Continuing education: The 1998 survey of the Royal Australasian College of Dental Surgeons

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: Continuing education (CE) is an essential professional activity. In the last decade, CE has been actively pursued by the medical profession in Australia and abroad. However, the uptake of CE in dentistry has been much slower and there is minimal Australian data on dental CE. Methods: To determine the level of CE activity, in 1998, postal questionnaires were sent to all fellows of the Royal Australasian College of Dental Surgeons. The responses were analysed. Results: There was a high reponse rate (90 per cent) but a moderate usable rate (54 per cent). The results show a biphasic distribution between high and low CE activity. The average amount of activity of those involved in CE was 116 hours per year, above the usually accepted minimum of 100 hours/year. Some groups, particularly members of the specialist divisions of oral and maxillofacial surgeons (215 hours) and periodontists (205 hours), have high levels of CE. However, approximately 25 per cent of college fellows reported little or no CE activity. The survey revealed that inactive fellows are more likely to be older and in general practice. Inactive fellows were also tardy in replying to the questionnaire. Conclusion: The high activity CE group needs to be recognised and encouraged to continue. Specific plans to help the low CE activity group should be developed. Although these findings relate directly to the Royal Australasian College of Dental Surgeons, they are presented as they have implications for the dental profession at large.P Sambrook, D Thomson, R Bastiaan and A Gos

Sequence variation in the haemagglutinin-neuraminidase gene of human parainfluenza virus type 3 isolates in the UK

The sequence variation in a 934 base-pair region of the gene encoding the haemagglutinin-neuraminidase of five human parainfluenza virus type 3 (HPIV3) isolates was determined together with that of a prototype UK strain. All of the clinical isolates were from the Manchester area of the UK and were obtained in 1990. 1991 and 1993. The gene segment was amplified by the polymerase chain reaction using HPIVB-specific oligonucleotide primers. The nucleotide homology of the strains was high, around 99% and specific differences in the UK sequences when compared with that of the US prototype strain were identified. In addition, a number of isolate-specific differences were seen. No correlation was detected between the observed nucleotide mutations and the year of isolation, which supports the hypothesis that HPIV3 shows cocirculation of a heterogeneous population of viruses rather than varying with time in a linear fashion. However, the data suggested that geographically-defined genetic lineages of HPIV3 may exist

A national survey of the chemotherapy regimens used to treat small cell lung cancer (SCLC) in the United Kingdom

Many chemotherapy regimens are used for treating SCLC in the United Kingdom, but it is not known, in any detail, which regimens are used, by which specialists, for which types of patient. We conducted a survey among all medical and clinical oncologists, respiratory physicians and general physicians with respiratory interest in the United Kingdom to find out. The questionnaire asked for the number of SCLC patients treated annually; how many were given chemotherapy; the drugs, doses and schedules chosen according to prognostic group (as defined by the clinician); and the reasons for choice of regimen. 1214 questionnaires were sent out, and responses were received from 1070 (88%) clinicians; 266 (25%) of these treated SCLC with chemotherapy. Of 4674 patients given chemotherapy annually, 36% were given it by clinical oncologists, 30% by medical oncologists, 27% by respiratory physicians, and 7% by general physicians. In all, 34 regimens were reported with 151 different combinations of dose and schedule. In 2311 good prognosis patients, 23 regimens were used, the commonest being ACE (doxorubicin, cyclophosphamide, etoposide), ICbE (ifosfamide, carboplatin, etoposide), CAV (cyclophosphamide, doxorubicin, vincristine), CbE (carboplatin, etoposide), and PE (cisplatin, etoposide). In 1517 poor prognosis patients, 21 regimens were used, the commonest being CAV, EV (etoposide, vincristine), CbE, CAV alternating with PE, and oral etoposide. 452 patients were treated regardless of prognosis and for 219 no prognostic criteria were specified. The remaining 175 were given second-line chemotherapy or were given regimens chosen to avoid toxicity or because of intercurrent disease or other reasons. The main reasons affecting choice of regimen were routine local practice, patients' convenience, quality of life considerations, trial results and cost. The results show wide variation in routine practice and will be useful in reporting and planning clinical trials and in deciding on local treatment policies. © 2001 Cancer Research Campaign http://www.bjcancer.co

The Effect of Demineralization and Remineralization Cycles on the Bond Strength of Resin Composite to Enamel

Toothwear is a growing concern, particularly in young adults. Prevention strategies remain of utmost importance and may involve the use of remineralising agents. If restorative treatment is indicated, adhesive techniques are recommended. It is unknown whether remineralising agents affect adhesion. METHOD: 77 bovine incisors were subjected to simulated toothwear by erosion (0.3% citric acid) and abrasion (oscillating toothbrush). Samples were randomly arranged into 5 test and 2 control groups (n=11). Each test group had a remineralising agent applied. Subsequently, composite was bonded to each sample and subjected to shear bond testing. Shear bond strength, mode of failure and enamel surface changes were analysed. RESULTS: There was no statistically significant difference for bond strength between groups (p=0.262). Mode of failure was statistically significant between groups (p⟨0.0001). Qualitative analysis showed a surface layer on samples remineralised by calcium silicate and stannous fluoride. Both groups had more adhesive failures. CONCLUSION: Within the limitations of this study, it can be concluded that the remineralising agents tested do not affect shear bond strength though surface layers created on the enamel influence the mode of failure. These 'sacrificial' surface layers have the potential to protect the underlying enamel structure

Assessing dentists' knowledge and experience in restoring endodontically treated teeth using post & cores

OBJECTIVES: The restoration of endodontically, heavily filled teeth has been a challenge for the dental profession for decades. The aims of this study were to investigate dentists' experience and knowledge in the use of post & core when restoring endodontically treated teeth. METHOD: This was a mixed method study incorporating quantitative and qualitative data collection. An online questionnaire was developed and distributed, comprised of 18 questions. It was calculated that 93 respondents were needed to validate the study of which 60% should meet a minimum knowledge requirement. RESULTS: 173 respondents completed the questionnaire. 109 (63% (95%CI56%,70%) demonstrated proficient knowledge of post & core restorations. Recent graduates were more likely to follow current guidelines (F=4.570: P<0.034). As the age of the respondent increases the number of posts placed (F=18.85; p<0.001) and the perceived confidence level increases (Spearman's Rho 0.43: P<0.01). Experience of postgraduate education also positively influenced clinical confidence. CONCLUSION: The placement of post & cores is influenced by age. Confidence is also influenced by age. More evidence on post usage is required and several questions remain to be answered on what drives decision making and perceived long-term success. CLINICAL SIGNIFICANCE: There is a general acceptance of when a post and core restoration should be used. Clinician experience and age can have an impact on what type of restorations are used. Fibre posts are more commonly used due their accessibility and cost

Hydrodynamic controls on alluvial ridge construction and avulsion likelihood in meandering river floodplains

This is the author accepted manuscript. The final version is available from Geological Society of America via the DOI in this record.Existing models of alluvial stratigraphy often neglect the hydrodynamic controls on channel belt and floodplain sedimentation, and predict avulsion using topographic metrics, such as channel belt super-elevation (the ratio of alluvial ridge height to channel depth). This study provides a first demonstration of the potential for simulating long-term river floodplain evolution (over >500 floods) using a process-based hydrodynamic model. Simulations considered alluvial ridge construction during the period leading up to an avulsion, and assess the controls on avulsion likelihood. Results illustrate that the balance between within-channel and overbank sedimentation exerts a key control on both super-elevation ratios and on the conveyance of water and sediment to the floodplain. Rapid overbank sedimentation creates high alluvial ridges with deep channels, leading to lower apparent super-elevation ratios, and implying a reduced likelihood of avulsion. However, channel deepening also drives a reduction in channel belt–floodplain connectivity, so that conveyance of water to the distal floodplain is concentrated in a declining number of channel breaches, which may favor avulsion. These results suggest that, while super-elevation ratios in excess of a threshold value may be a necessary condition for a meandering river avulsion, the likelihood of avulsion may not be greatest where the super-elevation ratio is maximized. Instead, optimal conditions for avulsion may depend on channel-floodplain hydrodynamic connectivity, determined by the balance between coarse (channel bed–forming) and fine (floodplain-constructing) sediment delivery. These results highlight a need to rethink the representation of avulsion in existing models of alluvial architecture.This work was funded by UK Natural Environment Research Council grants NE/H009108/1 and NE/H007288/1

Role of glucose and CcpA in capsule expression and virulence of Streptococcus suis

Streptococcus suis is one of the most important pathogens in pigs and is also an emerging zoonotic agent. After crossing the epithelial barrier, S. suis causes bacteraemia, resulting in meningitis, endocarditis and bronchopneumonia. Since the host environment seems to be an important regulatory component for virulence, we related expression of virulence determinants of S. suis to glucose availability during growth and to the sugar metabolism regulator catabolite control protein A (CcpA). We found that expression of the virulence-associated genes arcB, representing arcABC operon expression, cps2A, representing capsular locus expression, as well as sly, ofs, sao and epf, differed significantly between exponential and early stationary growth of a highly virulent serotype 2 strain. Deletion of ccpA altered the expression of the surface-associated virulence factors arcB, sao and eno, as well as the two currently proven virulence factors in pigs, ofs and cps2A, in early exponential growth. Global expression analysis using a cDNA expression array revealed 259 differentially expressed genes in early exponential growth, of which 141 were more highly expressed in the CcpA mutant strain 10¿ccpA and 118 were expressed to a lower extent. Interestingly, among the latter genes, 18 could be related to capsule and cell wall synthesis. Correspondingly, electron microscopy characterization of strain 10¿ccpA revealed a markedly reduced thickness of the capsule. This phenotype correlated with enhanced binding to porcine plasma proteins and a reduced resistance to killing by porcine neutrophils. Taken together, our data demonstrate that CcpA has a significant effect on the capsule synthesis and virulence properties of S. suis

Is \gamma-ray emission from novae affected by interference effects in the 18F(p,\alpha)15O reaction?

The 18F(p,\alpha)15O reaction rate is crucial for constraining model predictions of the \gamma-ray observable radioisotope 18F produced in novae. The determination of this rate is challenging due to particular features of the level scheme of the compound nucleus, 19Ne, which result in interference effects potentially playing a significant role. The dominant uncertainty in this rate arises from interference between J\pi=3/2+ states near the proton threshold (Sp = 6.411 MeV) and a broad J\pi=3/2+ state at 665 keV above threshold. This unknown interference term results in up to a factor of 40 uncertainty in the astrophysical S-factor at nova temperatures. Here we report a new measurement of states in this energy region using the 19F(3He,t)19Ne reaction. In stark contrast with previous assumptions we find at least 3 resonances between the proton threshold and Ecm=50 keV, all with different angular distributions. None of these are consistent with J\pi= 3/2+ angular distributions. We find that the main uncertainty now arises from the unknown proton-width of the 48 keV resonance, not from possible interference effects. Hydrodynamic nova model calculations performed indicate that this unknown width affects 18F production by at least a factor of two in the model considered.Comment: 5 pages, 4 figures. Accepted for publication in Phys. Rev. Let

Reliable microsatellite genotyping of the Eurasian badger (Meles meles) using faecal DNA

The potential link between badgers and bovine tuberculosis has made it vital to develop accurate techniques to census badgers. Here we investigate the potential of using genetic profiles obtained from faecal DNA as a basis for population size estimation. After trialling several methods we obtained a high amplification success rate (89%) by storing faeces in 70% ethanol and using the guanidine thiocyanate/silica method for extraction. Using 70% ethanol as a storage agent had the advantage of it being an antiseptic. In order to obtain reliable genotypes with fewer amplification reactions than the standard multiple-tubes approach, we devised a comparative approach in which genetic profiles were compared and replication directed at similar, but not identical, genotypes. This modified method achieved a reduction in polymerase chain reactions comparable with the maximumlikelihood model when just using reliability criteria, and was slightly better when using reliability criteria with the additional proviso that alleles must be observed twice to be considered reliable. Our comparative approach would be best suited for studies that include multiple faeces from each individual. We utilized our approach in a well-studied population of badgers from which individuals had been sampled and reliable genotypes obtained. In a study of 53 faeces sampled from three social groups over 10 days, we found that direct enumeration could not be used to estimate population size, but that the application of mark–recapture models has the potential to provide more accurate results