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Biomedical subjects

A Tanner

Publications and source records attributed to A Tanner.

At least 37 records · Page 2Linked to original sources
PubMed1998

Subgingival microbiota in healthy, well-maintained elder and periodontitis subjects.

This investigation compared the site prevalence of 40 subgingival species in 30 periodontally healthy (mean age 36+/-9 years), 35 elders with a well-maintained periodontium (mean age 77+/-5) and 138 adult periodontitis subjects (mean age 46+/-11). Subgingival plaque samples were taken from the mesial aspect of each tooth (up to 28 samples) in the 203 subjects at baseline. The presence and levels of 40 subgingival taxa were determined in 5003 plaque samples using whole genomic DNA probes and checkerboard DNA-DNA hybridization. Clinical assessments including dichotomous measures of gingival redness, bleeding on probing, plaque accumulation and suppuration, as well as duplicate measures of pocket depth and attachment level, were made at 6 sites per tooth. The % of sites colonized by each species (prevalence) was computed for each subject. Differences in prevalence and levels among groups were sought using the Kruskal-Wallis test. Commonly detected species, such as Actinomyces naeslundii genospecies 2, Streptococcus sanguis and Streptococcus oralis did not differ significantly among subject groups. After adjusting for multiple comparisons, 4 species were significantly elevated and at greater prevalence in the periodontitis group. Mean % of sites (+/-SEM) colonized by Bacteroides forsythus was 10+/-3, 12+/-2 and 40+/-2 (p<0.001) for healthy, elder and periodontitis groups respectively. The odds ratio was 14.4:1 that a subject had periodontitis when B. forsythus was detected at > or = 5% of sampled sites. Mean prevalence for Porphyromonas gingivalis in healthy, elder and periodontitis subjects was 4+/-2, 5+/-2 and 23+/-2 respectively (p<0.001); for Treponema denticola 12+/-4, 10+/-3 and 30+/-2 (p<0.001) and for Selenomonas noxia 6+/-2, 7+/-2 and 19+/-2 (p<0.01). Similar differences among subject groups were observed when only sites with PD 0-4 mm were analyzed. The data suggest an etiologic role for B. forsythus, P. gingivalis, T. denticola and S. noxia in adult periodontitis.

Actinomyces↗
PubMed1998

Serum antibodies reacting with subgingival species in refractory periodontitis subjects.

The purpose of this investigation was to compare the levels of serum IgG antibody to 85 subgingival species in 32 refractory periodontitis, 56 successfully treated, and 33 periodontally healthy subjects. Refractory subjects showed mean full mouth attachment loss and/or >3 sites showing attachment loss >2.5 mm within 1 year after 2 treatment modalities, scaling and root planing and surgery plus systemically administered tetracycline. Successfully-treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm, 1 year post-therapy. Periodontally healthy subjects exhibited no pocket or attachment level >3 mm, and no evidence of progressing attachment loss during 1 year of monitoring. Baseline serum was obtained from each subject and tested against 85 subgingival species, including reference strains and strains isolated from refractory subjects, using checkerboard immunoblotting. Significance of differences in levels of serum antibody among groups were sought using the Kruskal-Wallis test. Refractory subjects constituted a heterogeneous group based on their serum antibody response to subgingival species. Some individuals had antibody reactions to many subgingival species, while other subjects showed fewer or low numbers of responses. On average, refractory subjects exhibited higher numbers and levels of serum antibody reactions to a wide range of subgingival species than successfully treated or periodontally healthy subjects. Differences in serum antibody among clinical groups were more striking at higher threshold levels of antibody (>50 microg/ml and > 100 microg/ml). The data showed that a subject was 10.1 x more likely to be refractory if the subject exhibited antibody reactions with >9 subgingival species at >50 microg/ml (p<0.001, after adjusting for multiple comparisons). Serum antibody to a subset of the test species differed among the clinical groups. Porphyromonas gingivalis, Bacteroidesforsythus, and some strains isolated from refractory subjects (a novel Neisseria sp., Enterococcus faecalis, Prevotella loescheii and Prevotella oulora) elicited high serum antibody in the successfully treated and refractory subjects. High levels of serum antibody to a Microbacterium lacticum-like organism, Streptococcus oralis, Streptococcus constellatus, Actinobacillus actinonmycetemcomitans serotype c and Haemophilus aphrophilus significantly increased the likelihood of a subject being refractory to conventional periodontal therapy.

Adult↗
PubMed1997

Turnover of F1F0-ATP synthase subunit 9 and other proteolipids in normal and Batten disease fibroblasts.

Fibroblasts derived from patients with late infantile neuronal ceroid lipofucsinosis (NCL) and from a mouse model of NCL are similar to cells in intact animals in that they accumulate subunit 9 of mitochondrial F1F0-ATP synthase (F-ATPase) (Tanner, A., Dice, J.F., Cell Biol. Int. 19 (1995) 71-75). We now report no differences in the synthetic rates of F-ATPase subunit 9 in such affected cells when compared to control cells. However, the degradation rates of F-ATPase subunit 9 are reduced in both the affected human and mouse cells. This reduced degradation applies only to subunit 9 and the homologous vacuolar ATPase subunit among five distinct, reproducible proteolipid bands analyzed. Approximately 15% of newly synthesized F-ATPase subunit 9 is rapidly degraded in control cells, but this rapidly degraded component is absent in both the human and mouse NCL fibroblasts. At confluence, when the accumulated F-ATPase subunit 9 transiently disappears from human NCL fibroblasts, there is an increased degradation of all proteolipids. The pathway of degradation that is enhanced at confluence is likely to correspond to lysosomal macroautophagy. We confirmed that lysosomes were able to degrade F-ATPase subunit 9 after endocytosis of radiolabeled mitochondria. Human NCL fibroblasts were less active than control cells in this lysosomal degradation of endocytosed F-ATPase subunit 9. However, this difference was not specific for F-ATPase subunit 9 since it also applied to total endocytosed mitochondrial protein. We conclude that degradation of F-ATPase subunit 9 can occur by multiple pathways and that a mitochondrial pathway of proteolysis is defective in the late infantile human and mouse forms of NCL.

Animals↗
PubMed1997

Dental implant infections.

Dental implants provide a restorative tool to support crowns, bridge abutments, and removable dentures. Osseointegrated implants are titanium posts that are surgically implanted in alveolar bone. A tight immobile bond (osseointegration) forms between bone and titanium, and prosthetic and restorative fixtures are attached to the implants. Titanium implants differ from natural teeth, which may make them more susceptible to mechanical stress. A small proportion of implants are not successful and may fail due to infection. The microbiota of implants is similar to that of teeth in similar clinical states. Implants that fail because of mechanical stress are colonized by species associated with healthy teeth. Infected implants are colonized by subgingival species, including Porphyromonas gingivalis, Bacteroides forsythus, Fusobacterium nucleatum, Campylobacter gracilis, Streptococcus intermedius, and Peptostreptococcus micros. Different patients may be colonized by different microbial complexes, indicating that optimal treatment should be directed to the specific infection.

Bacterial Infections↗
PubMed1997

Nitric oxide attenuates interleukin 2-induced lung injury.

BACKGROUND: The pathogenesis of interleukin (IL) 2-induced vascular leak syndrome may be related to neutrophil-mediated endothelial injury. Nitric oxide inhibits neutrophil superoxide anion synthesis and adherence to endothelial cells. The role of systemic nitric oxide in preventing IL-2-induced lung injury was studied in an experimental model. METHODS: Sprague-Dawley rats (seven per group) were randomized to control, IL-2 treatment (1 x 10(6) units), and IL-2 with sodium nitroprusside 0.2 mg/kg. Lung injury was measured by estimation of extravascular lung water (wet:dry weight) and bronchoalveolar lavage (BAL) protein concentration, and by histological findings. Neutrophil infiltration was evaluated by measuring myeloperoxidase activity and BAL neutrophil concentration. RESULTS: IL-2 produced significant lung damage characterized by leucocyte sequestration (increased myeloperoxidase and BAL neutrophil concentrations), pulmonary congestion and microvascular protein leakage (increased wet:dry weight ratio and BAL protein concentration). This injury was reduced significantly by the addition of sodium nitroprusside, the nitric oxide donor. CONCLUSION: Nitric oxide reduces IL-2-induced lung injury.

Animals↗
PubMed1996

Reversible colostomy--what is the outcome?

PURPOSE: The trend toward avoidance of a colostomy at both elective and emergency large-bowel surgery is partly driven by the perceived morbidity and low closure rates of temporary stomas. The aim of this study was to examine whether significant colostomy-related morbidity remains persistently high. METHODS: To examine this, we reviewed 120 patients with a potentially reversible colostomy performed during either elective or emergency large-bowel surgery during a seven-year period. RESULTS: Forty-seven patients underwent elective and 73 patients underwent emergency colonic or colorectal resection. Fifty-eight patients had colorectal carcinoma (48.3 percent), diverticular disease accounted for 39 patients (32.5 percent), and a miscellaneous group of 23 patients (19.2 percent) made-up the remainder. Seven patients died, all in the emergency group (9.6 percent). Colostomy-related morbidity, which included stenosis, retraction, prolapse, and hernia formation, occurred in 19.2 percent of patients, with no difference between the elective (14.9 percent) and emergency (21.9 percent) groups or underlying pathologic condition. Colostomy closure was performed initially in 71 patients (59.2 percent). Highest closure rates occurred in the diverticular group (84.6 percent), followed by the colorectal carcinoma group (48.3 percent), and then the miscellaneous group (43.5 percent). One patient died undergoing colostomy closure, and complications occurred in 25 patients (35.2 percent), requiring fashioning of a second colostomy in eight patients, two of whom were closed. Final colostomy closure rate was 54.2 percent. CONCLUSIONS: This study confirms the contention that both formation and closure of defunctioning colostomies are associated with significant complications; furthermore, approximately one-half of patients will not have their colostomy closed.

Colonic Diseases↗
PubMed1996

Frictional action at lower limb/prosthetic socket interface.

The frictional action at stump/socket interface is discussed by a simplified model and finite element model analyses and clinical pressure measurements. The friction applied to the stump skin produces stresses within tissue and these stresses may damage the tissues and affect their normal functions. The combination of normal and shear stresses is considered to be a critical factor leading to amputee's discomfort and tissue damage. However, friction at the stump/socket interface has a beneficial action. A simplified residual limb model and a finite element model using real geometry have been developed to analyse the support action of friction. Both results show that the friction plays a critical role both in supporting the load of the amputee's body during the support phase of the gait cycle and in preventing the prosthesis from slipping off the limb during swing phase. Pressure at the below-knee socket during walking were measured with conditions of different friction. The results reveal that a larger pressures was produced at the lubricated interface than at the normal interface. A proper choice of coefficient of friction will balance the requirements of relief of load stress and reduction of slip with the general ability to support loads.

Amputation Stumps↗
PubMed1996

Clinical, microbiological and immunological profile of healthy, gingivitis and putative active periodontal subjects.

Thirteen periodontally healthy subjects were monitored clinically for 6-12 months. Clinical measurements at 6-weekly intervals included duplicate PD measurements, presence of plaque, redness, and bleeding on probing. Baseline measurements consisted of 2 visits 1 wk apart. Microbial samples were taken from 11 of the subjects who had completed at least 8 months of monitoring. Levels of serum antibodies to 12 periodontal species were determined from 10 subjects. Standard deviations of replicate PD measurements, computed for each subject, ranged from 0.2-0.3 mm over the monitoring period. Plaque and redness increased during monitoring, and showed a weak association with PD change. Baseline and follow-up distributions of PD changes indicated that changes of > 1.5 mm could reasonably be considered to represent active sites. Five subjects demonstrated at least 1 site deepening by 1.5 mm over the period monitored, and these were considered putative active subjects. Sites from 2 subjects showed PD increases in the 6 wk just before sampling, and these were considered to represent active sites. Species associated with putative active subjects included Actinomyces naeslundii, Veillonella parvula, Selenomonas noxia and Prevotella nigrescens. Streptococcus sanguis, S. gordonii and Peptostreptococcus micros were associated with inactive subjects. S. gordonii and S. oralis were associated with health, whereas P. nigrescens was associated with gingivitis. Elevated serum antibodies were detected to A. actinomycetemcomitans in 4 subjects. The predominant microbiota of putative active subjects included some species previously associated with gingivitis, and some species previously associated with progressing periodontitis.

Adult↗
PubMed1996

Rapid characterization of periodontal bacterial isolates by using fluorogenic substrate tests.

Eighty-nine species of subgingival bacteria, represented by 121 reference strains and 892 patient isolates, including gram-negative, gram-positive, aerobic, facultatively anaerobic, microaerophilic, and anaerobic species, were characterized with a panel of fluorogenic, 4-methylumbelliferyl-linked substrate tests. Identifications of all patient isolates were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell proteins relative to reference strains. Characteristic profiles of positive fluorogenic reactions differentiated most of the species, including five Porphyromonas species, six pigmenting and five nonpigmenting Prevotella species, Bacteroides forsythus, three Capnocytophaga species, six Actinomyces species, four Propionibacterium species, and eight Streptococcus species. Two mannoside isomers differentiated Actinomyces israelii and Actinomyces gerencseriae. In addition to Porphyromonas gingivalis, B. forsythus, and Capnocytophaga species, Fusobacterium alocis, Actinomyces odontolyticus, Actinomyces meyeri, and Bifidobacterium dentium were all positive for so-called trypsin-like activity. Fusobacterium nucleatum, Eikenella corrodens, Actinobacillus actinomycetemcomitans, and Campylobacter species were nonreactive with the carbohydrate-based substrates tested. Fluorogenic substrate tests provided a sensitive and simple method for biochemical characterization that could presumptively identify to species level most subgingival isolates within 4 h. The method was ideal for rapidly obtaining presumptive identifications of isolates prior to confirming identifications by definitive methods, such as SDS-PAGE.

Bacteria↗
PubMed1996

Male duct ectasia associated with HIV infection.

The incidence of male duct ectasia (periductal mastitis) is extremely rare, only eight cases having been reported. The underlying cause (as in females) is uncertain. Two cases in HIV positive males of recurrent unilateral nipple lesions are reported with histology consistent with duct ectasia. At presentation neither patient had an AIDS defining illness. An impaired immunity secondary to HIV infection may result in an increased susceptibility to repeated nipple infections, and the clinical as well as histological features of duct ectasia. The consideration of HIV infection in future cases of male duct ectasia may be warranted.

Adult↗
PubMed1996

Propranolol reduces the anxiety associated with day case surgery.

OBJECTIVE: To find out if propranolol, a non-cardioselective beta-blocker, can reduce the anxiety associated with day case surgery. DESIGN: Prospective randomized double blind trial. SETTING: University hospital, Ireland. SUBJECTS: An unselected group of 53 patients undergoing day case surgery. INTERVENTION: Subjects randomised to receive either propranolol (10 mg) or placebo on the morning of operation. MAIN OUTCOME MEASURES: Blood pressure; pulse, anxiety, pain score and patient satisfaction. RESULTS: Mean (SD) Hospital Anxiety and Depression score was significantly lower in the propranolol group than in the control group (2.5 (0.7) compared with 4.6 (0.7), p < 0.0001) before discharge. CONCLUSION: A low dose of propranolol given on the morning of day case surgery significantly reduced patients' anxiety.

Adrenergic beta-Antagonists↗
PubMed1995

Batten disease fibroblasts in culture accumulate mitochondrial ATP synthase subunit 9.

Batten Disease is a lysosomal storage disease in which the major component that accumulates is subunit 9 of mitochondrial ATP synthase. Whether or not fibroblasts in culture exhibit this phenotype is controversial. We show that fibroblasts from a human Batten Disease patient and from a mouse model of this disease exhibit autofluorescent inclusion bodies. We also demonstrate that levels of ATP synthase subunit 9 are elevated in these diseased fibroblasts when compared to control cells. However, the exact growth state of the human fibroblasts was critical, and this factor probably accounts for discrepencies in the literature.

Animals↗
PubMed1995

[Coraco-clavicular screw fixation: a simple treatment of acromioclavicular joint dislocation].

A series of 41 patients (average age 34 years) with acute acromio-clavicular joint separation were treated from 1985 to 1993 by temporary coraco-clavicular transfixation screw. The screw secures the anatomical position of the clavicle until the coraco-clavicular and the acromio-clavicular ligaments are healed. Follow-up was possible in 25 patients. The examination consisted in clinical and radiological evaluations, including assessment of subjective well-being: 24 patients were satisfied, while 1 patient complained of minor pain at work. Follow-up X-rays revealed mild subluxation of the acromio-clavicular joint in 5 patients and slight acromio-clavicular diastasis in 2. In 10 patients we found ligamentous calcifications. All patients had normal shoulder function. Seven patients had enlarged scars. Our good results indicate that this procedure can be recommended.

Acromioclavicular Joint↗