Robotic colon surgery in obese patients: a systematic review and meta-analysis

BACKGROUND

Colon cancer resection can be technically difficult in the obese (OB) population. Robotic surgery is a promising technique but its benefits remain uncertain in OB patients. The aim of this study is to compare OB versus non-obese (NOB) patients undergoing robotic colon surgery, as well as OB patients undergoing robotic versus open or laparoscopic colonic surgery.

METHODS

A systematic review and meta-analysis was performed. Primary outcome measures included length of stay (LOS), surgical site infection (SSI) rate, complications, anastomotic leak and oncological outcomes.

RESULTS

A total of eight studies were included, with five comparing OB and NOB patients undergoing robotic colon surgery included in meta-analysis. A total of 263 OB patients and 400 NOB patients formed the sample for meta-analysis. There was no significant difference between the two groups in operative time, conversion to open, LOS, lymph node yield, anastomotic leak and postoperative ileus. There was a trend towards a significant increase in overall complications and SSI in the OB group (32.3% OB versus 26.8% NOB for complications, 14.2% OB versus 9.9% NOB for SSI). The three included studies comparing surgical techniques were too heterogeneous to undergo meta-analysis.

CONCLUSION

Robotic colon surgery is safe in obese patients, but high-quality prospective evidence is lacking. Future studies should report on oncological safety and the cost-effectiveness of adopting the robotic technique in these challenging patients.

Enhanced removal of per- and polyfluoroalkyl substances in complex matrices by polyDADMAC-coated regenerable granular activated carbon

Granular activated carbon (GAC) has been used to remove per- and polyfluoroalkyl substances (PFASs) from industrial or AFFF-impacted waters, but its effectiveness can be low because adsorption of short-chained PFASs is ineffective and its sites are exhausted rapidly by co-contaminants. To increase adsorption of anionic PFASs on GAC by electrostatic attractions, we modified GAC's surface with the cationic polymer poly diallyldimethylammonium chloride (polyDADMAC) and tested its capacity in complex water matrices containing dissolved salts and humic acid. Amending with concentrations of polyDADMAC as low as 0.00025% enhanced GAC's adsorption capacity for PFASs, even in the presence of competing ions. This suggests that electrostatic interactions with polyDADMAC's quaternary ammonium functional groups helped bind organic and inorganic ions as well as the headgroup of short-chain PFASs, allowing more overall PFAS removal by GAC. Evaluating the effect of polymer dose is important because excessive addition can block pores and reduce overall PFAS removal rather than increase it. To decrease the waste associated with this adsorption strategy by making the adsorbent viable for more than one saturation cycle, a regeneration method is proposed which uses low-power ultrasound to enhance the desorption of PFASs from the polyDADMAC-GAC with minimum disruption to the adsorbent's structure. Re-modification with the polymer after sonication resulted in a negligible decrease in the sorbent's capacity over four saturation rounds. These results support consideration of polyDADMAC-modified GAC as an effective regenerable adsorbent for ex-situ concentration step of both short and long-chain PFASs from real waters with high concentrations of competing ions and low PFAS loads.

Profiling microbial community structures and functions in bioremediation strategies for treating 1,4-dioxane-contaminated groundwater

Microbial community compositions and functional profiles were analyzed in microcosms established using aquifer materials from a former automobile factory site, where 1,4-dioxane was identified as the primary contaminant of concern. Propane or oxygen biostimulation resulted in limited 1,4-dioxane degradation, which was markedly enhanced with the addition of nutrients, resulting in abundant Mycobacterium and Methyloversatilis taxa and high expressions of propane monooxygenase gene, prmA. In bioaugmented treatments, Pseudonocardia dioxanivorans CB1190 or Rhodococcus ruber ENV425 strains dominated immediately after augmentation and degraded 1,4-dioxane rapidly which was consistent with increased representation of xenobiotic and lipid metabolism-related functions. Although the bioaugmented microbes decreased due to insufficient growth substrates and microbial competition, they did continue to degrade 1,4-dioxane, presumably by indigenous propanotrophic and heterotrophic bacteria, inducing similar community structures across bioaugmentation conditions. In various treatments, functional redundancy acted as buffer capacity to ensure a stable microbiome, drove the restoration of the structure and microbial functions to original levels, and induced the decoupling between basic metabolic functions and taxonomy. The results of this study provided valuable information for design and decision-making for ex-situ bioreactors and in-situ bioremediation applications. A metagenomics-based understanding of the treatment process will enable efficient and accurate adjustments when encountering unexpected issues in bioremediation.

Biodegradation mechanisms of sulfonamides by Phanerochaete chrysosporium - Luffa fiber system revealed at the transcriptome level

The overuse of antibiotics and subsequent enrichment of antibiotic resistant microbes in the natural and built environments is a severe threat to global public health. In this study, a Phanerochaete chrysosporium fungal-luffa fiber system was found to efficiently biodegrade two sulfonamides, sulfadimethoxine (SDM) and sulfadizine (SDZ), in cow urine wastewater. Biodegradation pathways were proposed on the basis of key metabolites identified using high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (HPLC-QqTOF-MS). Transcriptomic, metabolomic, and free radical analyses were performed to explore the functional groups and detailed molecular mechanisms of SDM and SDZ degradation. A total of 27 UniGene clusters showed significant differences between luffa fiber and luffa fiber-free systems, which were significantly correlated to cellulose catabolism, carbohydrate metabolism, and oxidoreductase activity. Carbohydrate-active enzymes and oxidoreductases appear to play particularly important roles in SDM and SDZ degradation. Electron paramagnetic resonance (EPR) spectroscopy revealed the generation and evolution of OH and R during the biodegradation of SDM and SDZ, suggesting that beyond enzymatic degradation, SDM and SDZ were also transformed through a free radical pathway. Luffa fiber also acts as a co-substrate to improve the activity of enzymes for the degradation of SDM and SDZ. This research provides a potential strategy for removing SDM and SDZ from agricultural and industrial wastewater using fungal-luffa fiber systems.

Trainee surgeons and patient outcomes in carotid endarterectomy: a retrospective cohort study

BACKGROUND

In Australia and New Zealand, more than 2000 carotid endarterectomies are performed annually. The major morbidities arising from this procedure are post-operative stroke, cranial nerve injury and death. Carotid endarterectomy surgery is a key component of the vascular surgical training programme. We assessed the impact of having a surgical trainee perform a major component of this procedure on the post-operative rates of stroke, cranial nerve injury and mortality.

METHODS

We performed a retrospective cohort study of vascular surgical patients undergoing carotid endarterectomy, with data obtained from the Australasian Vascular Audit database between January 2010 and December 2014. The dataset comprised of 6528 carotid endarterectomies performed during this time. The collected data were stratified into two categories - consultant-led cases, and those in which trainee surgeons performed at least a major component of the surgery under consultant supervision. The results were analysed for differences in post-operative stroke, cranial nerve injury and inpatient mortality. Differences between groups were assessed using multivariate analysis, adjusting for potentially confounding covariables.

RESULTS

On multivariate analysis, there was no statistically significant difference in the rates of post-operative stroke (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.57-1.36, P = 0.55), cranial nerve injury (OR 0.68, 95% CI 0.39-1.21, P = 0.19) or inpatient mortality (OR 0.78, 95% CI 0.29-2.13, P = 0.63) between the two cohorts.

CONCLUSION

Having surgical trainees perform components of carotid endarterectomies under supervision is not associated with an increased rate of post-operative stroke, cranial nerve injury or mortality.

Monitoring, assessment, and prediction of microbial shifts in coupled catalysis and biodegradation of 1,4-dioxane and co-contaminants

Microbial community dynamics were characterized following combined catalysis and biodegradation treatment trains for mixtures of 1,4-dioxane and chlorinated volatile organic compounds (CVOCs) in laboratory microcosms. Although a few specific bacterial taxa are capable of removing 1,4-dioxane and individual CVOCs, many microorganisms are inhibited when these contaminants are present in mixtures. Chemical catalysis by tungstated zirconia (WO_x/ZrO₂) and hydrogen peroxide (H₂O₂) as a non-selective treatment was designed to achieve nearly 20% 1,4-dioxane and over 60% trichloroethene and 50% dichloroethene removals. Post-catalysis, bioaugmentation with 1,4-dioxane metabolizing bacterial strain,Pseudonocardia dioxanivorans CB1190, removed the remaining 1,4-dioxane. The evolution of the microbial community under different conditions was time-dependent but relatively independent of the concentrations of contaminants. The compositions of microbiomes tended to be similar regardless of complex contaminant mixtures during the biodegradation phase, indicating a r-K strategy transition attributed to the shock experienced during catalysis and the subsequent incubation. The originally dominant genera Pseudomonas and Ralstonia were sensitive to catalytic oxidation, and were overwhelmed by Sphingomonas, Rhodococcus, and other catalyst-tolerant microbes, but microbes capable of biodegradation of organics thrived during the incubation. Methane metabolism, chloroalkane-, and chloroalkene degradation pathways appeared to be responsible for CVOC degradation, based on the identifications of haloacetate dehalogenases, 2-haloacid dehalogenases, and cytochrome P450 family. Network analysis highlighted the potential interspecies competition or commensalism, and dynamics of microbiomes during the biodegradation phase that were in line with shifting predominant genera, confirming the deterministic processes guiding the microbial assembly. Collectively, this study demonstrated that catalysis followed by bioaugmentation is an effective treatment for 1,4-dioxane in the presence of high CVOC concentrations, and it enhanced our understanding of microbial ecological impacts resulting from abiotic-biological treatment trains. These results will be valuable for predicting treatment synergies that lead to cost savings and improve remedial outcomes in short-term active remediation as well as long-term changes to the environmental microbial communities.

Cometabolic biotransformation of 1,4-dioxane in mixtures with hexavalent chromium using attached and planktonic bacteria

Biological treatment of 1,4-dioxane, a probable human carcinogen and a recalcitrant contaminant of concern, is often complicated by the presence of inhibitory co-contaminants. Due to its use as a solvent, wetting agent, and stabilizer for chlorinated solvents employed in metal vapor degreasing, 1,4-dioxane has often been found to occur with a variety of co-contaminants, including heavy metals such as hexavalent chromium [Cr(VI)]. Cr(VI) also occurs naturally in groundwater due to geological formations, but also has sources that can coincide with 1,4-dioxane from anthropogenic activities such as metal vapor degreasing. Biodegradation of 1,4-dioxane can be accomplished by microbes that use it as a source of carbon or energy as well as those that cometabolize it after growth on other organic substrates. A propanotroph, Mycobacterium austroafricanum JOB5, was grown in planktonic pure cultures and biofilms to determine its ability to cometabolize 1,4-dioxane in the presence of varying concentrations of Cr(VI). 1,4-Dioxane cometabolism by JOB5 planktonic cells was uninhibited by Cr(VI) at levels up to 10 mg/L, while biofilms were only mildly inhibited at 10 mg/L. As an important part of the biofilms commonly found in subsurface aquifers and engineered systems, extracellular polymeric substances (EPS) were found to play an important role in preventing Cr(VI) exposure to cells. We observed that soluble EPS were able to bind to Cr(VI) and theorize that biofilm-associated EPS additionally served to impede penetration of the biofilm structure by Cr(VI), thus mitigating exposure and toxicity. These findings suggest that bioremediation would be a viable treatment strategy for 1,4-dioxane-contaminated waters that contain elevated levels of Cr(VI) in natural and built environments.

Mechanisms of 1,4-Dioxane Biodegradation and Adsorption by Bio-Zeolite in the Presence of Chlorinated Solvents: Experimental and Molecular Dynamics Simulation Studies

The use of bioaugmented zeolite (bio-zeolite) can be an effective technology for irreversibly removing recalcitrant organic pollutants in aqueous mixtures. Removal of 1,4-dioxane by a bio-zeolite (Pseudonocardia dioxanivorans CB1190-bioaugmented ZSM-5) in the presence of several chlorinated volatile organic compounds (CVOCs) was superior to removal by adsorption using abiotic zeolite. Mixtures containing 1,1-dichloroethene (1,1-DCE) were an exception, which completely inhibited the bio-zeolite system. Specific adsorption characteristics were studied using adsorption isotherms in single-solute and bisolute systems accompanied by Polanyi theory-based Dubinin-Astakhov (DA) modeling. Adsorption behavior was examined using characteristic energy (E_a/H) from modified DA models and molecular dynamics simulations. While the tight-fit of 1,4-dioxane in the hydrophobic channels of ZSM-5 appears to drive 1,4-dioxane adsorption, the greater hydrophobicity of trichloroethene and cis-1,2-dichloroethene cause them have a greater affinity over 1,4-dioxane for adsorption sites on the zeolite. 1,4-Dioxane was desorbed and displaced by CVOCs except 1,1-DCE because of its low E_a/H value, explaining why bio-zeolite only biodegraded 1,4-dioxane in 1,1-DCE-free CVOC mixtures. Understanding the adsorption mechanisms of solutes in complex mixtures is crucial for the implementation of sorption-based treatment technologies for the removal of complex contaminant mixtures from aquatic environments.

Indicators of Risk for Dental Caries in Children: A Holistic Approach

BACKGROUND

Dental caries in children is a major public health problem worldwide, with a multitude of determinants acting upon children to different degrees in different communities. The objective of this study was to determine maternal, environmental, and intraoral indicators of dental caries experience in a sample of 6- to 7-y-old children in South East Queensland, Australia.

METHODS

A total of 174 mother-child dyads were recruited for this cross-sectional study from the Griffith University Environments for Healthy Living birth cohort study. Maternal education, employment status, and prepregnancy body mass index were maternal indicators, and annual household income was taken as a proxy for environmental indicators. These were collected as baseline data of the study. Clinical data on children's dental caries experience, saliva characteristics of buffering capacity, stimulated flow rate, and colony-forming units per milliliter of salivary mutans streptococci were collected for the oral health substudy. Univariate analysis was performed with 1-way analysis of variance and chi-square tests. Caries experience was the outcome, which was classified into 4 categories based on the number of carious tooth surfaces. Ordinal logistic regression was used to explore the association of risk indicators with caries experience.

RESULTS

Age (P = 0.021), low salivary buffering capacity (P = 0.001), reduced levels of salivary flow rate (P = 0.011), past caries experience (P = 0.001), low annual household income; <$30,000 (P = 0.050) and <$60,000 (P = 0.033) and maternal employment status (P = 0.043) were associated with high levels of dental caries.

CONCLUSION

These data support the evidence of associations between maternal, environmental, and children's intraoral characteristics and caries experience among children in a typical Western industrialized country. All of these need to be considered in preventative strategies within families and communities.

KNOWLEDGE TRANSFER STATEMENT

The results of this study can be used by clinicians, epidemiologists, and policy makers to identify children who are at risk of developing dental caries. With consideration of costs for treatment for the disease, this information could be used to plan cost-effective and patient-centered preventive care.

Response and recovery of microbial communities subjected to oxidative and biological treatments of 1,4-dioxane and co-contaminants

Microbial community dynamics were characterized following combined oxidation and biodegradation treatment trains for mixtures of 1,4-dioxane and chlorinated volatile organic compounds (CVOCs) in laboratory microcosms. Bioremediation is generally inhibited by co-contaminate CVOCs; with only a few specific bacterial taxa reported to metabolize or cometabolize 1,4-dioxane being unaffected. Chemical oxidation by hydrogen peroxide (H₂O₂) as a non-selective treatment demonstrated 50-80% 1,4-dioxane removal regardless of the initial CVOC concentrations. Post-oxidation bioaugmentation with 1,4-dioxane metabolizer Pseudonocardia dioxanivorans CB1190 removed the remaining 1,4-dioxane. The intrinsic microbial population, biodiversity, richness, and biomarker gene abundances decreased immediately after the brief oxidation phase, but recovery of cultivable microbiomes and a more diverse community were observed during the subsequent 9-week biodegradation phase. Results generated from the Illumina Miseq sequencing and bioinformatics analyses established that generally oxidative stress tolerant genus Ralstonia was abundant after the oxidation step, and Cupriavidus, Pseudolabrys, Afipia, and Sphingomonas were identified as dominant genera after aerobic incubation. Multidimensional analysis elucidated the separation of microbial populations as a function of time under all conditions, suggesting that temporal succession is a determining factor that is independent of 1,4-dioxane and CVOCs mixtures. Network analysis highlighted the potential interspecies competition or commensalism, and dynamics of microbiomes during the biodegradation phase, in line with the shifts of predominant genera and various developing directions during different steps of the treatment train. Collectively, this study demonstrated that chemical oxidation followed by bioaugmentation is effective for treating 1,4-dioxane, even in the presence of high levels of CVOC mixtures and residual peroxide, a disinfectant, and enhanced our understanding of microbial ecological impacts of the treatment train. These results will be valuable for predicting treatment synergies that lead to cost savings and improved remedial outcomes in short-term active remediation as well as long-term changes to the environmental microbial communities.

Salivary characteristics and dental caries experience in remote Indigenous children in Australia: a cross-sectional study

Background

While associations between salivary characteristics and dental caries have been well studied, we are not aware of this being assessed in a remote Indigenous child population, where lifestyles may be different from urban children. Our aim was to assess associations between caries experience and putative biomarkers in saliva, accounting for oral hygiene and dietary habits.

Methods

Children attending schools in an Indigenous community in remote north Queensland, Australia were invited to an oral examination by qualified and calibrated examiners. Salivary flow rate, pH, buffering capacity and loads of mutans streptococci (MS), lactobacilli (LB) and yeasts were determined. Also, data on tooth brushing frequency and soft drinks consumption were obtained via a questionnaire. Caries experience was recorded by the International Caries Detection and Assessment System (ICDAS-II), and quantified as decayed, missing and filled surfaces. Relationships between the salivary variables and the cumulative caries experience (dmfs+DMFS) in the deciduous and permanent dentitions were examined by multivariate analyses to control the effect of confounders.

Results

The mean cumulative decayed (DS + ds), missing (MS + ms) and filled (FS + fs) surfaces were 3.64 (SD: 4.97), 1.08 (4.38) and 0.79 (1.84) respectively. Higher salivary MS and LB counts, low tooth brushing frequency and daily soft drink consumption were significantly related to greater caries experience. Caries experience was about twice in those with ≥10^5 CFU/ml saliva counts of MS (mean = 6.33, SD: 8.40 vs 3.11, 5.77) and LB (7.03, 7.49 vs 4.41, 8.00). In the fully-adjusted multivariate model, caries experience in those with higher counts of MS and LB were 51 and 52% more than those with lower counts.

Conclusions

As with studies in other populations, childhood salivary counts of MS and LB were significantly associated with greater caries experience in this remote Indigenous community. To address the serious burden of oral disease, we are researching ways to promote a healthy oral environment by encouraging good dietary habits, and emphasising the importance of daily tooth brushing with a fluoridated toothpaste. Our ongoing longitudinal studies will indicate the success of measures employed to reduce the counts of bacteria closely associated with cariogenesis and their impact on caries increment.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR), No: ACTRN12615000693527; date of registration: 3rd July 2015.

Risk factors for oral health in young, urban, Aboriginal and Torres Strait Islander children

Background

The caries process follows a strong social gradient which can commence in the first years of life. Yet data on young children remain limited. This study reports the potential risk factors and indicators in urban, Aboriginal and Torres Strait Islander children aged less than 5 and estimates the prevalence of caries.

Methods

Demographic and risk factor and risk indicator data were collected at baseline in a cohort study of children attending a health clinic in north Brisbane. Dentulous children received a basic oral examination to explore the presence of decayed, missing and filled teeth (dmft). Descriptive analyses were performed. A backwards stepwise logistic regression model was performed to identify potential associations with dmft status.

Results

In this study, 180 children enrolled: 111 children received the oral examination, of whom 14 (12.6%) (mean age 35 months) were estimated to have dmft >0. There was a high prevalence of socio‐economic, dietary and behavioural risk factors/indicators present for children. Due to the small sample size, planned regression was not performed.

Conclusions

Overall, the prevalence of risk factors and risk indicators for caries in the study population is high. More culturally appropriate resources that support preventive care need to be invested before children are school aged.

Co-contaminant effects on 1,4-dioxane biodegradation in packed soil column flow-through systems

Biodegradation of 1,4-dioxane was examined in packed quartz and soil column flow-through systems. The inhibitory effects of co-contaminants, specifically trichloroethene (TCE), 1,1-dichloroethene (1,1-DCE), and copper (Cu²⁺) ions, were investigated in the columns either with or without bioaugmentation with a 1,4-dioxane degrading bacterium Pseudonocardia dioxanivorans CB1190. Results indicate that CB1190 cells readily grew and colonized in the columns, leading to significant degradation of 1,4-dioxane under oxic conditions. Degradation of 1,4-dioxane was also observed in the native soil (without bioaugmentation), which had been previously subjected to enhanced reductive dechlorination treatment for co-contaminants TCE and 1,1-DCE. Bioaugmentation of the soil with CB1190 resulted in nearly complete degradation at influent concentrations of 3-10 mg L^-1 1,4-dioxane and a residence reaction time of 40-80 h, but the presence of co-contaminants, 1,1-DCE and Cu²⁺ ions (up to 10 mg L^-1), partially inhibited 1,4-dioxane degradation in the untreated and bioaugmented soil columns. However, the inhibitory effects were much less severe in the column flow-through systems than those previously observed in planktonic cultures, which showed near complete inhibition at the same co-contaminant concentrations. These observations demonstrate a low susceptibility of soil microbes to the toxicity of 1,1-DCE and Cu²⁺ in packed soil flow-through systems, and thus have important implications for predicting biodegradation potential and developing sustainable, cost-effective technologies for in situ remediation of 1,4-dioxane contaminated soils and groundwater.

High Prevalence of Lifestyle Factors Attributable for Oral Cancer, and of Oral Potentially Malignant Disorders in Rural Sri Lanka

Background:

Oral Cancer is a major public health problem in most of the South East Asian countries including Sri Lanka. Use of tobacco in the form of smokeless tobacco and smoking, use of alcohol and betel quid chewing are the major contributory factors for causation oral cancer. The aim of this study was to investigate the prevalence of lifestyle factors responsible for causation of oral cancer and Oral Potentially Malignant Disorders (OPMD) in the Sabaragamuwa province of Sri Lanka.

Methods:

A cross-sectional community based study was conducted in Sabaragamuwa province by interviewing, then conducting an oral examination, on 1029 subjects over 30 years of age, over a one year period from November 2006. The study protocol included an interviewer-administered questionnaire to gather socio-demographic factors, recording of habits that included areca/betel chewing, smoking, and alcohol consumption. A three-day food diary was obtained, particularly to assess the consumption of tea, fruits and vegetables. The weight and height of residents was taken for calculation of Body Mass Index (BMI).

Results:

One hundred and two individuals with one or more OPMD were detected among these 1029 subjects. The prevalence of OPMD, weighted according to the estate sector and gender, was estimated as 11.3%. The prevalence of daily betel quid chewing in this study was 53.8%: 15.7% without tobacco and 47.4% with tobacco. The prevalence of individuals who reported consumption of alcohol at least weekly was 13.4%. A significant minority, 31.7%, were under nourished, with a BMI < 18.5. Forty six percent of the males practiced combined habits of betel quid chewing, smoking and regular use of alcohol.

Conclusions:

This study discloses high prevalence of OPMD and of lifestyle factors for oral cancer in these communities. There is an urgent need for a comprehensive strategy to control the use of tobacco, betel quid chewing and alcohol for prevention of oral cancer.

Abiotic and bioaugmented granular activated carbon for the treatment of 1,4-dioxane-contaminated water

1,4-Dioxane is a probable human carcinogen and an emerging contaminant that has been detected in surface water and groundwater resources. Many conventional water treatment technologies are not effective for the removal of 1,4-dioxane due to its high water solubility and chemical stability. Biological degradation is a potentially low-cost, energy-efficient approach to treat 1,4-dioxane-contaminated waters. Two bacterial strains, Pseudonocardia dioxanivorans CB1190 (CB1190) and Mycobacterium austroafricanum JOB5 (JOB5), have been previously demonstrated to break down 1,4-dioxane through metabolic and co-metabolic pathways, respectively. However, both CB1190 and JOB5 have been primarily studied in laboratory planktonic cultures, while most environmental microbes grow in biofilms on surfaces. Another treatment technology, adsorption, has not historically been considered an effective means of removing 1,4-dioxane due to the contaminant's low K_oc and K_ow values. We report that the granular activated carbon (GAC), Norit 1240, is an adsorbent with high affinity for 1,4-dioxane as well as physical dimensions conducive to attached bacterial growth. In abiotic batch reactor studies, 1,4-dioxane adsorption was reversible to a large extent. By bioaugmenting GAC with 1,4-dioxane-degrading microbes, the adsorption reversibility was minimized while achieving greater 1,4-dioxane removal when compared with abiotic GAC (95-98% reduction of initial 1,4-dioxane as compared to an 85-89% reduction of initial 1,4-dioxane, respectively). Bacterial attachment and viability was visualized using fluorescence microscopy and confirmed by amplification of taxonomic genes by quantitative polymerase chain reaction (qPCR) and an ATP assay. Filtered samples of industrial wastewater and contaminated groundwater were also tested in the bioaugmented GAC reactors. Both CB1190 and JOB5 demonstrated 1,4-dioxane removal greater than that of the abiotic adsorbent controls. This study suggests that bioaugmented adsorbents could be an effective technology for 1,4-dioxane removal from contaminated water resources.

Inflammatory Bacteriome and Oral Squamous Cell Carcinoma

Results from microbiome studies on oral cancer have been inconsistent, probably because they focused on compositional analysis, which does not account for functional redundancy among oral bacteria. Based on functional prediction, a recent study revealed enrichment of inflammatory bacterial attributes in oral squamous cell carcinoma (OSCC). Given the high relevance of this finding to carcinogenesis, we aimed here to corroborate them in a case-control study involving 25 OSCC cases and 27 fibroepithelial polyp (FEP) controls from Sri Lanka. DNA extracted from fresh biopsies was sequenced for the V1 to V3 region with Illumina's 2 × 300-bp chemistry. High-quality nonchimeric merged reads were classified to the species level with a prioritized BLASTN-based algorithm. Downstream compositional analysis was performed with QIIME (Quantitative Insights into Microbial Ecology) and linear discriminant analysis effect size, while PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was utilized for bacteriome functional prediction. The OSCC tissues tended to have lower species richness and diversity. Genera Capnocytophaga, Pseudomonas, and Atopobium were overrepresented in OSCC, while Lautropia, Staphylococcus, and Propionibacterium were the most abundant in FEP. At the species level, Campylobacter concisus, Prevotella salivae, Prevotella loeschii, and Fusobacterium oral taxon 204 were enriched in OSCC, while Streptococcus mitis, Streptococcus oral taxon 070, Lautropia mirabilis, and Rothia dentocariosa among others were more abundant in FEP. Functionally, proinflammatory bacterial attributes, including lipopolysaccharide biosynthesis and peptidases, were enriched in the OSCC tissues. Thus, while the results in terms of species composition significantly differed from the original study, they were consistent at the functional level, substantiating evidence for the inflammatory nature of the bacteriome associated with OSCC.

Dopamine acting at D1-like, D2-like and α1-adrenergic receptors differentially modulates theta and gamma oscillatory activity in primary motor cortex

The loss of dopamine (DA) in Parkinson’s is accompanied by the emergence of exaggerated theta and beta frequency neuronal oscillatory activity in the primary motor cortex (M1) and basal ganglia. DA replacement therapy or deep brain stimulation reduces the power of these oscillations and this is coincident with an improvement in motor performance implying a causal relationship. Here we provide in vitro evidence for the differential modulation of theta and gamma activity in M1 by DA acting at receptors exhibiting conventional and non-conventional DA pharmacology. Recording local field potentials in deep layer V of rat M1, co-application of carbachol (CCh, 5 μM) and kainic acid (KA, 150 nM) elicited simultaneous oscillations at a frequency of 6.49 ± 0.18 Hz (theta, n = 84) and 34.97 ± 0.39 Hz (gamma, n = 84). Bath application of DA resulted in a decrease in gamma power with no change in theta power. However, application of either the D1-like receptor agonist SKF38393 or the D2-like agonist quinpirole increased the power of both theta and gamma suggesting that the DA-mediated inhibition of oscillatory power is by action at other sites other than classical DA receptors. Application of amphetamine, which promotes endogenous amine neurotransmitter release, or the adrenergic α1-selective agonist phenylephrine mimicked the action of DA and reduced gamma power, a result unaffected by prior co-application of D1 and D2 receptor antagonists SCH23390 and sulpiride. Finally, application of the α1-adrenergic receptor antagonist prazosin blocked the action of DA on gamma power suggestive of interaction between α1 and DA receptors. These results show that DA mediates complex actions acting at dopamine D1-like and D2-like receptors, α1 adrenergic receptors and possibly DA/α1 heteromultimeric receptors to differentially modulate theta and gamma activity in M1.

Phase-amplitude coupled persistent theta and gamma oscillations in rat primary motor cortex in vitro

In vivo, theta (4-7 Hz) and gamma (30-80 Hz) neuronal network oscillations are known to coexist and display phase-amplitude coupling (PAC). However, in vitro, these oscillations have for many years been studied in isolation. Using an improved brain slice preparation technique we have, using co-application of carbachol (10 μM) and kainic acid (150 nM), elicited simultaneous theta (6.6 ± 0.1 Hz) and gamma (36.6 ± 0.4 Hz) oscillations in rodent primary motor cortex (M1). Each oscillation showed greatest power in layer V. Using a variety of time series analyses we detected significant cross-frequency coupling in 74% of slice preparations. Differences were observed in the pharmacological profile of each oscillation. Thus, gamma oscillations were reduced by the GABA_A receptor antagonists, gabazine (250 nM and 2 μM), and picrotoxin (50 μM) and augmented by AMPA receptor antagonism with SYM2206 (20 μM). In contrast, theta oscillatory power was increased by gabazine, picrotoxin and SYM2206. GABA_B receptor blockade with CGP55845 (5 μM) increased both theta and gamma power, and similar effects were seen with diazepam, zolpidem, MK801 and a series of metabotropic glutamate receptor antagonists. Oscillatory activity at both frequencies was reduced by the gap junction blocker carbenoxolone (200 μM) and by atropine (5 μM). These data show theta and gamma oscillations in layer V of rat M1 in vitro are cross-frequency coupled, and are mechanistically distinct. The development of an in vitro model of phase-amplitude coupled oscillations will facilitate further mechanistic investigation of the generation and modulation of coupled activity in mammalian cortex.

Evaluation of the utilization of primary healthcare staff for control of oral cancer

Background:

Population-based screening programmes utilizing primary healthcare (PHC) staff have been undertaken in several countries with high incidence of oral cancer and oral potentially malignant disorders (OPMDs).

Objective:

The main objective of this study is to re-evaluate the utilization of PHC staff for the detection of OPMD and the early detection of oral cancer.

Methods:

A cross-sectional community-based study was done in the Sabaragamuwa province in Sri Lanka by conducting interview and oral examination on 1029 subjects aged 30 years or more, over a 1 year period from November 2006. The study protocol included an interviewer-administered questionnaire to gather sociodemographic factors and lifestyle habits. A 2-day training programme involving didactic sessions followed by practical field training was held for all local PHC staff ( n = 67). Subjects screened by PHC staff were re-examined by the principal investigator (PI) to assess the validity of the screening.

Results:

A total of 685 subjects were screened by both PHC staff and the PI. In terms of the detection of any abnormality, sensitivity of the screening by PHC workers was 63%, with a specificity of 82.6%, a positive predictive value (PPV) of 24.8% and negative predictive value of 96.1%. Of the various OPMDs, poor agreement was noted in the detection of early oral submucous fibrosis. Among intra-oral sites missed by PHC staff, surprisingly high numbers were in the buccal mucosa and commissures.

Conclusion:

Low sensitivity and PPV in the present study indicate the necessity for improved training and facilities for better visualization of all intra-oral sites and/or an entirely different approach. An alternative strategy based on determining risk factors in the lives of individuals, with referral to local government dental clinics, could be a better option for screening for early detection of oral cancer in the South Asian scenario.

Comorbidities associated with HIV and antiretroviral therapy (clinical sciences): a workshop report

In the era of combination antiretroviral therapy (ART), parsing out the effects of HIV vs ART on health outcomes is challenging. Nadir CD4 count, a marker of the extent of immunosuppression, has significant long-term impact on an array of disease states in HIV+ persons; however, in the dental literature, reporting of pre-ART exposure to immunosuppression has largely been ignored and this limits the validity of previous studies. In Workshop A1, we explain fully the importance of nadir CD4, pre-ART immunosuppression, and identify a need to include specific variables in future research. The questions posed herein are challenging, typically not neatly addressed by any one study and require integration of the latest evidence from the wider medical literature. We consider topics beyond the confines of the oral cavity and examine oral health in the complex context of ART era HIV immunopathophysiology. We depict how variability in geographic setting and time period (pre- and post-ART era) can impact oral conditions - influencing when HIV infection was detected (at what CD4 count), the type and timing of ART as well as social determinants such as strong stigma and limited access to care. We hope our Workshop will stir debate and energize a rigorous focus on relevant areas of future research in HIV/AIDS.

Effectiveness of water fluoridation in caries reduction in a remote Indigenous community in Far North Queensland

BACKGROUND

Children in remote Indigenous communities in Australia have levels of dental caries much greater than the national average. One such, the Northern Peninsula Area of Far North Queensland (NPA), had an oral health survey conducted in 2004, shortly before the introduction of fluoridated, reticular water. Children were again surveyed in 2012, following five years exposure.

METHODS

An oral examination was conducted on all consenting children enrolled in schools across the community, using WHO Basic Oral Health Survey methodology.

RESULTS

Few teeth had restorations in both surveys. Age-weighted overall caries prevalence and severity declined from 2005 to 2012 by 37.3%. The effect was most marked in younger children, dmft decreasing by approximately 50% for ages 4-9 years; at age 6, mean decayed score decreased from 5.20 to 3.43. DMFT levels also decreased by almost half in 6-9 year olds. However, significant unmet treatment needs exist at all ages.

CONCLUSIONS

There has been considerable improvement in child dental health in the NPA over the past 6-7 years. In light of continued poor diet and oral hygiene, water fluoridation is the most likely explanation. The cost-effectiveness for this small community remains an issue which, in the current climate of political antagonism to water fluoridation in many quarters, requires continued study.

Successful treatment of iatrogenic multicentric Castleman's disease arising due to recrudescence of HHV-8 in a liver transplant patient

We describe the case of a 59-year-old HIV-negative male who developed multicentric Castleman's disease (MCD) 1 year postliver transplantation due to recrudescence of a pretransplant human herpesvirus-8 (HHV-8) infection. He presented with fevers, dry cough, weight loss and drenching night sweats. Routine investigations were all unremarkable. Computerized axial tomography (CT) scans showed splenomegaly and intra-abdominal lymphadenopathy, confirmed by positron emission tomography. Cervical lymph node biopsies were consistent with MCD. The presence of HHV-8 was confirmed on immunohistochemistry. Peripheral blood HHV-8 quantitative polymerase chain reaction (qPCR) monitoring showed a threefold decrease in viremia in the first week of treatment with ganciclovir but had little impact on clinical symptoms. Reducing immunosuppression and switching to rituximab resolved clinical symptoms and produced a negative HHV-8 qPCR result. Retrospective molecular testing of sera collected pre- and immediately posttransplantation confirmed preexisting HHV-8 in the host. This is the first reported case of an HIV-negative postliver transplant patient developing MCD that manifested as posttransplant lymphoproliferative disorder due to recrudescence of HHV-8. We propose (1) the introduction of the term iatrogenic Castleman's disease (CD) for this and similar cases, (2) rituximab should be considered as a treatment option for CD and (3) consideration be given to a change to the World Health Organization classification of CD to incorporate such cases.

Comparison of salivary collection and processing methods for quantitative HHV-8 detection

OBJECTIVES

Saliva is a proved diagnostic fluid for the qualitative detection of infectious agents, but the accuracy of viral load determinations is unknown. Stabilising fluids impede nucleic acid degradation, compared with collection onto ice and then freezing, and we have shown that the DNA Genotek P-021 prototype kit (P-021) can produce high-quality DNA after 14 months of storage at room temperature. Here we evaluate the quantitative capability of 10 collection/processing methods.

METHODS

Unstimulated whole mouth fluid was spiked with a mixture of HHV-8 cloned constructs, 10-fold serial dilutions were produced, and samples were extracted and then examined with quantitative PCR (qPCR). Calibration curves were compared by linear regression and qPCR dynamics.

RESULTS

All methods extracted with commercial spin columns produced linear calibration curves with large dynamic range and gave accurate viral loads. Ethanol precipitation of the P-021 does not produce a linear standard curve, and virus is lost in the cell pellet. DNA extractions from the P-021 using commercial spin columns produced linear standard curves with wide dynamic range and excellent limit of detection.

CONCLUSION

When extracted with spin columns, the P-021 enables accurate viral loads down to 23 copies μl(-1) DNA. The quantitative and long-term storage capability of this system makes it ideal for study of salivary DNA viruses in resource-poor settings.

Preschool teachers as agents of oral health promotion: an intervention study in Sri Lanka

BACKGROUND

According to National Oral Health Survey reports and research, Early Childhood Caries has been identified as a serious public health problem in Sri Lanka. More than 65% of preschool-aged children have dental decay and only 2% of them have had treatment. With proper interventions and commitment from public health personnel and responsible community leaders this should be a largely preventable disease.

METHODS

An intervention study was conducted among preschool teachers in the District of Colombo, Sri Lanka, to assess their influence on oral health promotion in the school environment. All the available 52 preschools and all 72 teachers registered under a local government authority were involved in the study. Preschools were divided into intervention group and control group based on geographically defined areas. The intervention included training preschool teachers using a manual covering health education, health promotion, incorporation of oral-health-friendly activities into the preschool curriculum, and hands-on experience of oral examination. Pre- and post- assessments were conducted with a 6 month interval.

RESULTS

After 6 months, the median oral health knowledge score of the intervention group improved from 55 to 72 (p = 0.005) and the mean score for oral health related practices from 32 to 35 (p = 0.032). The variables: oral-health-friendly preschool environment (p = 0.02), availability of brushing facilities (p = 0.005) and availability of information, education and communication materials related to oral health (p = 0.004) were significantly different between the two groups after 6 months.

CONCLUSION

Oral health promotion activities can be effectively instilled in a pre-school environment by the education of teachers.

Constant light disrupts the circadian rhythm of steroidogenic proteins in the rat adrenal gland

The circadian rhythm of corticosterone (CORT) secretion from the adrenal cortex is regulated by the suprachiasmatic nucleus (SCN), which is entrained to the light-dark cycle. Since the circadian CORT rhythm is associated with circadian expression of the steroidogenic acute regulatory (StAR) protein, we investigated the 24h pattern of hormonal secretion (ACTH and CORT), steroidogenic gene expression (StAR, SF-1, DAX1 and Nurr77) and the expression of genes involved in ACTH signalling (MC2R and MRAP) in rats entrained to a normal light-dark cycle. We found that circadian changes in ACTH and CORT were associated with the circadian expression of all gene targets; with SF-1, Nurr77 and MRAP peaking in the evening, and DAX1 and MC2R peaking in the morning. Since disruption of normal SCN activity by exposure to constant light abolishes the circadian rhythm of CORT in the rat, we also investigated whether the AM-PM variation of our target genes was also disrupted in rats exposed to constant light conditions for 5weeks. We found that the disruption of the AM-PM variation of ACTH and CORT secretion in rats exposed to constant light was accompanied by a loss of AM-PM variation in StAR, SF-1 and DAX1, and a reversed AM-PM variation in Nurr77, MC2R and MRAP. Our data suggest that circadian expression of StAR is regulated by the circadian expression of nuclear receptors and proteins involved in both ACTH signalling and StAR transcription. We propose that ACTH regulates the secretion of CORT via the circadian control of steroidogenic gene pathways that become dysregulated under the influence of constant light.

Trends and ethnic disparities in oral and oro-pharyngeal cancers in South Africa, 1992-2001

OBJECTIVE

To describe trends in the epidemiology of oral and of oro-pharyngeal (OAP) cancers in South Africa for the atest period available.

METHODS

Data were obtained from the South African pathology-based National Cancer Registry. All new cases of OAP cancers diagnosed and confirmed histologically from 1992 to 2001 are included for the ICD-10 sites C00 to C14, excluding those involving the major salivary glands (C07-C08) and the nasopharynx (C11). OAP cancer incidence is reported by demographics (gender, age, race/ethnicity) and the anatomical sites involved. The analysis on anatomical sites was restricted to squamous cell carcinomas.

RESULTS

Overall, males had a much higher OAP cancer incidence rate (world age-Standardised incidence rate [ASIR] = 7.01/100 000 per year) than females (ASIR = 1.99). However, among Asian/Indian South Africans, OAP cancer incidence was higher among females (ASIR = 4.60) than among males (ASIR = 3.80). OAP cancer, excluding those involving the lip, was highest among Coloureds (ASIR = 5.72) and lowest among Blacks (ASIR = 3.16). OAP cancer incidence was stable overall, but incidence rates increased significantly among Coloured South Africans over the period under review (p < 0.05). Cancer specifically involving the oro-pharyngeal was most common among Coloureds and showed an increasing trend during the period under review.

CONCLUSIONS

Variations in the incidence of OAP cancers by gender, race/ethnicity and anatomic site indicate a need for culturally-targeted reductions in major risk factors, including promoting tobacco cessation and prevention of risky alcohol use. The implications of the role of the human papillomavirus (HPV) in the prevention of squamous cell carcinomas involving the oro-pharyngeal in South Africa require further investigation.

Interprofessional learning enhances knowledge of roles but is less able to shift attitudes: a case study from dental education

INTRODUCTION

Interprofessional education (IPE) purports to improve team working through improved knowledge of the roles of others, and by engendering mutual respect. This case study aimed to determine the impact of an IPE curriculum on knowledge and attitudes of dentistry and dental technology students undertaking these curricula in the new School of Dentistry and Oral Health at Griffith University. All dental technology students and third- and final- (fifth) year dentistry students were invited to participate.

METHOD

A mixed-method approach was used to compare attitudes, perceptions and experiences of students involved in our IPE curricula. Quantitative data were evaluated with the Statistical Package for the Social Sciences (SPSS), and qualitative findings were explored through an Excel(®) spreadsheet coding frame tested against Leximancer™ qualitative software for consistency.

RESULTS

Forty-six of the 131 eligible students participated. Readiness for Interprofessional Learning Scales (RIPLS) and focus groups consistently showed that IPE positively influenced professional identity and improved communication between and amongst all students and assisted them in developing their roles. A prevailing sense of greater importance and a lack of mutual respect between dentistry and dental technology students were, unfortunately, evident. The process was, however, sufficient to enhance teamwork and collaboration when planned learning revolved around explicit patient care in the provision of dental prostheses.

CONCLUSION

Further development of such curricula is needed to maximise IP learning (IPL) opportunities, to shift traditional attitudes and, potentially, to improve the outcomes of patient care. To enable this, academic and clinical leaders need to embrace the ideals of IPE.

When can oral health education begin? Relative effectiveness of three oral health education strategies starting pre-partum

OBJECTIVE

To test the impact of oral health education provided to pregnant mothers on subsequent practices within the infant's family.

RESEARCH DESIGN

A quasi-experimental intervention trial comparing the effectiveness of 'usual care' to one, or both, of two oral health education resources: a 'sample bag' of information and oral health care products; and/or a nine-minute "Healthy Teeth for Life" video on postnatal oral health issues.

PARTICIPANTS

Women attending the midwife clinic at approximately 30 weeks gestation were recruited (n=611) in a public hospital providing free maternity services.

RESULTS AND CONCLUSIONS

Four months after the birth of their infant, relative to the usual care condition, each of the oral health education interventions had independent or combined positive impacts on mother's knowledge of oral health practices. However young, single, health care card-holder or unemployed mothers were less likely to apply healthy behaviours or to improve knowledge of healthy choices, as a result of these interventions. The video intervention provided the strongest and most consistent positive impact on mothers' general and infant oral health knowledge. While mothers indicated that the later stage of pregnancy was a good time to receive oral health education, many suggested that this should also be provided after birth at a time when teeth were a priority issue, such as when "baby teeth" start to erupt.

The electronic structure of lithium metagallate

Herein we present a study of the electronic structure of lithium metagallate (LiGaO(2)), a material of interest in the field of optoelectronics. We use soft x-ray spectroscopy to probe the electronic structure of both the valence and conduction bands and compare our measurements to ab initio density functional theory calculations. We use several different exchange-correlation functionals, but find that no single theoretical approach used herein accurately quantifies both the band gap and the Ga 3d(10) states in LiGaO(2). We derive a band gap of 5.6 eV, and characterize electron hybridization in both the valence and conduction bands. Our study of the x-ray spectra may prove useful in analysing spectra from more complicated LiGaO(2) heterostructures.

Global oral health inequalities in incidence and outcomes for oral cancer: causes and solutions

The mouth and oropharynx are among the ten most common sites affected by cancer worldwide, but global incidence varies widely. Five-year survival rates exceed 50% in only the best treatment centers. Causes are predominantly lifestyle-related: Tobacco, areca nut, alcohol, poor diet, viral infections, and pollution are all important etiological factors. Oral cancer is a disease of the poor and dispossessed, and reducing social inequalities requires national policies co-ordinated with wider health and social initiatives - the common risk factor approach: control of the environment; safe water; adequate food; public and professional education about early signs and symptoms; early diagnosis and intervention; evidence-based treatments appropriate to available resources; and thoughtful rehabilitation and palliative care. Reductions in inequalities, both within and between countries, are more likely to accrue from the application of existing knowledge in a whole-of-society approach. Basic research aimed at determining individual predisposition and acquired genetic determinants of carcinogenesis and tumor progression, thus allowing for targeted therapies, should be pursued opportunistically.

Immunoexpression of matrix metalloproteinase-2 and matrix metalloproteinase-9 in the metastasis of squamous cell carcinoma of the human tongue

BACKGROUND

Squamous cell carcinoma of the tongue has frequent lymph node metastases and poor prognosis. Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) are reported to degrade basement membrane,facilitating invasion and metastasis. This study determined the expression of MMP-2/MMP-9 in primary tongue cancer with or without cervical metastases and analysed the significance of such expression in relation to the presence or absence of metastases.

METHODS

Expressions of MMP-2⁄MMP-9 were detected by immunohistochemistry in 10 specimens of normal oral mucosa, 20 lymph node-negative tongue cancers, 41 lymph node-positive tongue cancers and their metastasized tumours in cervical lymph nodes.

RESULTS

MMP-2⁄MMP-9 expression was seldom found in normal epithelium. In lymph node-negative tongue cancer, 45% and 40% of these primary tumours were positively stained for MMP-2⁄MMP-9, respectively. Importantly, in lymph node-positive tongue cancer, 71% and 79% of these primary tumours were positive for MMP-2⁄MMP-9, respectively. Overexpression of MMP-2⁄MMP-9 was present in the metastatic lymph nodes.

CONCLUSIONS

Our results imply that MMP-2 and/or MMP-9 play an important role in invasion and metastasis in tongue cancer, and that analysis of MMP expression and/or activity in primary tumours may have a predictive value for the actual or potential presence of cervical metastases.

Derivation and validation of a risk-factor model for detection of oral potentially malignant disorders in populations with high prevalence

BACKGROUND

Oral and pharyngeal cancers constitute the sixth most common type of cancer globally, with high morbidity and mortality. In many countries, most cases of oral cancer arise from long-standing, pre-existing lesions, yet advanced malignancies prevail. A new approach to early detection is needed. We aimed to validate a model for screening so that only high-risk individuals receive the clinical examination.

METHODS

A community-based case-control study (n=1029) in rural Sri Lanka assessed risk factors and markers for oral potentially malignant disorders (OPMD) by administering a questionnaire followed by an oral examination. We then developed a model based on age, socioeconomic status and habits of betel-quid chewing, alcohol drinking and tobacco smoking, with weightings based on odds ratios from the multiple logistic regression. A total, single score was calculated per individual. Standard receiver-operator characteristic curves were plotted for the total score and presence of OPMD. The model was validated on a new sample of 410 subjects in a different community.

RESULTS

A score of 12.0 produced optimal sensitivity (95.5%), specificity (75.9%), false-positive rate (24.0%), false-negative rate (4.5%), positive predictive value (35.9%) and negative predictive value (99.2%).

CONCLUSION

This model is suitable for detection of OPMD and oral cancer in high-risk communities, for example, in Asia, the Pacific and the global diaspora therefrom. A combined risk-factor score of 12.0 was optimal for participation in oral cancer/OPMD screening in Sri Lanka. The model, or local adaptations, should have wide applicability.

Primary head and neck cancers in North -Western Nigeria

BACKGROUND

Reported epidemiological studies on oro-facial cancers in Nigeria over the last four decades showed nonstandardized inclusion criteria and an overlap of study periods, resulting in conflicting findings.

OBJECTIVE

To document the pattern of reportable primary head and neck cancers in North-Western Nigeria and analyse Methods: A review of both clinical and histopathology records of head and neck cancers diagnosed by histopathology at the ABUTH, Zaria, was undertaken. Socio-demographic information and history of cancer management, which followed the pattern of the Minimum Cancer Dataset developed by the British Association of Head and Neck Oncologists, were retrieved from pathology and medical records of patients diagnosed of cancers of the head and neck at the hospital from January 1972 to December 2002.

RESULTS

A total of 2611 cases were diagnosed, 730 (28%) occurred in children, 1775 (68%) in adults, with 64% occurring at or below 40 years of age. The eye, 564(21.6%) and the mouth, 251(9.6%) were the most commonly affected sites. Carcinomas (55%), lymphomas (23%) and retino-blastomas (10%) were the most common cancers. Cancers of viral origin constituted 18% of head and neck cancers and AIDS-defining cancers were 6%. A significant increase was noted in the occurrence of conjunctival squamous cell carinoma (SCC) and Non-Hodgkins Lymphoma NHL when comparing the periods pre- and post- advent of HIV/ AIDS in Nigeria in 1986. Comparing the two periods, there was a reduction in the ages of occurrence of conjunctival SCC; Non-Hodgkins Lymphoma (NHL), Kaposis sarcoma (KS) and nasopharyngeal carcinoma, a rise in the occurrence of nasopharyngeal carcinoma and a significant drop in the occurrence of Burkitt lymphoma.

CONCLUSION

Reduced age at presentation and the rising prevalence of several virus-associated cancers suggests the role of immuno-suppression in the pathogenesis of these cancers. Further studies into nutritional and viral epidemiology in the population are desirable as the implication for prevention and public health policies are profound.

Primary head and neck cancers in Jos, Nigeria: a re-visit

BACKGROUND

To document the pattern of primary head and neck cancers in Jos, Nigeria.

STUDY DESIGN

A record-based study of head and neck cancers histologically diagnosed at the Jos University Teaching Hospital (JUTH), Jos, between January 1987 and December 2002.

RESULTS

A total of 710 cases (over 44 cases per year) were diagnosed, with a rising trend. The most common sites for cancer were the eyes (15.4%), lymph nodes (12.4 %), thyroid gland (11.8%) and the oral cavity (7.6%). Carcinomas 432(60.8%), lymphomas 119(16.8%) and sarcomas 105(14.8%) were the commonly reported cancers. Carcinomas were most commonly reported in the thyroid gland (19.2%), oral cavity (10.2%) and the eyes (9.5%). AIDS-related cancers constituted 12.3% of all head and neck cancers and were commonly reported in the 3rd decade of life. This is higher than the 10.9% and 7.6% previously reported for Jos (p=0.89) and Maiduguri (p=0.034) respectively. Carcinomas were associated with alcohol use and tobacco smoking (p<0.001), while kaposi sarcoma was more associated with HIV-positive patients than squamous cell carcinoma (p=0.016). The duration of symptoms for cancers varied with sites and cancer type but ranged from 6.5-89.7 months (mean= 37.7 +/- 51.1 months). 59 (93.7%) of the staged cancers reported in the late stages (III & IV). 48 (43.2%) of the treated cancers had primary surgery, while most lymphomas were treated with primary chemotherapy.

CONCLUSION

There is a rising trend in the occurrence of head and neck cancers in Jos, with a considerable proportion of the patients being below 30 years. The late presentation of patients, late stage at presentation, the rising profile of HIV/AIDS in the area and the non-availability of relevant specialists in the hospital could adversely affect the prognosis of these cancers.

(A2) Oral health and general health

The interactions between oral and systemic health are bi-directional and complex, involving many pathways. Regarding health as not merely the absence of disease, but as a state of total well-being, these interactions profoundly influence the progress of many diseases, and the quality of life and economic performance of HIV-infected individuals and populations. The evidence base for specific interactions is currently weak, partly because few good-quality studies have been published, partly because of the naïveté of the instruments currently available for recording these interactions and their inherent complexity. Recording quality of life should be a fundamental aspect of all future studies. The most significant conclusion of this Workshop is the need for all involved in oral health research and oral health care to be seen as, and to act as, essential partners in comprehensive care for whole patients and communities.

Tobacco cessation activities of UK dentists in primary care: signs of improvement

OBJECTIVE

To investigate attitudes and opinions of the members of the British Dental Association towards implementing tobacco cessation strategies in dental practices.

DESIGN AND METHOD

Questions about tobacco and tobacco cessation were asked on the September 2002 BDA Omnibus survey. The survey was sent out to a random sample of 1,500 BDA members, excluding retired members, overseas members and students. After two reminder circulations, 870 completed questionnaires were received, giving a response rate of 58%.

RESULTS

The survey results revealed good awareness amongst respondents of the health risks of tobacco. One fifth of respondents said that patients had asked them for advice on tobacco cessation. The majority (64%) of respondents stated that they gave advice on tobacco cessation 'fairly regularly' or 'always' (whether asked or not) and 37% of respondents recommended over-the-counter nicotine replacement therapy. Overall, 68% of respondents agreed that offering patients advice about tobacco cessation was the duty of every dentist. The most common barriers to a successful tobacco cessation campaign were perceived to be the amount of time required, lack of reimbursement, lack of training, lack of patient education materials and lack of knowledge of available referral resources. Nearly all respondents (92%) said that their practice was a completely smoke-free environment, and 66% of respondents had never used tobacco. The majority of respondents displayed patient education materials in their practice waiting/reception areas less than 60% of the time, and nearly a quarter (23%) never had them available. The survey revealed that most respondents did not feel particularly well prepared to assist patients in quitting tobacco, but 70% of respondents said they would be willing to cooperate with a campaign to inform all tobacco using patients about the advantages of tobacco cessation. Respondents felt that leaflets for patients, staff training and posters in the practice would contribute to the success of the campaign.

CONCLUSION

Members of the dental team are very willing to implement tobacco cessation strategies in the dental practice. Most dentists feel that promotion of tobacco cessation is an important part of the duty of a dentist, but they feel inadequately prepared to deliver such advice. The major barriers to delivering successful tobacco cessation campaigns are the amount of time required, lack of reimbursement, lack of training, lack of patient education materials and lack of knowledge of available referral resources. The majority of dentists have received no training in tobacco cessation strategies. They feel that staff training and free availability of more patient education materials (leaflets, posters, etc) would help promote the success of such a campaign.

Salivary gland neoplasms in Maiduguri, north-eastern Nigeria

OBJECTIVE

To document the pattern of salivary gland neoplasia in Maiduguri, Nigeria.

DESIGN AND SETTING

A retrospective clinical and histopathological review (January 1987-December 2002) of cases diagnosed at a tertiary care hospital.

MATERIALS AND METHODS

Information on demographics, diagnosis and cancer management in the hospital were retrieved from biopsy reports and case notes of patients.

RESULTS

The palatal (71.9%) and parotid (78.3%) glands were the most common minor and major salivary glands involved, with a benign-malignant ratio of 1:1 and 1.4:1, respectively. Pleomorphic adenoma (44.3%) was the most common salivary gland neoplasm recorded. It was commonly reported in the third decade (mean 30.4 years) and among males (M:F, 1.4:1). Ectopic lesions (17.1%) were reported in the neck, nose and cervical nodes. Mucoepidermoid carcinoma (10.1%) was the most common salivary gland malignancy, occurring in the second and sixth decades; of equal gender distribution and predominantly in the palate (50%). The squamous cell carcinoma (10.9%) and adenoidcystic carcinoma (21.9%) were the most common malignancies in the major and minor glands respectively. There was a higher prevalence of malignancies of the parotid than previously reported for northern Nigeria (P = 0.036).

CONCLUSION

Pleomorphic adenoma and mucoepidermoid carcinoma were the most commonly reported benign and malignant neoplasia in this series. The prevalence of mucoepidermoid carcinoma contrasts with reported findings in other African studies.

Intra-oral carcinomas in Maiduguri, north-eastern Nigeria

OBJECTIVE

To document the pattern of intra-oral carcinomas diagnosed in north-eastern Nigeria.

DESIGN AND SETTING

A retrospective clinical and histopathological review seen in a tertiary care hospital (January 1987-December 2002).

MATERIALS AND METHODS

Information on socio-demographic characteristics of patients and details of cancer management were retrieved from the files and histopathology records of cases diagnosed at the hospital.

RESULTS

A total of 378 biopsies, 317 primary cancers including 279 carcinomas of the head and neck were diagnosed during the study period. Intra-oral carcinomas constitute 43 (15.4%) of all head and neck carcinomas reported, with no occurrence in children. The overall mean age of occurrence was 51.2 +/- 15.6 years (male = 56.2 +/- 13.7 years; females = 47.5 +/- 16.2 years) and an overall male-female ratio of 3:4. Carcinomas were commonly reported in the palate 19 (44.2%) and lip six (13.9%) and floor of mouth four (9.3%). Squamous cell carcinoma 28 (65.1%), adenoidcystic carcinoma seven (16.3%) and mucoepidermoid carcinoma five (11.6%) were the commonly reported carcinomas. Squamous cell carcinoma was the most common carcinoma in all sites, in the sixth decade of life, of equal gender distribution and commonly reported in users of kola nuts and tobacco. The occupation of patients diagnosed with oral carcinoma and squamous cell carcinoma was farming (50%, 61.5%). All the staged cancers patients (n = 7) reported in the late stages (III/IV) of the disease. The mean interval between symptoms and presentation for the different carcinomas ranged between 9 and 25 months, with the least interval reported for mucoepidermoid carcinoma.

CONCLUSIONS

Squamous cell carcinoma was the most common oral carcinoma, commonly reported in the palate, among farmers and in the sixth decade of life. Its occurrence in under 40 year olds is three to six times greater than reported for the USA and Europe and may be associated with poor diet and the habitual use of kola nuts and tobacco. The survival rates of patients diagnosed with intra-oral carcinomas, although not available, would be expectedly low in view of the prognostic indicators recorded in this series. The routine oral cancer screening of each patient, and counselling of patients with high-risk habits, by dentists is recommended to improve the prognosis of the disease.

Primary head and neck cancers in North Eastern Nigeria

BACKGROUND

To document the pattern of primary head and neck cancers in North Eastern Nigeria.

STUDY DESIGN

A record-based study of primary head and neck cancers histologically diagnosed at the University of Maiduguri Teaching Hospital (UMTH), Maiduguri, North Eastern Nigeria between 1987 and 2002.

RESULTS

A total of 317 cases (20 cases per year) were diagnosed. The most common cancer sites were the oral cavity (15.1%) and nasopharynx (11.7%). Carcinomas (68.4 %) were the most common cancers reported, mostly affecting the oral cavity (20.3%). Carcinomas were associated with farmers, kola nut chewers and tobacco users in this region, while kaposi sarcoma was the only cancer associated with HIV-positive patients. The overall mean duration of symptoms for cancers was 29.1+/-62.2 months. The mean duration for carcinomas was longer than for sarcomas (p>0.05) and lymphomas (p= 0.05). 81 % of the staged cancers reported in the stage IV; while treated cancers required primary radiotherapy (51 %) or an adjuvant radical surgery and chemotherapy (9.4%).

CONCLUSION

Intra-oral carcinomas were the most common histological types of cancers in the head and neck. The delay before and the cancer stage at presentation may be due to the lack of cancer management facilities and manpower in most of the hospitals in the region.

Risk factors for oral cancer in newly diagnosed patients aged 45 years and younger: a case-control study in Southern England

BACKGROUND

This case-control study aimed to identify the risk factors for oral cancer in patients aged 45 years and under.

METHODS

Patients were recruited over a 3-year period between 1999 and 2001 from 14 hospitals in the southeast of England, UK.

RESULTS

Fifty-three (80%) newly diagnosed patients with squamous cell carcinoma (SCC) of the oral cavity participated. The mean age of cases at diagnosis was 38.5 years (SD = 7.0) and 53% were male. Patients were interviewed about main risk factors of tobacco, alcohol, cannabis and their consumption of fresh fruit and vegetables in the past. Ninety-one matched control patients were also recruited. Odds ratios (ORs) and 95% confidence intervals (CI) were obtained from adjusted conditional logistic analyses. Significantly elevated ORs were evidenced amongst males who had started to smoke under the age of 16 years (OR = 14.3; 95% CI: 1.1-178.8). A significant reduction in risk was also shown for ex-smokers (OR = 0.2; 95% CI: 0.5-0.8). Consumption of alcohol in excess of recommended amounts also produced an eightfold risk in males (OR = 8.1; 95% CI: 1.6-40.1) and over a fourfold risk of oral cancer from the consumption of excessive amounts of alcohol and having ever smoked (OR = 4.4; 95% CI: 1.1-17.7).

CONCLUSION

The study shows that the traditional behavioural risk factors are present in younger people diagnosed with oral cancer. The relatively short duration of exposure and the substantial number of cases without any known risk factors, particularly amongst females, however, suggest that factors other than tobacco and alcohol may also be implicated in the development of oral cancer in a proportion of these younger patients.