bluuebunny/crossref_metadata_2025 huggingface dataset:
The anticomplementary activity of lipopolysaccharide preparations and sonicates from a strain of fusobacterium nucleatum
Authors: Hawley Charles E. , Falkler William A.
Published: July 2006

A complement consumption assay was employed to test the consumption of guinea pig complement (GPC) by different sonicate and lipopolysaccharide (LPS) preparations obtained from Fusobacterium polymorphum. The consumption of normal GPC was observed at 37 C and varied depending upon the preparation used. All LPS preparations showed minimal activity at the concentrations employed in the assay. The observed anticomplementary activity was less potent at 4 C than at 37 C. Similar anticomplementary patterns were observed when inulin, a recognized activator of the alternate complement pathway, was tested in the complement consumption assay. The reactions of a sonicate preparation of F. polymorphum with GPC and hyperimmune rabbit antisera were not affected by the lower temperatures. The addition of heat treated (56 C and 30 min) GPC did not enhance the complement consumption displayed by a sonicate of F. polymorphum. It is therefore suggested that this organism is capable of alternate pathway activity in GPC. Further tests revealed that the factors associated with the observed anticomplementary activity were resistant to the effects of heat (100 C for 30 min) and were located in the cell wall fractions of the sonicates. The cell walls also displayed endotoxic activity in a Limulus lysate assay. Because of these findings and the consistency of data produced by the cell walls at 37 C, it is concluded that the use of a cell wall preparation might be preferable to LPS in future investigations of this organism with the complement system.
Periodontal Status of patients iwht abnormalities of the immune system
Authors: Robertson P. B. , Wright T. E. , Mackler B. F. , Lenertz D. M. , Levy B. M.
Published: July 2006

Patients with immune system abnormalities were pair‐matched to immunocompetent clinic patients by age and Plaque Index. Clinical examination included comprehensive health histories with summaries of antibiotic experience, Plaque Index (P 1.I.), Gingival Index (G.I.), Periodontal Disease Index (P.D.I.), caries experience (DMF‐T) and full mouth radiographic surveys. Efficiency of matching was confirmed as tests of significance between sample means for age (11.3, 11.3) and P1.I. (1.33, 1.34) showed no difference between the immunodeficient and clinic patient groups respectively. No clinical or radiographic evidence of attachment loss was noted in either group. A significant and consistent diference was observed in gingival inflammation and caries experience. The G.I. was lower (x̄=1.05) in immunodeficient patients than that recorded in clinic patients (x̄=1.46) in all pairs. Similar results were observed for caries experience, and 8 immunodeficient patients demonstrated DMF‐T scores of zero.
Peroxidases of inflammatory exudate
Authors: Tenovuo J. , Anttonen Tyti , Knuuttila M. L. E.
Published: July 2006

Peroxidase activity of inflammatory exudate collected from rats was studied in relation to the occurrence of leukocytes. The results proved that peroxidase activity correlates with the degadation rate of leukocytes, incresing activities were observed after breakdown of the cells with the aid of 1% Triton X‐100 and decreasing activities after neutropenia produced by cyclophosphamide. Ion exchange and molecular permeation chromatography as well as column and flat‐bed electrofocusing revealed heterogenic forms of exudate perodidases with pI values of 3.9–4.5, 5.7 and 7.2. Certain similarities with the peroxidases of human gingival exudate and rat inflammatory exudate were observed while human neutrophil myeloperoxidase seemed to have different characteristics. Leukocyte peroxidases are known to be antimicrobial against bacteria, fungi, viruses and mycoplasma.
Age‐related alterations of periodontal structures around the cemento‐enamel junction and of the gingival connective tissue composition in germ‐free rats
Authors: Amstad‐jossi M. , Schroeder H. E.
Published: July 2006

Germfree RIC‐Sprague‐Dawley rats, ranging in age between 30 and 80 days, were used to establish age‐related changes in the periodontal tissues around upper and lower molars. At consecutive steps with a 10‐day interval each, uper and lower jaws of these animals were excised and processed for (1) direct observation and histometric measurements connective tissue composition. The data obtained suggested that during the observational period (1) the distance between the cemento‐enamel junction and the alveolar bone crest increased at the lingual side of lower first and the palatal and lingual side of upper and lower second molars but, on any other site, remained constant with time, (2) the junctional epithelium sporadically retracted in coronal direction at all sides of upper and lower molars but, interdentally between first and second molars, this retraction was accompanied by the formation of afibrillar cementum spurs overlapping the cervical enamel, (3) the size and numerical density of gingival fibroblasts changed, while the overall volume density of collagen, except at the oral site, remained constant with time. These age‐dependent alterations are of considerable interest when studying inflammatory periodontal destruction as well as in relation to tooth eruption and connective tissue turnover.
Histopathology of periodontal disease in gnotobiotic rats monoinfected with Eikenella corrodens
Authors: Listgrarten M. A. , Johnson D. , Nowotny A. , Tanner A. C. R. , Socransky S. S.
Published: July 2006

The histopathology of periodontal disease was studies in gnotobiotic rats monoinfected with Eikenella corrodens, a Gram‐negative rod isolated from a human periodontitis lesion. Animals were sacrificed in pairs from 2–14 weeks after infection and the molar segments scored for severity of periodontal disease by visual inspection. the lesions first appeared in the maxillary molars and were after infection in the maxilla than in the mandible. Specimens taken 2 weeks after infection showed hair impaction in the coronal part of the junctional epithelium and some leukocyte emigration, but no evidence of a cellular infiltrate or vascular anomalies in the connective tissue. Between 3–5 weeks, a crater‐like depression developed interdentally within the connective tissue, the surface of which was Covered by a continous epitheliel lining disrupted by impacted debris. Little mogrationof the epithelial attachment was noted apical to the cemento‐enamel junction. Between 6–8 weeks. The interdental epithelial lining became ulcerated. Impacted hair and other debris were commonly noted within the connective tissue which, however, remained free of plasma cells and only contained isolated lymphocytes. Bone destruction was characterized by marked osteoclastic activity. The tooth Surfaces remained remarkably free of adherent bacteria. In fact, bacteria were only observed in one 13‐week specimen, in association with impacted debris. Contrary to the progress of periodontal breakdown in man and some other species, the most apical extent of the disease process in these animals was located along the central portion of the interdental tissues, rather than along the root surfaces. No correlation or possibly an inverse correlation seemed to exist between the severity of priodontal disease in these animals and their cell‐madiated immune response to the infecting organism.
Construction of an immobilization sling for dog research
Authors: Kopczyk Anthony J. , Kopczyk Raymond A. , Saxe Stanley R.
Published: July 2006

The need for a research to immobilize experimental dogs led to the development of an immobilization sling. Directions for its use and construction data are provided because of the numerous requests received for information on the University of Kentucky College of Dentistry's method of handling dogs for dental research.
The width of attached gingiva on supraerupted teeth
Authors: Ainamo Anja , Ainamo Jukka
Published: July 2006

On basis of earlier results it seems justified to assume that the antomical width of the attached gingiva, i.e. the distance from the mucogingival junction to the cemento‐enamel junction in human type of teeth is in direct proportion to the amount of past tooth eruption. For experimental verification of this hypothesis a study was designed to assess the anatomical width of attached gingiva on supraerupted teeth in man. The material of the sutdy comprised 28 first and second maxillary mucogingival junction was marked with short pieces of metal wire, orthopantomograms were taken, and the distances from the mucongingival junction to the floor of the nasal cavity and to the cemento‐enamel junction used as controls. A comparision wa also made between the supraerupted teeth and previously measured normally occluding teeth. The results indicated that even during pronounced supraeruption the teeth tend to erupt with their investing tissues while the location of the mucogingival junction remains constant. This finding is of special interest as it should make it possible to treat the problem of a too narrow zone of attached gingiva by grinding the tooth out of occlusion and allowing it and its gingival margin to erupt.
Cell mediated immune responses to plaque antigens during experimental gingivitis in man
Authors: Smith Frederic N. , Lang Niklaus P. , Löe Harald A.
Published: July 2006

The purpose of the present investigation was to evaluate the ability of antigens of human dental plaque microorganisms to stimulate peripheral blood lymphocytes (PBL) from humans during the development and recovery from experimental gingivitis.

Eleven healthy dental students (22–36 years) participated in the study. At the start of the experiment, they exhibited clean teeth and clinically healthy gingivae. They then abstained from all oral hygiene measures for four weeks according to the model proposed by Löe et al. (1965). At the start, after 1, 2, 3 and 4 weeks of abolished oral hygience and 2 weeks following reinstitution of oral hygiene, the oral conditions were assessed, using the critieria of the Plaque Index system (Löe & Silness 1964) and the Gingival Index system (Löe & Silness (1963).

At each examination triplicate microcultures, each containing 2 × 105 viable PBL in .2 ml TC 199 with glutamine and antibiotics containing 10% fetal calf serum, were stimulated with four concentrations of sonicates from V. alcalescens, F. nucleatum, B. melaninogenicus, A. viscosus, A. naeslundii, S. sanguis and pooled dental plaque all obtained from the previsouly performed experimental gingivitis. The cultures were incubated for 78 hours at 37°C in 5% CO2. 3H‐thymidine was added for the final 8 hours.

Only A. viscosus was able to stimulate PBL to undergo blastogenesis during the development of experimental gingivitis. A. viscosus stimulated the PBL of 3 subjects after one week but all subjects after 2 weeks of abolished oral hygiene. The stimulation indices (SI) remained >2.5 for the rest of the experimental period. Following 2 weeks of reinstituted oral hygiene, the SI reached preexperimental levels.

These results suggest that A. visocus is capable of inducing a specific cellular immune response during the development of experimental gingivitis and may be important as a causative plaque constituent. Further research is indicated to study this association.
The effect of immunosuppressive agents on periodontal disease in man
Authors: Tollefsen T. , Saltvedt E. , Koppang Hanna Strømme
Published: July 2006

Established chronic gingival lessions were studies in four categories of patients. One groups of healthy subjects was kept plaque‐free (CO), while in the second group (CP) moderate accumulations of dental plaque were permitted. The third group (UH) comprised patients with uremia and in hemodialysis. A fourth group (IS) had received renal allografts and was kept on an immunosuppressive regimen. Differential blood counts and serum immunoglobin quantitation from the UH and IS groups gave mean values within normal ranges. Gingival biopsies were obtained from each subject. The connective tissue inflammation (CTI) scores were compared between the groups. Despite abundant local plaque accumulations, the UH group displayed essentially the same CTI scroes as plaque‐free controls (CO), while the IS group showed a significantly lower (p < 0.05) CTI score than the two in question. The CTI scores of the CP group (controls with plaque) were significantly higher (P < 0.01) than those of the UH, IS and CO groups. It is concluded that immunologic homeostasis is important in the periodontal tissue of man.
Bacterial bone resorption in advanced cases of human periodontitis
Authors: Frank R. M. , Voegel J. C.
Published: July 2006

In advanced cases of human periodontitis with pocket depths over 4 mm, severe tooth mobility and bone loss involving approximately two‐thirds of the alvelor height as assessed radiographyically, numerous Gram negative and Gram postitive filamentous, rodshaped, and coccoid bacteria were seen inflitrating the periodontal ligament, coming into close contact with the alveolar bone surface and even invading superfical osteocyte lacunae. Typical bone resporption occured along the bacterial front. This was characterized by a scattered dissolution of individual apatite crystals denuding corssstriated collagen fibrils which were finally destroyed. In the vicinity of such areas, two types of calculus formation were observed in the ligament. Calcification occurred at the surface and between the microorganisms with entrapped bacterial remnants. The second type of calcification developed on cellular remnants. The presence of microorganisms alongs resorbing alveolar bone surfaces in advanced cases of periodonitis cannot be considered as an artifact.
Measurement of human gingival sulcus temperature
Authors: Ng G. C. , Compton F. H. , Walker T. W.
Published: July 2006

With the ambient temperature well regulated (22.8 + 0.2°C, mean ± 95 % confidence limits) the gingival sulcus temperatures of 21 human subjects were measured, and gingival plaque indices recorded. All subjects had clinically healthy gingiva. The sulcus temperatures of the mandibular teeth were found to be higher than those of the maxillary teeth by 0.7 ± 0.2°C. In both arches, the sulcus temperatures of the molars exceeded those of the incisors by 1.5 ± 0.3°C, this difference being statistically significant. The mean gingival sulcus temperature averaged over the entire dentition was found to be 33.9 ± 0.4°C. Attempts to show a correlation between gingival inflammation and sulcus temperature, although unsuccessful, suggested that such a correlation might be demonstrated through the use of more sophisticated instrumentation. The profile of normal gingival sulcus temperatures established herein shows a marked agreement with published data concerning the distribution of the blood supply to the periodontal ligaments of individual human teeth. It could serve as a reference for studies of heat transfer in dental and periodontal tissues as well as providiong a clinical norm for use in the assessment of periodontal inflammation.
The natural history of periodontal bone loss in germfree and gnotobiotic rats infected with Periodontopathic microorganisms
Authors: Crawford John M. , Taubman Martin A. , Smith Daniel J.
Published: July 2006

A new technique for evaluating the vertical component of bone loss in rats is described in which silicone base impression material is utilized. The extent and pattern of bone loss in germfree rats is compared to the bone loss in gnotobiotic animals infected with either Streptococcus mautans strain 6715 or with Actinomyces naeslundii strain I or with Actinomyces viscosus strain T 14. In general, after approximately 60 days of infection the gnotobiotic animals demonstrated patterns of bone loss similar to germfree animals although the extent of loss was more marked. The major increases in bone loss (both horizontal and vertical) were observed in the period between 60 and 90 days of infection. The major destruction offurs on the lingual aspects of maxillary molars. Vertical bone loss was greater in A. naeslundii infected animals than in S. mutans infected animals.
Histological changes in experimental periodontal disease in rats monoinfacted with gram‐negative organisms
Authors: Irving J. T. , Socransky S. S. , Tanner A. C. R.
Published: July 2006

Groups of weanling gnotobiotic rats of the Sprague‐Dawley strain were monoinfected with isolates of Cappocytophaga, strains 4, 6 and 27, and with Fusobacterium nucleatum, strain 325, Bacteroides strain 289c and Eikenella corrodens, strain 1073. All caused periodontal disease between the first and second maxillary molars, with migration of the epithelial attachment, destruction of the alveolar bone by osteoclasts and impaction of debris. No plaque was formed. Capnocytophaga, strain 4, caused almost complete destruction of the periodontium by 42 days. The other organisms were less pathogenic, but all caused considerable destruction of the periodontium by 84 days.
Surface ultrastructure of human gingiva
Authors: Cleaton‐Jones P. , Buskin S. A. , Volchansky A.
Published: July 2006

Specimens of clinically healthy keratinized human gingiva from the buccal, palatal and lingual surfaces of the maxilla and mandible were examined under the light microscope and scanning electron microscope. Light microscopy confirmed that the gingiva was cilinically healthy. Scanning electron microscopy showed the presence of irregular depressions, corresponding to the macroscopic stipples, on the buccal gingiva but not on palatal or lingual gingiva. The oral surface of the most superficial cells was covered with micropits.
A survey of toothbrushing behaviour in children and young adults
Authors: Rugg‐Gunn A. J. , Macgregor I. D. M.
Published: July 2006

Eighty‐seven sunjects from 3 age groups (5, 11 and 18–22 yr) were asked to brush their teeth and were unaware that they were recorded on video tape. from repeated viewing of the films the following data were obtained: the areas of the mouth which were brushed, the brushing stroke used in each area, the total brushing time and the proportion of time spent on each area. In each of the three age groups, the proportion of the areas that were brushed was 25, 50 and 67 per cent, respectively. MOre time was spent brushing the lower than the upper teeth, and the contra‐lateral side (the left side in right‐handed persons) was brushed more than the ipse‐lateral sinde in children but equally in adults. Less than 10 per cent of the time was spent brushing lingual areas. The most populor brushing strokes were the horizontal in children and the vertical in adults; the roll and circular strokes were seldom used. Eighty‐four per cent of subjects used more than one type of brushing stroke.
Clinical and structural alterations characterizing healing gingiva
Authors: Lindhe Jan , Parodi Ricardo , Liljenberg Birgitta , Fornell Jan
Published: July 2006

The aim of the present study was to compare the structural composition of the gingiva of dogs which had not previously suffered from inflammation with that of gingiva which for 6 months had been inflamed, but subsequently healed. The experiments were carried out in eight dogs. After weaning, the dogs were daily subjected to tooth cleaning. When the animals were 10 months old a clinical examination was carried out after which the dogs were randomly distributed into two groups, A and B. Immediately after the clinical assessments, gingival biopsies were obtained from the premolars and molars of the dogsof Group A. The dogs of Group B were allowed to accumulate plaque during a 6‐month period after which the examinations were repeated and biopsies were sampled from predetermined areas of the dentition. Following biopsy the remaining teeth of the dogs of Group B were scaled. During the subsequent 6 weeks, the animals were daily subjected to tooth cleaning. The examinations were repeated and biopsies sampled on days 4, 7, 14, 21, 28 and 42. The biopsy material was subjected to morphometric analysis. The resuls showed that it is possible to shift a chronically inflamed gingiva into one which, from a clinical and structural point of view, is almost identical to a gingiva which has never been exposed to gross plaque accumulation. This shift was achieved by elimination of calculus and plaque and by the institution of a careful, daily practiced plaque control program. During healing, the inflammatory cell infiltrate in the connective tissue below the junctional epithelium gradually disappeared and became replaced by collagen. In comparison to inflamed gingiva during healing, the leukocyte content of the junctional epithelium was reduced, whle ee peg formations remained. In the connective tissue papillae beneath these rete pegs, vessels could be recognized. This gave the connective tissue of the healed gingiva a higher vascular content thatn that of a gingiva which had not previously suffered from inflammation.
Leptotrichia buccalis hemagglutination in cell binding and salivary inhibition studies
Authors: Falkler William A. , Hawley Charles E. , Mongiello James R.
Published: July 2006

The characteristic hemagglutination (HA) of Leptotrichia buccalis was used for measuring its attachment to various human cells and for determining if saliva contained hemagglutination inhibition (HI) factors. The microbial strain utilized displayed the chaacteristic EM morphology of L. buccalis. Sonicated preparations of the organism were tested for HA activity before and after adsorption with human cells. Buccal epithelial cells, red blood cells (RBC), HeLa and embryonic kidney cells all bound the HA fragments of the organisms. The bacterial fragments on the cells could be observed by fluorescent antibody testing. The fragments were released from the cells used for adsorption with chelators and upon addition of CaCl2 the HA activity returned. Whole saliva displayed hemagglutination inhibition activity in a manner suggesting a binding site interaction. The similarity of the HA activity of F. nucleatum is discussed as ae the relationships of cell binding to colonization of the organisms and immunopathology to host cells.
IgG subclasses in human periodontal disease
Authors: Mackler Bruce F. , Faner Richard M. , Schur Peter , Wright Thomas E. , Levy Barnet M.
Published: July 2006

Lymphocyte membrane‐associated IgG subclass antibodies in human periodontal disease were studied to ascertain the elative presence of cytophilic IgG antibodies and the membrane Fc receptors which bind them. The experimental approach correlated the efect of incubating gingiva in tissue culture medium to remove cytophilic antibodies with the changes in the number of Fc receptors detectable after washing. The evidence indicated that the majority of lymphocytes in mild gingivitis lesions lacked cytophilic IgG antibodies as well as Fc receptors. IN severe gingivitis, the number of IgG subclass bearing lymphocytes increased to about half of the total lymphoid population, while the perentage of Fc receptor bearing cells remained qite low (12.3%± 3.2, S.E.). The majority of IgG subclass bearing lymphocytes had membrane IgG which serve as receptors for antigen; such cells are classically defined as bone marrow (B) derived lymphocytes and serve as the progenitor for plasma cells. Gingival specimens for patients with periodontitis were found to contain the highest percentage of Fc receptor bearing lymphocytes (38.3%± 12.6 S.E.) and cytophilic IgG antibodies. The findings indicae tha the clinical stages of human perodontal disease are characterized by different populations of infiltrating lymphocytes.
The effect of levamisole on experimental gingivitis in juvenile periodontitis
Authors: Budtz‐Jörgensen E. , Ellegaard B. , Ellegaard J. , Jörgensen F. , Kelstrup J.
Published: July 2006

In four patients with juvenile periodontitis (group A), five adults with advanced periodontitis (group B), and in four controls (group C) the concentration of serum immunoglobulins, serum complement (C3C4, and C5) T and B lymphocyte ratio, leukocyte migration inhibition and lymphocyte transformation responses to dental plaque bacteria (A. viscosus, B. melaninogenicus, F. nucleatum, and V. parvula) and PPD or PHA, and lymphocyte ATP‐ase activity were assessed before and during development of experimental gingivitis.

All the patients in group A and B Had completed extensive periodontal treatment, and at the time of the experiment the periodontal conditions were excellent. Plaque accumulation and gingival inflammation were assessed and blood samples were drawn: at day 0; after plaque accumulation for 14 d (no oral hygiene) (period I); after 14 d with optimal oral hygiene (period II); after plaque accumulation for 14 d (no oral hygiene) and concomitant immunostimulatory treatment with levamisole (period III); after 14 d with optimal oral hygiene. After period I, gingival inflammation and increased gingival fluid flow developed in all groups; however, in group C some of the clinical and immunological responses were slightly enhanced as compared wiht group A and group B. On the other hand, after period III (plaque accumulation + levamisole) more pronounced clinical and immunological changes were recorded in group A and B than in group C, including a significant rise in gingival fluid flow, LIF production, and lymphocyte ATP‐ase activity. The present study has supported the asumption that a state of immunodeficiency can be an underlying, predisposing factor for juvenile periodontitis. The results, however, give only vague information on the nature of this deficiency
The in vitro inhibition of microbial growth and plaque formation by surfactant drugs
Authors: Baker P. J. , Coburn R. A. , Genco R. J. , Evans R. T.
Published: July 2006

Several cationic, mixed and amphoteric surfactants were tested for their antimicrobial activity and ability to inhibit the formation of in vitro plaque by oral microorganisms. All had antimicrobial activity against Actinomyces viscosus. Actinomyces naeslundii and Streptococcus mutans. Cationic surfactants were comparable to chlorhexidine in antimicrobial activity but were less effective in inhibiting plaque formation. Amphoteric surfactants were less effective than other detergents in antibacterial activity and had very limited capacity for the inhibition of plaque formation. Comparison of drug structure provides evidence that surfactant substantivity to saliva‐coated enamel is a cation active process. Saliva was found to have an antagonistic effect on the activity of cetylpyridinium chloride but not on Triburon.
A scanning electron microscopic study of the destruction of human alveolar crest in periodontal disease
Authors: Ooya K. , Yamamoto H.
Published: July 2006

The crestal surfaces of human alveolar bone obtained at autopsy were studied by scanning electron microscopy. Healthy alveolar crests were covered by supracrestal fivers, making it difficulst to prepare and visualize collagen‐free crestal bone. The incipient stage of the destruction fo the alveolar crestal bone was associated with a loosening of the supracrestal fivers. Bone surfaces free fo supracrestal fibers were easily prepared from the active inflamatory lesions. These denuded bone surface were characterized by numerous Howship's lacunae. In the resting stage, the alveolar crest had a honeycomb appearance with a covering plexus of collagen fibers and mineralized‐like collagen matrix. It was concluded that the destructoin of supracrestal fibers was important in the process of the destruction of the alveolar crestal bone, which proceeded by osteoclastic resorption.
Experimental bifurcation defects in dogs
Authors: Johansson Owe , Nilvéus Rolf , Egelberg Jan
Published: July 2006

This study utilizes andf experimental model in beagle dogs in which chronic bifurcation defects are induced by passing a round bur through the denuded bifurcations of the premolars in the lower jaw (Ellegaard et al. 1973). Immediate spontaneous healing was avoided by inserting a steel wire through the created bifurcation defects. The wire was ligated over the crown and left in place for six weeks. A split mouth technique was used in order to compare the furcation lesions at two and nine months after creation. Histological observations and meansurements indicate that chronic lesions with characteristics similar to those in man were obtained.
The natural history of periodontal disease in man
Authors: Löe Harald , ÅNerud ÅGe , Boysen Hans , Smith Martyn
Published: July 2006

This is the first in a series of reports on a longitudinal investigation of the initiation and progress of periodontal disease in man. One group was established in Norway in 1969 and consisted of 565 male students and teachers between 17 and 30+years. A second group of comparable age was established in Sri Lanka in 1970 and consisted of 480 tea laborers. Both groups were scored for various disease parameters at start and at intervals during the subsequent seven years. This paper describes the design of the investigation and periodontal state of the two groups at baseline.

The results show that th Norwegian group had good to excellent oral hygiene and mild gingivitis. Supra‐and subgingival calculus were inconspicous and untreated slowly with age. The mean loss of attachment in the 30+year old was less than one millimeter.

Tht Sri Lankan tea laborers showed poor oral hygiene, abundance of calculus and generalized moderate to severe gingivitis. Caries and dental restorations were non‐existent. Slight loss of attachment was seen in the 15year old and increased through the twenties. The 30+years old Sri Lankan tea laborer showed a mean loss of more than 3 mm and a subsantial number of teeth exhibited attachment loss in excess of 10 mm.

The baseline analysis indicated that due to the choice of study groups and design, the longitudenal data will lend themselves to describing the initiation, pattern of development and the rate of progress of periodontal disease during major portions of the abult life of these people.
Phagocytosis of Bacteroides melaninogenicus and Bacteroides gingivalis in vitro by human neutrophils
Authors: Sundqvist Göran , Bloom Gunnar D. , Enberg Kjell , Johansson Eva
Published: July 2006

Phagocytosis of Bacteroides melaninogenicus (five strains) and Bacteroides gingivalis (two strains) was studied by electron microscopy. The chemiluminescent response of bacteria‐challenged polymorphonuclear leukocytes was also measured. There was a correlation between the ability of the bacteria to induce chemiluminescence in polymorphonuclear leukocytes and the cellular uptake of the bacteria. Four of the five B. melaninogenicus strains were phagocytized within 10 min, while for one strain the phagocytic response was delayed. Cells of this strain were surrounded by a loosely bound layer of intermediate electron density. One of the B. gingivalis strains was phagocytized to the same extent as the B. melaninogenicus strains. The other B. gingivalis strain resisted phagocytosis. Cells of this strain were surrounded by an electron dense layer. When comparing previous results on the pathogenicity of these strains in experimental polymicrobial infections in guinea pigs with the present results on phagocytosis, it is apparent that all the pathogenic B. metaninogenicus strains were phagocytized in vitro, while the non‐pathogenic strain of B. gingivalis was phagocytized and the pathogenic strain was not.
Periodontal disease associated with Shigella flexneri in rhesus monkeys
Authors: Armitage G. C. , Newbrun E. , Hoover C. I. , Anderson J. H.
Published: July 2006

The clinical, microbiologic, and histopathologic features of Shigella flexneri‐associated periodontal disease of rhesus monkeys were examined. Eighteen subgingival plaque samples and 17 gingival biopsy specimens were taken from 8 rhesus monkeys harboring S. flexneri orally. All plaque samples and three of the biopsy specimens were processed aerobically and anaerobically on selective and nonselective media. The remaining biopsy specimens were prepared for light or electron microscopic observation. An additional 11 subgingival plaque samples from 6 monkeys not suspected of orally harboring S. flexneri were also processed microbiologically.

In the monkeys harboring Shigella orally, S. flexneri serotype 4 was isolated from 16 of the 18 subgingival plaque samples. It constituted a minor plaque component in all 16 positive sites, usually less than 0.1 % of the recoverable flora. S. flexneri was not detected in any of the subgingival plaques from control monkeys. Gingival sites harboring S. flexneri were characterized by extremely intense clinical inflammation. Histopathologic observations included ulceration of the pocket wall and heavy lymphocytic and plasma cell infiltration of the connective tissue. At the ultrastructural level, unidentified bacteria were occasionally observed between, and possibly within, intact epithelial cells adjacent to areas of ulceration.

The results suggest that S. flexneri, though a numerically minor component of the plaque flora, may be important in the pathogenesis of the periodontal disease observed in this study.
In vitro breakdown of gingival tissue by elastase from human polymorphonuclear leukocytes An electron microscopic study
Authors: Cergneux M. , Andersen E. , Cimasoni G.
Published: July 2006

Several biopsies of human marginal gingiva were collected from clinically healthy and from slightly inflamed sites. The biopsies from one given site were divided and treated as follows: one portion was immediately fixed and used as a reference; the others were incubated for two hours either in culture medium alone, or in the same medium with different concentrations of elastase purified from human polymorphonuclear leukocytes. The biopsies were then fixed and examined by electron microscopy. It was found that elastase caused an enlargement of the intercellular spaces of the oral gingival epithelium, interruptions of the basement lamina, and loss of collagen in the underlying connective tissue.

Biopsies collected from severely inflamed sites were also studied in the electron microscope. Some of the ultrastructural alterations observed in these inflamed tissues were similar to those experimentally induced by elastase.
Effect of training and probing force on the reproducibility of pocket depth measurements
Authors: Abbas F. , Hart A. A. M. , Oosting J. , van der Velden U.
Published: July 2006

The purpose of the present investigation was to study the effect of standardization of probing spot and direction of probe insertion into the pocket in conjunction with a probing force of 0.75 N on the reproducibility of pocket depth measurements. Nine patients were selected on the basis of about 50 % loss of alveolar bone support. After initial treatment 137 interproximal pockets were measured twice by three different examiners, successively by means of a pressure probe with a constant probing force of 0.75 N and a Merritt‐B probe. During the next two weeks the examiners were trained by means of a video program to use the probe on a standardized spot and in a standardized direction of insertion into the pocket. After this training, all measurements were repeated in the same order of investigation. During the first as well as the second examination, the first examiner also scored bleeding on probing using the pressure probe. Analyses of variance were carried out in order to test the reproducibility of pocket depth measurements both before and after training. Possible influences of the depth of the pocket and the bleeding tendency of a pocket were included in the analyses. The results indicated that only a training program together with a standardized probing force leads to reproducible interproxima! pocket depth measurements. However, further analyses revealed that only non‐bleeding pockets gave reproducible measurements whereas bleeding pockets did not. If, in addition, pocket depth was included in the analyses, it was found that this factor has no influence on the reproducibility. It was concluded that bleeding of a pocket seems to be more important for the reproducibility of pocket depth measurements than the factor pocket depth.
The effect of culture filtrates of oral strains of black‐pigmented Bacteroides on the matrix production of chick embryo cartilage cells in vitro
Authors: Touw J. J. A. , van Kampen G. P. J. , van Teenbergen T. J. M. , Veldhulizen J. P. , de Graaff J.
Published: July 2006

Culture filtrates of strains of Bacteroides gingivalis and Bacteroides asaccharolyticus contain a heat stable factor which inhibits the production of extracellular matrix by chick embryo chondrocytes and which causes vacuolization of these chondrocytes. This morphological effect appeared to be reversible. Strains of the saccharolytic species Bacteroides melaninogenicus did not have these effects. The significance of this cytotoxic effect for the etiology of periodontal diseases is discussed.
Blood flow in gingiva and alveolar bone in beagles with periodontal disease
Authors: Kaplan M. L. , Jeffcoat M. K. , Goldhaber P.
Published: July 2006

Radiolabeled microspheres were used to measure gingival and alveolar bone blood flow in beagles with periodontal disease. The severity of periodontal disease was determined using radiographs, and the percent alveolar bone loss around specific tooth areas was calculated. Gingiva and alveolar bone blood flows were lowest in dogs with minimal periodontal disease (< 10% bone loss) while dogs with moderate to severe disease (> 20% bone loss) had periodontal blood flows 250–400% greater (p < .05). In all animals maxillary alveolar bone had higher blood flow than corresponding mandibular bone (p < .05) whereas gingival blood flow between jaws was similar.
Tensile behaviour of the periodontal ligament
Authors: Ralph W. J.
Published: July 2006

Transverse sections of human periodontal ligament were subjected to tensile loads. Extension‐time, load‐time, and load‐extension curves were obtained. The average value for the ultimate tensile strength of the ligament was found to be 2.4 N/mm2. Loading of the ligament for either extrusion or intrusion did not appear to change its behaviour.
Identification of tyrosine‐phosphorylation sites in the nuclear membrane protein emerin
Authors: Schlosser Andreas , Amanchy Ramars , Otto Henning
Published: June 2006

Although several proteins undergo tyrosine phosphorylation at the nuclear envelope, we achieved, for the first time, the identification of tyrosine‐phosphorylation sites of a nuclear‐membrane protein, emerin, by applying two mass spectrometry‐based techniques. With a multiprotease approach combined with highly specific phosphopeptide enrichment and nano liquid chromatography tandem mass spectrometry analysis, we identified three tyrosine‐phosphorylation sites, Y‐75, Y‐95, and Y‐106, in mouse emerin. Stable isotope labeling with amino acids in cell culture revealed phosphotyrosines at Y‐59, Y‐74, Y‐86, Y‐161, and Y‐167 of human emerin. The phosphorylation sites Y‐74/Y‐75 (human/mouse emerin), Y‐85/Y‐86, Y‐94/Y‐95, and Y‐105/Y‐106 are located in regions previously shown to be critical for interactions of emerin with lamin A, actin or the transcriptional regulators GCL and Btf, while the residues Y‐161 and Y‐167 are in a region linked to binding lamin‐A or actin. Tyrosine Y‐94/Y‐95 is located adjacent to a five‐residue motif in human emerin, whose deletion has been associated with X‐linked Emery–Dreifuss muscle dystrophy.
Biochemical characterization of annexin B1 from Cysticercus cellulosae
Authors: Winter Anja , Yusof Adlina M. , Gao Erning , Yan Hong‐Li , Hofmann Andreas
Published: June 2006

Annexin B1 from Cysticercus cellulosae has recently been identified using immunological screening in an attempt to find novel antigens for vaccine development against cysticercosis. The protein possesses anticoagulant activity and carries significant therapeutic potential due to its thrombus‐targeting and thrombolytic properties. We investigated the biochemical properties of annexin B1 using liposome and heparin Sepharose copelleting assays, as well as CD spectroscopy. The calcium‐dependent binding to acidic phospholipid membranes is reminiscent of other mammalian annexins with a clear preference for high phosphatidylserine content. A unique property of annexin B1 is its ability to bind to liposomes with high phosphatidylserine content in the absence of calcium, which might be due to the presence of several basic residues on the convex protein surface that harbours the membrane‐binding loops. Annexin B1 demonstrates lectin properties and binds to heparin Sepharose in a cooperative, calcium‐dependent manner. Although this binding is reversible to a large extent, a small fraction of the protein remains bound to the glycosaminoglycan even in the presence of high concentrations of EDTA. Analogous to annexin A5, we propose a model of heparin wrapped around the protein thereby engaging in calcium‐dependent and calcium‐independent interactions. Although the calcium‐independent heparin‐binding sites identified in annexin A5 are not conserved, we hypothesize three possible sites in annexin B1. Results from CD spectroscopy and thermal denaturation indicate that, in solution, the protein binds calcium with a low affinity that leads to a slight increase in folding stability.
Enhancing thermostability of maltogenic amylase from Bacillus thermoalkalophilus ET2 by DNA shuffling
Authors: Tang Shuang‐Yan , Le Quang‐Tri , Shim Jae‐Hoon , Yang Sung‐Jae , Auh Joong‐Huck , Park Cheonseok , Park Kwan‐Hwa
Published: June 2006

DNA shuffling was used to improve the thermostability of maltogenic amylase from Bacillus thermoalkalophilus ET2. Two highly thermostable mutants, III‐1 and III‐2, were generated after three rounds of shuffling and recombination of mutations. Their optimal reaction temperatures were all 80 °C, which was 10 °C higher than that of the wild‐type. The mutant enzyme III‐1 carried seven mutations: N147D, F195L, N263S, D311G, A344V, F397S, and N508D. The half‐life of III‐1 was about 20 times greater than that of the wild‐type at 78 °C. The mutant enzyme III‐2 carried M375T in addition to the mutations in III‐1, which was responsible for the decrease in specific activity. The half‐life of III‐2 was 568 min while that of the wild‐type was <1 min at 80 °C. The melting temperatures of III‐1 and III‐2, as determined by differential scanning calorimetry, increased by 6.1 °C and 11.4 °C, respectively. Hydrogen bonding, hydrophobic interaction, electrostatic interaction, proper packing, and deamidation were predicted as the mechanisms for the enhancement of thermostability in the enzymes with the mutations.
Identification and characterization of oxidized human serum albumin
Authors: Kawakami Asami , Kubota Kazuyuki , Yamada Naoyuki , Tagami Uno , Takehana Kenji , Sonaka Ichiro , Suzuki Eiichiro , Hirayama Kazuo
Published: June 2006

Human serum albumin (HSA) exists in both reduced and oxidized forms, and the percentage of oxidized albumin increases in several diseases. However, little is known regarding the pathophysiological significance of oxidation due to poor characterization of the precise structural and functional properties of oxidized HSA. Here, we characterize both the structural and functional differences between reduced and oxidized HSA. Using LC‐ESI‐TOFMS and FTMS analysis, we determined that the major structural change in oxidized HSA in healthy human plasma is a disulfide‐bonded cysteine at the thiol of Cys34 of reduced HSA. Based on this structural information, we prepared standard samples of purified HSA, e.g. nonoxidized (intact purified HSA which mainly exists in reduced form), mildly oxidized and highly oxidized HSA. Using these standards, we demonstrated several differences in functional properties of HSA including protease susceptibility, ligand‐binding affinity and antioxidant activity. From these observations, we conclude that an increased level of oxidized HSA may impair HSA function in a number of pathological conditions.
Triose phosphate isomerase, a novel enzyme‐crystallin, and τ‐crystallin in crocodile cornea
Authors: Kathiresan Thandavarayan , Krishnan Kannan , Krishnakumar Vaithilingam , Agrawal Raman , Anand Amit , Muralidhar Dasari , Mishra Anurag K. , Dhople Vishnu M. , Aggrawal Ramesh K. , Sharma Yogendra
Published: June 2006

Several enzymes are known to accumulate in the cornea in unusually high concentrations. Based on the analogy with lens crystallins, these enzymes are called corneal crystallins, which are diverse and species‐specific. Examining crystallins in lens and cornea in multiple species provides great insight into their evolution. We report data on major proteins present in the crocodile cornea, an evolutionarily distant taxon. We demonstrate that τ‐crystallin/α‐enolase and triose phosphate isomerase (TIM) are among the major proteins expressed in the crocodile cornea as resolved by 2D gel electrophoresis and identified by MALDI‐TOF. These proteins might be classified as putative corneal crystallins. τ‐Crystallin, known to be present in turtle and crocodile lens, has earlier been identified in chicken and bovine cornea, whereas TIM has not been identified in the cornea of any species. Immunostaining showed that τ‐crystallin and TIM are concentrated largely in the corneal epithelium. Using western blot, immunofluorescence and enzymatic activity, we demonstrate that high accumulation of τ‐crystallin and TIM starts in the late embryonic development (after the 24th stage of embryonic development) with maximum expression in a two‐week posthatched animal. The crocodile corneal extract exhibits significant α‐enolase and TIM activities, which increases in the corneal extract with development. Our results establishing the presence of τ‐crystallin in crocodile, in conjunction with similar reports for other species, suggest that it is a widely prevalent corneal crystallin. Identification of TIM in the crocodile cornea reported here adds to the growing list of corneal crystallins.
Biology of suckers: late‐formed shoots in sugarcane
Authors: BONNETT G D , SALTER B , ALBERTSON P L
Published: July 2006

Suckers in sugarcane are tillers that form late in the growing season after the population of main stalks has been established. Their biology has rarely been studied, though unsubstantiated comments relating to their morphology, development and number are abundant. In this paper, the literature is reviewed and new experiments presented. Comparison of suckers, emerging plant and ratoon cane showed that suckers have a different leaf and stem morphology. Suckers have a greater diameter at their stem base and shorter and wider leaves than primary stalks of a similar age. In 1 ‐year‐old crops, suckers have been demonstrated to decrease the net sucrose concentration of harvested material by diluting sucrose in the main stalks. By comparing main stalks without suckers to those that have initiated suckers, evidence is presented that suckers may also be decreasing the sucrose content of the stalks from which they are growing. Genotypic and environmental factors influence sucker number. Several experiments were designed to identify environmental stimuli for suckering. Increased nitrogen, through application late in the growing season, was found to increase the numbers of suckers present. Manipulation of the light environment of main stalks showed that a change in light quality (but not necessarily quantity) stimulated suckering. Further work is underway to define how these environmental stimuli lead to sucker initiation and growth. Major scientific questions that should be addressed are: the identification of other potential environmental stimuli, how the signals are perceived and translated into sucker initiation, and why suckers have different morphology. The practical challenge is to combine the new information about sucker biology and develop from it strategies to alter agronomy and select new cultivars that results in decreased suckering.