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Notes: Background, aim: The present study describes (i) the natural distribution of the three putative periodontopathogens Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans in an Australian population and (ii) the relationship between these organisms, pocket depths and supragingival plaque scores.Methods: Subgingival plaque was collected from the shallowest and deepest probing site in each sextant of the dentition. In total, 6030 subgingival plaque samples were collected from 504 subjects. An ELISA utilising pathogen-specific monoclonal antibodies was used to quantitate bacterial numbers.Results:: A. actinomycetemcomitans was the most frequently detected organism (22.8% of subjects) followed by P. gingivalis and P. intermedia (14.7% and 9.5% of subjects respectively). The majority of infected subjects (83%) were colonised by a single species of organism. A. actinomycetemcomitans presence was over-represented in the youngest age group but under-represented in the older age groups. Conversely, P. gingivalis and P. intermedia presence was under-represented in the youngest age group but over-represented in the older age groups. Differing trends in the distribution of these bacteria were observed between subjects depending upon the site of the infection or whether a single or mixed infection was present; however, these differences did not reach significance. Bacterial presence was strongly associated with pocket depth for both A. actinomycetemcomitans and P. gingivalis. For A. actinomycetemcomitans, the odds of a site containing this bacterium decrease with deeper pockets. In contrast, for P. gingivalis the odds of a site being positive are almost six times greater for pockets 〉3 mm than for pockets 〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE281212:les" location="les.gif"/〉3 mm. These odds increase further to 15.3 for pockets deeper than 5 mm. The odds of a site being P. intermedia positive were marginally greater (1.16) for pockets deeper than 3 mm.Conclusions: This cross-sectional study in a volunteer Australian population, demonstrated recognised periodontal pathogens occur as part of the flora of the subgingival plaque. Prospective longitudinal studies are needed to examine the positive relationship between pocket depth and pathogen presence with periodontal disease initiation and/or progression.

Notes: 1. In 14 hypertensive patients aldosterone/cortisol ratio was always lower in a peripheral vein or low IVC than in either adrenal vein. In four patients with a right-sided aldosterone-producing adenoma (APA), the aldosterone/cortisol ratio in peripheral vein was always higher than in the left adrenal vein. If only the left adrenal vein is cannulated, right-sided APA can still be diagnosed with certainty.2. In three patients with glucocorticoid-suppressible hyperaldosteronism, urinary excretion of both 18-oxocortisol and 18-hydroxycortisol was elevated. In four patients with APA excretion of 18-oxocortisol was elevated. In two of three patients with bilateral adrenal hyperplasia (BH), excretion of both steroids was normal.3. 75Se-selenomethylcholesterol scanning correctly lateralized five APA, but falsely lateralized a patient with BH. Results with CT scans were often misleading.

Notes: 1. The ratio of aldosterone to renin in plasma was measured in samples collected from 79 hypertensive patients.2. Eighteen patients with primary aldosteronism had ratios ranging from 25 to 677 (mean 183) when measured on 34 occasions, while 16 normal subjects had ratios of 3.3–21 (mean 11.3).3. Of the remaining 61 patients with ratios ranging from 1.8 to 184, 15 patients have ratios greater than 25 and are under investigation for primary aldosteronsim, which appears highly likely in five and has been excluded in two.4. The aldosterone/renin ratio appears promising as a screening test for primary aldosteronism. Consistency and the effects of sodium and potassium balance and of antihypertensive medications require further study.

Notes: 1. Saline infusion was performed in normal subjects, in essential hypertensives and in patients with aldosterone-producing adenoma (APA), with serial measurements of plasma aldosterone, cortisol and atrial natriuretic peptide (ANP). The effect of recumbency alone was also observed in the normal subjects.2. Plasma aldosterone after saline infusion was less than 7 ng per 100 ml in the essential hypertensives and normal subjects, but greater than 9 ng per 100 ml in the patients with APA.3. The aldosterone/cortisol ratio in normal subjects and in essential hypertensives was unchanged or fell during saline infusion, but rose in five of eight patients with APA.4. Thus, an increase in aldosterone/cortisol ratio after saline infusion appears to be diagnostic of APA, but its absence does not exclude it.

Notes: 1. Two males with glucocorticoid-suppressible hyperaldosteronism had hyperaldosteronism, hypertension and hypokalaemia corrected by continuous administration of physiological doses of dexamethasone for more than a year.2. During long-term dexamethasone treatment:(a) Plasma renin activity increased from subnormal to high normal levels, with normal posture-mediated increases;(b) Plasma aldosterone became responsive to angiotensin infusion, a new observation;(c) A fall in plasma aldosterone between 0800 h (recumbent) and 1000 h (upright) was replaced by a rise;(d) Plasma aldosterone became suppressible with salt loading.3. These findings are consistent with a shift to more normal control of aldosterone by renin-angiotensin, once abnormal responsiveness to ACTH has been nullified.

Notes: 1. A subgroup of patients with aldosterone-producing adenoma (APA) have been identified who lack many of the biochemical features regarded as characteristic of APA and used to distinguish APA from bilateral adrenal hyperplasia.2. In these patients, aldosterone is responsive to infused angiotensin II (angiotensin-responsive APA), which explains their uncharacteristic responses to upright posture, saline infusion and fludrocortisone acetate administration.3. The angiotensin-responsiveness of these patients may derive from the contra-lateral adrenal gland, since renin levels are less completely suppressed in angiotensin-responsive APA than in angiotensin-unresponsive APA.4. However, while the excretion of 18-oxo-cortisol was consistently increased in angiotensin-unresponsive APA, it was normal in angiotensin-responsive APA, consistent with biochemical and biosynthetic distinctiveness residing in the tumours.5. Angiotensin-responsive APA should always be considered as an alternative diagnosis to bilateral hyperplasia causing primary aldosteronism.

Notes: Objectives: The aim of the present study was to determine the effect of unsupervised, long-term use of a 0.3% triclosan/2% copolymer dentifrice on the progression of periodontal disease in a general adult population.Methods: Five hundred and four volunteers were enrolled in a double-blind, controlled clinical trial. Participants were matched for disease status, plaque index, age and gender. At the baseline examination, probing pocket depths and relative attachment levels were recorded and participants were assigned to either the test or control group. Re-examinations took place after 6, 12, 24, 36, 48 and 60 months. Subgingival plaque samples were collected at each examination and assayed for Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia. A generalised linear model was used to analyse the data, with a number of covariates thought to influence the responses included as the possible confounding effects.Results: The triclosan/copolymer dentifrice had a significant effect in subjects with interproximal probing depths ≥3.5 mm, where it significantly reduced the number of sites with probing depths ≥3.5 mm at the following examination, when compared with the control group (p〈0.001). Furthermore, this effect increased with increasing numbers of affected sites. There was no effect of the triclosan/copolymer dentifrice in individuals without probing depths ≥3.5 mm at the previous examination. Other factors significantly affecting probing pocket depths (PPD) included increasing age, smoking and presence of P. gingivalis. PPD ≥3.5 mm were positively associated with loss of attachment some 2 years later.Conclusion: This study showed that in a normal adult population, unsupervised use of a triclosan/copolymer dentifrice is effective in slowing the progression of periodontal disease.

Notes: Objectives: The present study describes the natural history of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Prevotella intermedia over a 5-year period and the effect of a triclosan/copolymer dentifrice on these organisms in a normal adult population.Material and Methods: Subgingival plaque samples were collected from 504 adult volunteers. Probing pocket depths (PPD) and relative attachment levels were measured using an automated probe. Participants were matched for disease status (CPI), plaque index, age and gender, and allocated to receive either a triclosan/copolymer or placebo dentifrice. Re-examination and subgingival plaque sampling was repeated after 1, 2, 3, 4 and 5 years. P. gingivalis, A. actinomycetemcomitans and P. intermedia were detected and quantitated using an enzyme linked immunosorbent assay. Logistic regression and generalised linear modelling were used to analyse the data.Results: This 5-year longitudinal study showed considerable volatility in acquisition and loss (below the level of detection) of all three organisms in this population. Relatively few subjects had these organisms on multiple occasions. While P. gingivalis was related to loss of attachment and to PPD ≥3.5 mm, there was no relationship between A. actinomycetemcomitans or P. intermedia and disease progression over the 5 years of the study. Smokers with P. gingivalis had more PPD ≥3.5 mm than smokers without this organism. There was no significant effect of the triclosan dentifrice on P. gingivalis or A. actinomycetemcomitans. Subjects using triclosan were more likely to have P. intermedia than those not using the dentifrice; however this did not translate into these subjects having higher levels of P. intermedia and its presence was uniform showing no signs of increasing over the course of the study.Conclusion: The present 5-year longitudinal study has shown the transient nature of colonisation with P. gingivalis, A. actinomycetemcomitans and P. intermedia in a normal adult population. The use of a triclosan-containing dentifrice did not lead to an overgrowth of these organisms. The clinical effect of the dentifrice would appear to be independent of its antimicrobial properties.