedure. The width of the periodontal ligament as well as the percentage of the root surface (in zone B) that exhibited resorption was determined.Results: The findings demonstrated that it was possible to move a tooth into an area of an alveolar ridge that 3 months previously had been augmented with a biomaterial. It was also demonstrated that 12 months after grafting, Bio‐Oss® particles remained as inactive filler material in the not utilized part of zone A. The biomaterial was not present in zone C but present in small amounts in zone B.Conclusion: During the orthodontic tooth movement the graft material (Bio‐Oss®) was degraded and eliminated from the part of the alveolar ridge that was utilized for the experiment. In the non‐utilized part of the ridge the biomaterial, however, remained as a seemingly inactive filler material.
A study to assess the plaque inhibitory action of a newly formulated triclosan toothpaste
Authors: Moran J. , Addy M. , Newcombe R. G. , Marlow I. 
Published: August 2010

AbstractBackground/aims: Triclosan containing toothpastes have been noted for their potential to inhibit plaque and gingival inflammation. The aim of this study was to determine whether a toothpaste containing triclosan and an enhanced fluoride system would inhibit de novo plaque formation beyond that of a non‐triclosan, conventional fluoride toothpaste.Methods: This study used a 4‐day plaque regrowth model in which 24 volunteers used toothpaste rinses as the only form of oral hygiene. Following a prophylaxis and a single brushing with the toothpastes, 2× daily rinsing with toothpaste slurries was used over the following 96 h.Results: After 24 h, there was no difference in plaque area between the triclosan paste and its control paste. After 96 h, a reduction in plaque score of 5% was noted for the test toothpaste compared to the control paste which was statistically significant (p=0.028). For plaque area this reduction was increased to 16%, which was also significant (p=0.006).Conclusions: These findings would appear to warrant further investigation into the potential value of the paste in inhibiting both plaque and gingivitis.
Checkerboard assessments of serum antibodies to oral microbiota as surrogate markers of clinical periodontal status
Authors: Papapanou Panos N. , Neiderud Anne‐Marie , Sandros Jens , Dahlén Gunnar 
Published: August 2010

AbstractBackground: This study addresses whether checkerboard assessments of serum IgG antibodies to oral bacteria may serve as surrogate markers of clinical periodontal status in epidemiologic studies.Method: The analysis involved data from 205 subjects, 132 periodontitis patients and 73 periodontally‐intact controls, from whom full‐mouth clinical periodontal data and serum IgG titers against 19 periodontal bacterial species were available.Results: A logistic regression model involving titers against 6 species (Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Eubacterium nodatum, Eikenella corrodens, Capnocytophaga ochracea and Actinomyces naeslundii genospecies 2) classified correctly 74.5% of the subjects examined, with 84% sensitivity, 57.5% specificity, 78% positive predictive value and 66.7% negative predictive value.Conclusions: Checkerboard serology may be useful in providing surrogate markers for clinical periodontal status when such data are not readily available and, thus may serve as a valuable complement in the armamentarium of epidemiologic tools suited for the study of periodontal diseases.
Absence of a specific subgingival microflora in adults with Down’s syndrome
Authors: Reuland‐Bosma W. , Van Der Reijden W. A. , Van Winkelhoff A. J. 
Published: August 2010

AbstractBackground: Periodontal disease in Down’s syndrome (DS) is generally characterized by a high degree of bone loss. Bone loss of 5 mm or more is observed in 70% of these subjects. Among DS subjects, considerable differences in disease progression occur. So far, no studies have been conducted in which specific properties of the subgingival microflora have been related to the condition observed.Aims: To investigate (1) the subgingival microflora in DS subjects and other mentally retarded (control) individuals which were matched to the utmost and (2) to investigate the subgingival microflora of a “low‐risk” and a “ high‐risk” group formed in DS subjects.Material and Methods: 17 DS subjects and 17 control subjects were matched with respect to age, plaque level and bleeding on probing. In addition, the DS group was divided in a “low‐risk” group (0–2 teeth lost due to periodontal disease n=6) and a “high‐risk“group (6–13 teeth lost due to periodontal disease n=11). Prevalence and proportions of the putative periodontal pathogens Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, Peptostreptococcus micros, Fusobacterium nucleatum and Campylobacter rectus in the subgingival plaque were determined using anaerobic culture techniques. No differences in the prevalence of distinct suspected periodontopathic bacteria and bacterial subgingival composition between the DS group and the control group could be established. Also no differences in the prevalence of the seven investigated microbial species between the “low‐risk” and the “high‐risk” group were observed.Conclusions: Because of the lack of differences in microflora between the DS group and the control group, a specific effect of the microbiological composition in the periodontal status of subjects with DS can be excluded in this population. Host factors constitute the more likely explanation of the differences observed in DS.
The effect of chlorhexidine acetate/xylitol chewing gum on the plaque and gingival indices of elderly occupants in residential homes
Authors: Simons D. , Brailsford S. , Kidd E. A. M. , Beighton D. 
Published: August 2010

AbstractAim: A randomised, controlled, double‐blind, clinical trial was conducted to investigate the effect of a chlorhexidine acetate/xylitol gum (ACHX) on the plaque and gingival indices of 111 elderly occupants in residential homes. A gum containing xylitol alone (X) and a no gum (N) group was included. Participants’ opinions about chewing gum were also investigated.Methods: Subjects chewed 2 pellets, for 15 min, 2× daily for 12 months.Results: In the ACHX group, the plaque and gingival indices significantly decreased (p<0.001) over the 12 months. In the X group, only the plaque score significantly decreased (p<0.05) and in the N control group, both indices remained high and did not change significantly. The acceptance of both chewing gums was high but more participants in the ACHX group felt that the gum kept their mouth healthy (p<0.05). The effect of the ACHX gum on plaque and gingival indices was significantly greater than for the X gum.Conclusion: The long‐term use of a chlorhexidine acetate/xylitol chewing gum may therefore support oral hygiene routines for an elderly dependent population.