Amoebic liver abscess - results of a conservative management policy

Objective. To evaluate the safety and efficacy of conservative management of amoebic liver abscesses.Design. A prospective study carried out over a 1-year period.Setting. Inpatients and outpatients in a tertiary referral institution.Subjects. Amoebic liver abscess was diagnosed on clinical, ultrasonographic, and serological features. All patients were treated with metronidazole. The indication for ultrasound guided aspiration of the abscess was failure to improve clinically within 48 - 72 hours.Main outcome measures. Clinical improvement, clinical deterioration and failure of clinical improvement (persistent pain).Results. In total 178 patients (male-to-female ratio 5:1) with 203 abscesses were treated during this period. Of these, 23 patients required  percutaneous aspiration and 150 patients were managed without intervention and clinically resolved spontaneously. Abscesses requiring aspiration tended to be larger than those managed without aspiration (10.7 cm v. 8.2 cm) (p = 0.003). There were no complications following aspiration. Mean hospital stay was longer (12.3 days) for patients who underwent aspiration compared with those who did not (6. 7 days) (p = 0.031). Only 5 patients presented with ruptured abscesses, 1 cutaneously and 4 intraperitoneally, with the only death in this latter category.Conclusion. Conservative medical management of amoebic liver abscess is safe. Percutaneous ultrasound-guided aspiration is indicated only in patients who fail to improve clinically after 48 - 72 hours rather than on rigid criteria

To fill or not to fill: a qualitative cross-country study on dentists' decisions in managing non-cavitated proximal caries lesions

BACKGROUND: This study aimed to identify barriers and enablers for dentists managing non-cavitated proximal caries lesions using non- or micro-invasive (NI/MI) approaches rather than invasive and restorative methods in New Zealand, Germany and the USA. METHODS: Semi-structured interviews were conducted, focusing on non-cavitated proximal caries lesions (radiographically confined to enamel or the outer dentine). Twelve dentists from New Zealand, 12 from Germany and 20 from the state of Michigan (USA) were interviewed. Convenience and snowball sampling were used for participant recruitment. A diverse sample of dentists was recruited. Interviews were conducted by telephone, using an interview schedule based on the Theoretical Domains Framework (TDF). RESULTS: The following barriers to managing lesions non- or micro-invasively were identified: patients' lacking adherence to oral hygiene instructions or high-caries risk, financial pressures and a lack of reimbursement for NI/MI, unsupportive colleagues and practice leaders, not undertaking professional development and basing treatment on what had been learned during training, and a sense of anticipated regret (anxiety about not restoring a proximal lesion in its early stages before it progressed). The following enablers were identified: the professional belief that remineralisation can occur in early non-cavitated proximal lesions and that these lesions can be arrested, the understanding that placing restorations weakens the tooth and inflicts a cycle of re-restoration, having up-to-date information and supportive colleagues and work environments, working as part of a team of competent and skilled dental practitioners who perform NI/MI (such as cleaning or scaling), having the necessary resources, undertaking ongoing professional development and continued education, maintaining membership of professional groups and a sense of professional and personal satisfaction from working in the patient's best interest. Financial aspects were more commonly mentioned by the German and American participants, while continuing education was more of a focus for the New Zealand participants. CONCLUSIONS: Decisions on managing non-cavitated proximal lesions were influenced by numerous factors, some of which could be targeted by interventions for implementing evidence-based management strategies in practice

A coupled natural immobilisation machanism for mercury and selenium in deep-sea sediments.

Abstract—In the succession of redox conditions encountered with increasing depth in sediments, the first major redox change is the oxic/post-oxic boundary. The geochemical behaviour of Hg is investigated in three different deep-sea situations where this boundary has been localised within a narrow depth zone for a sustained period (thousands of years) because of changes in sedimentary accumulation conditions. From previous work it is known that a variety of redox-sensitive elements form diagenetic peak concentrations above and below this boundary. This work shows for the first time that Hg also develops sharp peaks immediately into post-oxic conditions in two different situations where sediments containing trace pyrite have been re-oxidised. The Hg peaks are always closely associated with corresponding Se peaks, and the diagenetic concentrations of both elements are persistent over millions of years on subsequent burial into more reducing conditions. There is an apparent offset in the locations of Hg and Se peaks observed in a continuously accumulated case where Se uptake from bottom waters occurs independently of pyrite formation or re-oxidation, which may be a consequence of a widely spread Se peak. It is proposed that formation of the HgSe species tiemannite is involved, by analogy with selenium ore occurrences and the other elements found immobilised along with Se and Hg in the cases studied. Copyright © 1999 Elsevier Science Ltd 1

A bibliometric analysis of community dentistry and oral epidemiology: fifty years of publications

Objectives In celebration of the journal's 50th anniversary, the aim of the study was to review the whole collection of Community Dentistry and Oral Epidemiology (CDOE) publications from 1973 to 2022 and provide a complete overview of the main publication characteristics. Methods The study used bibliometric techniques such as performance and science mapping analysis of 3428 articles extracted from the Scopus database. The data were analysed using the ‘Bibliometrix’ package in R. The journal's scientific production was examined, along with the yearly citation count, the distribution of publications based on authors, the corresponding author's country and affiliation and citation count, citing source and keywords. Bibliometric network maps were constructed to determine the conceptual, intellectual and social collaborative structure over the past 50 years. The trending research topics and themes were identified. Results The total number of articles and average citations has increased over the years. D Locker, AJ Spencer, A Sheiham and WM Thomson were the most frequently published authors, and PE Petersen, GD Slade and AI Ismail published papers with the highest citations. The most published countries were the United States, United Kingdom, Brazil and Canada, frequently engaging in collaborative efforts. The most common keywords used were ‘dental caries’, ‘oral epidemiology’ and ‘oral health’. The trending topics were healthcare and health disparities, social determinants of health, systematic review and health inequalities. Epidemiology, oral health and disparities were highly researched areas. Conclusion This bibliometric study reviews CDOE's significant contribution to dental public health by identifying key research trends, themes, influential authors and collaborations. The findings provide insights into the need to increase publications from developing countries, improve gender diversity in authorship and broaden the scope of research themes

Gender inequities in dental research publications: findings from 20 years

Background: The first steps towards gender equity in science are measuring the magnitude of inequity and increasing awareness of the problem. Objectives: To describe trends in gender disparities in first and last authorship in the most cited dental publications and general dental literature over a 20-year period. Methods: Articles and bibliometric data were retrieved from the Scopus database for the period 1996 to 2015. Two groups of 1000 articles each were retrieved: a random sample and another sample of top-cited articles for each year. The gender of the first and last author of each publication was manually identified. When this was not possible, we used an online software platform (https://genderize.io/). Descriptive analyses identified the proportion of women first and last authors in both samples, stratifying by dental discipline and geographic region. Trends were ascertained by frequency metrics across years. Gender disparity was observed in both first and last authorship, with a larger gap being observed in the top-cited sample. Results: Women led 28.4% and 20.3% of articles in the random and top-cited samples, respectively. A similar pattern was observed for the last authorship group (22.1% and 16.1%, respectively). An increasing trend in the proportion of articles led by women over time was observed in both samples. This increase was larger in the top-cited sample (from 15.0% in 1996–2000 to 25.1% in 2015) than in the random sample (from 26.3% in 1996–2000 to 33.2% in 2011). Conclusions: Clear gender disparities in dental research publications in the last 20 years were identified in both general and top-cited manuscripts, across dental disciplines, across countries, across first and last authorship, and over time. It is paramount that actions are taken to attract, retain and promote women in science, as well as to monitor and ensure progress towards gender equity

Psychometric assessment of the short-form Child Perceptions Questionnaire: an international collaborative study.

OBJECTIVE: To examine the factor structure and other psychometric characteristics of the most commonly used child oral-health-related quality-of-life (OHRQoL) measure (the 16-item short-form CPQ11-14 ) in a large number of children (N = 5804) from different settings and who had a range of caries experience and associated impacts. METHODS: Secondary data analyses used subnational epidemiological samples of 11- to 14-year-olds in Australia (N = 372), New Zealand (three samples: 352, 202, 429), Brunei (423), Cambodia (244), Hong Kong (542), Malaysia (439), Thailand (220, 325), England (88, 374), Germany (1055), Mexico (335) and Brazil (404). Confirmatory factor analysis (CFA) was used to examine the factor structure of the CPQ11-14 across the combined sample and within four regions (Australia/NZ, Asia, UK/Europe and Latin America). Item impact and internal reliability analysis were also conducted. RESULTS: Caries experience varied, with mean DMFT scores ranging from 0.5 in the Malaysian sample to 3.4 in one New Zealand sample. Even more variation was noted in the proportion reporting only fair or poor oral health; this was highest in the Cambodian and Mexican samples and lowest in the German sample and one New Zealand sample. One in 10 reported that their oral health had a marked impact on their life overall. The CFA across all samples revealed two factors with eigenvalues greater than 1. The first involved all items in the oral symptoms and functional limitations subscales; the second involved all emotional well-being and social well-being items. The first was designated the 'symptoms/function' subscale, and the second was designated the 'well-being' subscale. Cronbach's alpha scores were 0.72 and 0.84, respectively. The symptoms/function subscale contained more of the items with greater impact, with the item 'Food stuck in between your teeth' having greatest impact; in the well-being subscale, the 'Felt shy or embarrassed' item had the greatest impact. Repeating the analyses by world region gave similar findings. CONCLUSION: The CPQ11-14 performed well cross-sectionally in the largest analysis of the scale in the literature to date, with robust and mostly consistent psychometric characteristics, albeit with two underlying factors (rather than the originally hypothesized four-factor structure). It appears to be a sound, robust measure which should be useful for research, practice and policy

The calibration of the Sudbury Neutrino Observatory using uniformly distributed radioactive sources

The production and analysis of distributed sources of 24Na and 222Rn in the Sudbury Neutrino Observatory (SNO) are described. These unique sources provided accurate calibrations of the response to neutrons, produced through photodisintegration of the deuterons in the heavy water target, and to low energy betas and gammas. The application of these sources in determining the neutron detection efficiency and response of the 3He proportional counter array, and the characteristics of background Cherenkov light from trace amounts of natural radioactivity is described.Comment: 24 pages, 13 figure

Structural Determinants and Children's Oral Health: A Cross-National Study

Much research on children's oral health has focused on proximal determinants at the expense of distal (upstream) factors. Yet, such upstream factors-the so-called structural determinants of health-play a crucial role. Children's lives, and in turn their health, are shaped by politics, economic forces, and social and public policies. The aim of this study was to examine the relationship between children's clinical (number of decayed, missing, and filled teeth) and self-reported oral health (oral health-related quality of life) and 4 key structural determinants (governance, macroeconomic policy, public policy, and social policy) as outlined in the World Health Organization's Commission for Social Determinants of Health framework. Secondary data analyses were carried out using subnational epidemiological samples of 8- to 15-y-olds in 11 countries ( N = 6,648): Australia (372), New Zealand (three samples; 352, 202, 429), Brunei (423), Cambodia (423), Hong Kong (542), Malaysia (439), Thailand (261, 506), United Kingdom (88, 374), Germany (1498), Mexico (335), and Brazil (404). The results indicated that the type of political regime, amount of governance (e.g., rule of law, accountability), gross domestic product per capita, employment ratio, income inequality, type of welfare regime, human development index, government expenditure on health, and out-of-pocket (private) health expenditure by citizens were all associated with children's oral health. The structural determinants accounted for between 5% and 21% of the variance in children's oral health quality-of-life scores. These findings bring attention to the upstream or structural determinants as an understudied area but one that could reap huge rewards for public health dentistry research and the oral health inequalities policy agenda

A Measurement of Time-Averaged Aerosol Optical Depth using Air-Showers Observed in Stereo by HiRes

Air fluorescence measurements of cosmic ray energy must be corrected for attenuation of the atmosphere. In this paper we show that the air-showers themselves can yield a measurement of the aerosol attenuation in terms of optical depth, time-averaged over extended periods. Although the technique lacks statistical power to make the critical hourly measurements that only specialized active instruments can achieve, we note the technique does not depend on absolute calibration of the detector hardware, and requires no additional equipment beyond the fluorescence detectors that observe the air showers. This paper describes the technique, and presents results based on analysis of 1258 air-showers observed in stereo by the High Resolution Fly's Eye over a four year span.Comment: 7 pages, 3 figures, accepted for publication by Astroparticle Physics Journa