Blood flow restriction training in South Africa - a panel discussion

Background

Blood flow restriction (BFR) training uses a cuff to partially occlude venous blood flow and improve musculoskeletal training outcomes. Over the past 25 years, numerous studies have demonstrated its relative safety and efficacy.

Objectives

Blood flow restriction training is under review by the Health Professions Council of South Africa due to safety and ethical concerns. The objective of this roundtable discussion is to gain better insight into the current use and perception of blood flow restriction training in South Africa.

Formation of panel

The expert panel had experience with the use of BFR training and included one representative from each of the following professions, namely, sports medicine, physiotherapy and biokinetics.

Discussion

The panellists provided their unique perspectives on BFR training, whilst reaching a relative consensus on its safety, screening, efficacy, and appropriate use. Agreement on appropriate loading and occlusion pressure protocols during different phases of rehabilitation was less clear.

Conclusion

Although BFR is a safe and effective modality, the development of evidence-based protocols among different health professionals in South Africa is required to ensure good clinical practice.

The Monitor Practice Program: implications for dentistry and dental education

The restorative model of care, known colloquially as drilling and filling, has been challenged on the basis of its inappropriateness. The Caries Management System protocol was developed as an evidence-based strategy for non-surgical treatment of caries lesions and the Monitor Practice Program was designed to test the hypothesis that use of the protocol would reduce risk of dental caries experience. After 7 years, patients attending intervention practices, compared with those attending control practices, needed: 30%-50% fewer restorative interventions; 55% fewer first time restorative interventions; 32% fewer repeat restorative interventions; and were only 23% as likely to be classified as high risk. The outcome was cost-effective and patients attending intervention practices highly valued non-invasive care, and intervention dentists derived professional satisfaction from non-surgical caries management. The implications of the program are that the general public will likely embrace the benefits of non-invasive caries management, as will many current and future dental practitioners. This calls for dental practice reform including: the establishment of a clinical discipline in cariology; cariology curriculum development; revised accreditation regulations for cariology programs in dental schools; advanced training in clinical cariology leading to a specialty; support from the dental profession; and public health advocacy.

Deciduous dentition approximal caries lesion progression and regression following preventive treatment: literature review

The objective of this review was to investigate rates of caries lesion progression, arrest, and regression in approximal surfaces of deciduous teeth following secondary preventive interventions in order to inform caries management protocols. Studies published in English and other languages from 1960 till February 2017 were searched in electronic databases. Inclusion criteria were: randomized controlled clinical trials and longitudinal studies that involved non-invasive preventive treatment. We excluded: in vivo studies and incidence studies. 805 potential articles were located, of 38 full text reviews, 10 were included. Two types of studies were found; those reporting the mean percentage of lesion progression as progression estimate and those reporting the survival rate of lesions presented as the mean or median survival time in months as survival estimate. Weak evidence suggests it would appear that the most effective secondary preventive intervention was one involving a combination of silver fluoride and stannous fluoride, but this has not been substantiated. To inform treatment protocols better, it is recommended (i) that new well-designed RCTs are conducted to test the effectiveness of different forms of fluoride to arrest lesion progression in deciduous teeth and (ii) to continue ongoing research into the caries preventive effects of approximal surface sealants.

Glycaemic control modifies the haptoglobin 2 allele-conferred susceptibility to coronary artery disease in Type 1 diabetes

AIMS

We aimed to assess whether the association of the haptoglobin 2 allele with coronary artery disease is modified by glycaemic control in a prospective cohort study of individuals with childhood-onset Type 1 diabetes.

METHODS

Coronary artery disease events (death from coronary artery disease, confirmed myocardial infarction, stenosis ≥50%, revascularization) were assessed between 1986 and 2013 among 480 individuals with Type 1 diabetes (baseline age 28 years; diabetes duration 19 years). Better glycaemic control was defined as an updated mean HbA_1c during follow-up of <8% (64 mmol/mol).

RESULTS

In crude models, the incidence of coronary artery disease increased with the number of haptoglobin 2 alleles (hazard ratio 1.34, 95% CI 1.05-1.71). This association was more pronounced in those with better than in those with worse glycaemic control (P interaction = 0.05) and remained essentially unaltered after multivariable adjustments (hazard ratio 2.65, 95% CI 1.30-5.41 in those with better glycaemic control and hazard ratio 1.20, 95% CI 0.93-1.56 in those with worse glycaemic control).

CONCLUSIONS

These results suggest that, although better control may reduce the incidence of coronary artery disease in Type 1 diabetes, a residual risk related to the haptoglobin 2 allele remains.

The Associations of C-Reactive Protein with Serum Levels of Polyunsaturated Fatty Acids and Trans Fatty Acids Among Middle-Aged Men from Three Populations

BACKGROUND

C-reactive protein (CRP) and many fatty acids (FAs) have been linked to cardiovascular disease. Associations of serum CRP with FAs in different populations have not been established.

METHODS

Participants were 926 men aged 40-49 (2002-2006) from a population-based sample; 310 Whites from Pennsylvania, U.S., 313 Japanese from Shiga, Japan, and 303 Japanese Americans from Hawaii, U.S. Serum CRP (mg/L) was measured using immunosorbent assay while serum FAs (%) were measured using capillary-gas-liquid chromatography.

RESULTS

Whites had CRP (mg/L) levels higher than Japanese with Japanese Americans in-between (age-adjusted geometric mean "GM" 0.96, 0.38, 0.66, respectively). Whites had also higher levels of total n-6 FAs (%) and trans fatty acids (TFAs) but lower levels of marine-derived n-3 FAs compared to Japanese (41.78 vs. 35.05, 1.04 vs. 0.58, and 3.85 vs. 9.29, respectively). Japanese Americans had FAs levels in-between the other two populations. Whites had significant inverse trends between CRP and tertiles of total n-6 FAs (GM 1.20, 0.91 and 0.80; p=0.002) and marine-derived n-3 FAs (GM 1.22, 1.00 and 0.72; p<0.001) but a significant positive trend with TFAs (GM 0.80, 0.95 and 1.15; p=0.007). Japanese had a significant inverse trend between CRP and only total n-6 FAs (GM 0.50, 0.35 and 0.31; p<0.001). Japanese Americans had CRP associations with n-3 FAs, n-6 FAs, and TFAs similar to but weaker than Whites.

CONCLUSIONS

With the exception of consistent inverse association of CRP with total n-6 FAs, there are considerable variations across the three populations in the associations of CRP with different FAs.

Small-for-gestational-age birth and maternal plasma antioxidant levels in mid-gestation: a nested case-control study

OBJECTIVE

To assess whether maternal plasma antioxidant levels in mid-pregnancy are associated with small-for-gestational-age (SGA) birth.

DESIGN

Case-control study nested within a population-based cohort study.

SETTING

Four hospitals in Montreal, Canada.

POPULATION

Pregnant women recruited before 24 weeks of gestation, whose pregnancies were not complicated by pre-eclampsia or preterm delivery.

METHODS

Blood samples were obtained at 24-26 weeks and assayed for nutritionally derived antioxidant levels in SGA cases (n = 324) and randomly selected controls with birthweights between the 25th and 75th centiles (n = 672). We performed logistic regression analyses using the standardised z-score of each antioxidant as the main independent variable, after summing highly correlated antioxidants or combining via principle component analysis. We adjusted for risk factors for SGA that were associated with antioxidant levels.

MAIN OUTCOME MEASURES

SGA, birthweight <10th centile for gestational age and sex.

RESULTS

Retinol was positively associated with risk of SGA (adjusted odds ratio [OR] 1.41; 95% confidence interval [95% CI] 1.22-1.63, per SD increase). Carotenoids (log of the sum of β-carotene, lutein/zeaxanthin, α- and β-cryptoxanthin) were negatively associated with SGA (adjusted OR 0.64; 95% CI 0.54-0.78, per SD increase). We found no significant associations between SGA and lycopene or any of the forms of vitamin E assessed, including α-tocopherol, corrected α-tocopherol (per nmol/l of low-density lipoprotein articles), or γ-tocopherol.

CONCLUSIONS

Elevated retinol may be associated with an increased risk of SGA, whereas elevated carotenoid levels may reduce the risk. A better understanding of the nature of these associations is required, however, before recommending specific nutritional interventions in an attempt to prevent SGA birth.

Skeletal muscle adiposity is associated with serum lipid and lipoprotein levels in Afro-Caribbean men

OBJECTIVE

When compared with other ethnic groups, African ancestry individuals have lower triglycerides and higher High-density lipoprotein cholesterol (HDL-C) levels, although the mechanisms for these differences remain unclear. A comprehensive array of factors potentially related to fasting serum lipid and lipoprotein levels in African ancestry men was evaluated.

DESIGN AND METHODS

Men (1,821) underwent dual-energy X-ray absorptiometry measures of total body fat and quantitative computed tomography assessments of calf skeletal muscle adiposity [subcutaneous and intermuscular adipose tissue (AT), and muscle density as a measure of intra-muscular AT].

RESULTS

Multivariable linear regression analysis identified age (-), total body fat (+), subcutaneous AT (-), fasting glucose (+), fasting insulin (+), diastolic blood pressure (+), and non-African ancestry (+) as independent correlates of triglycerides (all P < 0.05). Total body fat (+), intra-muscular AT (-), and diastolic blood pressure (+) were independent correlates of Low-density lipoprotein cholesterol (LDL-C) (all P < 0.001). Age (+), waist circumference (-), fasting insulin (-), physical activity (+), and alcohol intake (+) were independent correlates of HDL-C (all P < 0.05).

CONCLUSIONS

A novel relationship between skeletal muscle adiposity and serum lipid and lipoprotein levels in African ancestry men, independent of total and central adiposity was illuminated. In African ancestry populations, genetic factors are likely a significant determinant of triglycerides levels.

Serum lipids and their associations with viral levels and liver disease severity in a treatment-naïve chronic hepatitis C type 1-infected cohort

In patients with chronic hepatitis C virus (HCV) infection, steatosis and fibrosis have been shown to be inversely associated with total cholesterol (TC) and low-density lipoprotein cholesterol. Steatosis and fibrosis have also been found to be associated with triglyceride (TG) levels; though, the direction of the relationship is inconsistent across studies. The objective of this study was to assess whether viral level and histological factors are associated with the serum lipid profile in a treatment-naïve cohort with chronic HCV genotype 1 infection. Participants were from the prospective Study of Viral Resistance to Antiviral Therapy (Virahep-C). Fasting lipid profiles were analysed for 160 African Americans and 170 Caucasian Americans. Linear regression was used to evaluate associations of each lipid with viral load and liver disease. TG levels were significantly and directly associated with HCV levels (P = 0.0034) and steatosis (P < 0.0001). Other lipid parameters were significantly lower in those with fibrosis [HDLc (P = 0.001) and TC levels (P = 0.004)] than in those without fibrosis. In patients with HCV genotype 1 infection, more severe liver disease was associated with lower lipid levels, with the exception of TG levels that were directly related to steatosis. The direct relationship between viral load and TG levels is consistent with proposed the mechanisms of very low density lipoprotein/HCV particle secretion. In contrast, the direct relationship between TG level and steatosis is inconsistent with posited mechanisms of HCV-induced steatosis, a possible reflection of HCV genotype 1 infection and a metabolic aetiology of steatosis.

The Monitor Practice Programme: is non-invasive management of dental caries in private practice cost-effective?

BACKGROUND

The objective of this research was to assess the efficacy and cost-effectiveness of a non-invasive approach to dental caries management in private dental practice.

METHODS

Private dental practices from a variety of locations in New South Wales were randomly allocated to either non-invasive management of caries, or continue with usual care. Patients were followed for three years and caries incidence assessed. A patient-level decision analytic model was constructed to assess the cost-effectiveness of the intervention at two years, three years, and hypothetical lifetime.

RESULTS

Twenty-two dental practices and 920 patients were recruited. Within the clinical trial there was a significant difference in caries increment favouring non-invasive therapy at both two and three years. Efficacy was independent of age, gender, medical concerns, fluoride history, or previous history of dental caries, in a population of patients attending for treatment in private dental practices, in a variety of locations both urban and rural. Cost per DMFT avoided estimate was A$1287.07 (two years), A$1148.91 (three years) decreasing to A$702.52 in (medium) and A$545.93 (high) risk patients (three years).

CONCLUSIONS

A joint preventive and non-invasive therapeutic approach appears to be cost-effective in patients at medium and high risk of developing dental caries when compared to the standard care provided by private dental practice.

Water fluoridation in the Blue Mountains reduces risk of tooth decay

BACKGROUND

In April 1992, the fluoride concentration in the Blue Mountains water supply was adjusted to 1 mg/L. Baseline dmft/DMFT has been determined in children attending schools in the region and in the adjacent reference region of Hawkesbury, fluoridated since 1968. The aim of this study was to evaluate the effect of the water fluoridation programme in the Blue Mountains.

METHODS

In 2003, children attending the same schools were sampled. Residential history data were obtained by questionnaire and caries experience was assessed according to WHO guidelines. The analysis was restricted to lifelong resident children aged 5-11 years.

RESULTS

The baseline and follow-up dmft scores for Blue Mountains children aged 5-8 years were 2.36 and 0.67, respectively. The age-adjusted decrease in odds of experiencing one or more dmft due to fluoridation was 0.26 (CI(95) 0.19, 0.37). The corresponding DMFT scores for Blue Mountains children aged 8-11 were 0.76 and 0.21 and the corresponding decrease in odds of experiencing one or more DMFT due to fluoridation was 0.25 (CI(95) 0.16, 0.40).

CONCLUSIONS

Tooth decay reduction observed in the Blue Mountains corresponds to high rates reported elsewhere and demonstrates the substantial benefits of water fluoridation.

Dental students' knowledge and perceptions of non-invasive dental caries management

BACKGROUND

An evidence-based, risk-specific, and non-invasive modality for caries management was implemented in the University of Sydney dentistry curriculum. This study reviews its impact on student learning outcomes and their perceptions of the efficacy of a risk-based caries management.

METHODS

One hundred and nine Year 3 and Year 4 students were invited to complete a questionnaire to assess their understanding of the protocols and their perceptions of both the education process and value of the non-invasive treatment modality.

RESULTS

A response rate of 93% Year 3 and 46% Year 4 students was obtained. They correctly identified high and low risk cases but Year 3 students were inclined to misclassify medium risk cases. Most understood correctly that enamel lesions should be arrested and remineralized but were often more radical in dealing with dentine lesions. Students who believed the protocols were useful and who spent more time on preventive care were less likely to restore enamel and dentine lesions.

CONCLUSIONS

A modest level of knowledge concerning application of the non-invasive caries management system to paper-based clinical case studies was demonstrated. Protocol misinterpretation may reflect inconsistent instruction by some clinical tutors. It is hoped that the promulgation of evidence-based dentistry will overcome these barriers in future.

Temporal patterns in overweight and obesity in Type 1 diabetes

AIMS

Time trends in overweight and obesity in the general population have been well documented; however, temporal patterns in Type 1 diabetes (T1DM) have not been thoroughly investigated. We therefore assessed temporal patterns in overweight and obesity and predictors of weight change in 589 individuals from the Pittsburgh Epidemiology of Diabetes Complications Study, a cohort of childhood-onset T1DM.

METHODS

Participants were first seen in 1986-1988, when mean age and diabetes duration were 29 and 20 years, respectively, and biennially thereafter for 18 years. Overweight was defined as 25.0or=30.0 kg/m2.

RESULTS

At baseline, the prevalence of overweight and obesity were 28.6% and 3.4%, respectively. After 18 years' follow-up, the prevalence of overweight increased by 47% while the prevalence of obesity increased sevenfold. Seven per cent were on intensive insulin therapy (>or=3 insulin injections per day or on insulin pump) at baseline; by 2004-2007, this was 82%. Predictors of weight change were a higher baseline HbA1c, symptomatic autonomic neuropathy (inversely), overt nephropathy (inversely), and going onto intensive insulin therapy during follow-up.

CONCLUSIONS

These data demonstrate dramatic weight gain in T1DM and underscore the complexity of weight change in this disease.

Association analysis of 33 lipoprotein candidate genes in multi-generational families of African ancestry

African ancestry individuals have a more favorable lipoprotein profile than Caucasians, although the mechanisms for these differences remain unclear. We measured fasting serum lipoproteins and genotyped 768 tagging or potentially functional single nucleotide polymorphisms (SNPs) across 33 candidate gene regions in 401 Afro-Caribbeans older than 18 years belonging to 7 multi-generational pedigrees (mean family size 51, range 21-113, 3,426 relative pairs). All lipoproteins were significantly heritable (P<0.05). Gender-specific analysis showed that heritability for triglycerides was much higher (P<0.01) in women than in men (women, 0.62+/-0.18, P<0.01; men, 0.13+/-0.17, P>0.10), but the heritability for LDL cholesterol (LDL-C) was higher (P<0.05) in men than in women (men, 0.79+/-0.21, P<0.01; women, 0.39+/-0.12, P<0.01). The top 14 SNPs that passed the false discovery rate threshold in the families were then tested for replication in an independent population-based sample of 1,750 Afro-Caribbean men aged 40+ years. Our results revealed significant associations for three SNPs in two genes (rs5929 and rs6511720 in LDLR and rs7517090 in PCSK9) and LDL-C in both the family study and in the replication study. Our findings suggest that LDLR and PCSK9 variants may contribute to a variation in LDL-C among African ancestry individuals. Future sequencing and functional studies of these loci may advance our understanding of genetic factors contributing to LDL-C in African ancestry populations.

A survey of family doctors on the likeability of migraine and other common diseases and their prevalence of migraine

A survey of 148 family doctors attending a continuing medical education migraine update lecture was performed to assess whether family doctors like to treat migraine and other common disorders and the prevalence of migraine. Doctors were asked to respond to the following statement using a five-point Likert scale (from 1, strongly disagree to 5, strongly agree): 'I like to treat patients with this disease or symptom'. The response rate was 53% with a mean age of 51.5 years. Doctors reported liking to treat general medical conditions more (mean = 4.40) than migraine (mean = 3.38) and other neurological diseases (mean = 3.20). Doctors reported a personal history of migraine in the prior 1 year of 22.8% and 45.6% lifetime, with 17% becoming aware for the first time that they personally had migraine after attending the lecture. Respondents with a personal history of migraine liked to treat migraine more than those without a history.

The Monitor Practice Programme: is non-invasive management of dental caries in private practice effective?

BACKGROUND

This paper reviews the efficacy of an intensive, preventive-based, non-invasive approach to the management of dental caries within a randomized controlled trial.

METHODS

The primary efficacy measure was the two-year DMFS increment. Changes in risk status, fluoride history, number of emergency visits and toothaches, along with demographic variables such as age, gender, health problems, and the location of the dental practice attended were measured. Regression analysis was undertaken to adjust for potential confounding variables.

RESULTS

Nine hundred and two patients were recruited within 22 dental practices between May 2005 and March 2006. Baseline DMFS did not differ significantly between the control and study groups (p = 0.83). Age (p < 0.001), health status (p = 0.005), baseline risk (p < 0.001) and fluoride history (p < 0.001) were all independent significant predictors of two-year DMFS increment. Gender approached significance (p = 0.08). There were no statistically significant differences between the groups in the incidence of toothaches (p = 0.1) or number of treatment visits required (p = 0.35). There was a significant difference in the two-year incremental DMFS score in the study group compared to the control group (mean difference 2.2; p < 0.001). After adjusting for confounding variables the difference in the DMFS increment between the control and study groups remained significant (mean difference 1.7; p < 0.001).

CONCLUSIONS

The results indicate efficacy of the preventive programme. Efficacy was independent of age, gender, medical concerns, fluoride history, or previous history of dental caries, in a population of patients attending for treatment in private dental practices, in a variety of locations, on a relatively short-term basis (two years). While encouraging, it will be essential that these results are followed over a longer period of time in order to determine whether the benefits are maintained.

Caries risk reduction in patients attending a caries management clinic

BACKGROUND

A Caries Management Clinic was established for patients at high risk of caries aiming to reduce caries incidence to close to zero. That is, to prevent new lesions on existing sound surfaces, along the susceptible restoration margins, and to remineralize existing cavitated and non-cavitated lesions. Twenty patients attended the clinic every two weeks from April to December 2005.

METHODS

The Caries Management System is a ten-step non-invasive strategy to arrest and remineralize early lesions and includes consideration of the patient at risk, the status of each individual lesion, patient management, clinical management, and monitoring.

RESULTS

After six months, there was a 42 per cent increase in gingival sites having Gingival Index scores of zero, and a 21 per cent decrease in sites having Gingival Index scores of 2 compared to baseline (chi(2 )=( )137.67, 4 df, p = 0.00001). Ready to change (RTC) patients had significantly fewer sites scored GI <or= 2 compared to not-RTC patients (p = 0.01). Compared with the not-RTC patients, RTC patients were more than twice as likely to have fewer sites scored GI </= 2 (RR = 2.43, 95% CI (1.24, 4.71), p = 0.01). A total of 100 out of 146 smooth non-cavitated carious surfaces at baseline have remineralized after six months, 99 per cent of sound surfaces remained sound, and 23 new lesions were observed in six of the 20 patients (alpha(2 )=( )292, 7 df, p = 0.00001). About half of proximal surfaces showing bitewing scores of grade 1 or 2 had regressed (alpha(2 )=( )86.66, 56 df, p = 0.0001) and 95 per cent of proximal sound surfaces at baseline, as diagnosed via bitewing radiographs, remained sound.

CONCLUSIONS

This audit revealed that the implementation of the non-invasive approach to caries management which combined intensive coaching in oral hygiene maintenance, special home care and intensive monitoring in a clinic for high-risk patients was able to reduce gingival inflammation and maintain low plaque levels, at least within the scope of this short-term review.

Ethnocentrism is an unacceptable rationale for health care policy: a critique of transplant tourism position statements

Medical tourism has emerged as a global health care phenomenon, valued at $60 billion worldwide in 2006. Transplant tourism, unlike other more benign forms of medical tourism, has become a flashpoint within the transplant community, underscoring the uneasy relationships among science, religion, politics, ethics and international health care policies concerning the commercialization of transplantation. Numerous professional associations have drafted or issued position statements condemning transplant tourism. Often the criticism is misdirected. The real issue concerns both the source and circumstances surrounding the procurement of donor organs, including commercialization. Unfortunately, many of the position statements circulated to date represent an ethnocentric and decidedly western view of transplantation. As such, the merits of culturally insensitive policy statements issued by otherwise well-intended transplant professionals, and the organizations they represent, must be evaluated within the broader context of foreign relations and diplomacy, as well as cultural and ethical relativity. Having done so, many persons may find themselves reluctant to endorse statements that have produced a misleading social desirability bias, which, to a great extent, has impeded more thoughtful and inclusive deliberations on the issues. Therefore, instead of taking an official position on policy matters concerning the commercial aspects of transplantation, international professional associations should offer culturally respectful guidance.

The Caries Management System: an evidence-based preventive strategy for dental practitioners. Application for adults

In the absence of effective caries preventive methods, operative care became established as the means for caries control in general practice. Water fluoridation resulted in a declining caries incidence which decreased further following the advent of fluoridated toothpaste. The challenge today is to develop a non-invasive model of practice that will sustain a low level of primary caries experience in the younger generation and reduce risk of caries experience in the older generations. The Caries Management System is a ten step non-invasive strategy to arrest and remineralize early lesions. The governing principle of this system is that caries management must include consideration of the patient at risk, the status of each lesion, patient management, clinical management and monitoring. Both dental caries risk and treatment are managed according to a set of protocols that are applied at various steps throughout patient consultation and treatment. The anticipated outcome of implementing the Caries Management System in general dental practice is reduction in caries incidence and increased patient satisfaction. Since the attainment and maintenance of oral health is determined mainly by controlling both caries and periodontal disease, the implementation of the Caries Management System in general practice will promote both outcomes.

Geographic location and indirect costs as a barrier to dental treatment: a patient perspective

BACKGROUND

The recently published National Survey of Adult Oral Health 2004-06 indicated that tooth loss, mean decayed and number of DMF teeth were all higher outside capital city locations. In addition, dental attendance patterns were worse in terms of frequency, reason for visit, and continuity in rural and remote locations, but there was no difference by geographical location in terms of financial barriers to dental care. The objective of this research was to identify, quantify and analyse some of the non-treatment costs associated with dental treatment from the perspective of the patient and to determine whether the perceived impact of those costs may limit access to dental care.

METHODS

This cohort study was nested within a clinical trial. Patients had been allocated to treatment arms within clusters dependent on the randomization status of the dental practice they usually attended, classified as major city, regional or remote. A questionnaire was developed from a series of focus groups in which patients were asked to identify the domains of non-treatment costs associated with a dental visit that were important to them and to quantify those costs. Factor analysis was used to reduce these items to four core scales. These scales were assessed for reliability and validity. Regression and ANCOVA was used to explore differences in DMFS scores between the three groups and a predictive model developed to adjust for potential confounders.

RESULTS

Two core scales were identified as key drivers on the perceived impact of indirect costs associated with dental visits; travel impact and family impact. Patients living in remote locations incurred significantly higher indirect costs associated with dental treatment and higher mean DMFS scores.

CONCLUSIONS

Patient perception of the impact of travel costs and impact on family life are major drivers restricting access to dental services for people living in remote locations in New South Wales. Further research using outcomes directly related to access is required to validate the claim that patients living in regional and remote locations suffer both perceived and real financial barriers to dental care.

Calibration of magnetic probes in the vicinity of a conducting well

Measuring magnetic fields near the edge of a plasma device can be complicated by the geometric effects of the ports through which such measurements are made. The primary effect is an attenuation of the magnetic field at the probe coil due to the field expanding into the finite sized conducting well of the port. In addition, it is possible to determine the correspondence between the location of a field line as it intersects the probe coil inside the well, with its location far from the perturbation of the well. Here we explore several methods of experimentally characterizing the magnetic fields in the vicinity of the magnetic probe ports of a vacuum vessel, with the aim of improving the interpretation of magnetic measurements needed for experiments in plasma physics.

Recruitment and standardization of a group of Australian dentists for a multipractice study on dental caries prevention

BACKGROUND

This introductory paper details the recruitment and standardization of a group of dentists participating in a clinical trial. The trial is being undertaken to determine the cost-effectiveness of a structured preventive programme compared to standard care within private dental practices. We recruited private dental practitioners from a variety of locations in New South Wales (NSW) and the Australian Capital Territory (ACT). We sought to quantify the diagnostic reliability of dentists involved, and to define, quantify, and analyse standard care.

METHODS

This is a multi-centre, clustered randomized controlled trial, where dentists are allocated to an intervention preventive or control group. Recruitment was facilitated with the support of key stakeholders and included oral presentations at divisional meetings of the Australian Dental Association, NSW Branch (ADA). A detailed time-in-motion study of 426 dental procedures was undertaken in order to define the parameters of standard care. The reliability study involved each dentist reading a set of 12 pairs of bitewing radiographs that had been produced and reviewed under standardized conditions. The reliability analysis was undertaken blind to allocation status of the dentist.

RESULTS

Recruitment ceased three months into the planned six-month recruitment period, 31 practices having approached the researchers. Eight suburban, five Central Business District (CBD), five rural (in fluoridated communities), and four rural (in non-fluoridated communities) practices have been recruited. Standard care did not differ significantly between intervention and control practices (Mann-Whitney U: z = -0.50; P = 0.6). Diagnostic reliability was substantial (Kappa = 0.79 [range 0.73-0.811 and 0.78 [range 0.72-0.82]) in relation to the intervention and control practices, respectively; P = 0.6.

CONCLUSION

The involvement of private dental practices in research is feasible and well supported by the profession. Standard care does not differ significantly between intervention and control practices. Inter- and intra-observer reliability was substantial, and not statistically different between the two arms of the trial.

The mechanism of iron uptake by transferrins: the structure of an 18 kDa NII-domain fragment from duck ovotransferrin at 2.3 A resolution

The molecular structure of an iron-containing 18 kDa fragment of duck ovotransferrin, obtained by proteolysis of the intact protein, has been elucidated by protein crystallographic techniques at 2.3 A resolution. This structure supports a mechanism of iron uptake in the intact protein whereby the binding of the synergistic (bi)carbonate anion is followed by binding of the metal with the lobe in the open configuration. These stages are then followed by domain closure in which the aspartic acid residue plays a further key role, by forming an interdomain hydrogen-bond interaction in addition to serving as a ligand to the iron. This essential dual role is highlighted by model building studies on the C-terminal lobe of a known human variant. In this variant a mutation of a glycine by an arginine residue enables the aspartic acid to form an ion pair and reduce its effectiveness for both metal binding and domain closure. The X-ray structure of the 18 kDa fragment strongly suggests that the histidine residue present at the iron binding site of the intact protein and arising from the second interdomain connecting strand has been removed during the preparative proteolysis.

The prospective association between adiponectin and coronary artery disease among individuals with type 1 diabetes. The Pittsburgh Epidemiology of Diabetes Complications Study

AIMS/HYPOTHESIS

Recent findings suggest the potential involvement of adiponectin in obesity, diabetes and cardiovascular disease. We assessed the prospective association between adiponectin concentration and coronary artery disease in individuals with type 1 diabetes.

METHODS

Participants were identified from the Pittsburgh Epidemiology of Diabetes Complications cohort, a prospective follow-up study of childhood-onset type 1 diabetes. At baseline, subjects had a mean age of 28 years, and a mean diabetes duration of 19 years. Cases (determined by physician-diagnosed angina, confirmed myocardial infraction, stenosis >or=50%, ischemic ECG or revascularization) were matched to the control subjects with respect to sex, age and diabetes duration. Samples and risk factors for analyses were identified from the earliest exam prior to incidence in cases. Sera and information on all covariates were available for 28 cases and 34 control subjects. Proportional hazards models were constructed including matching variables.

RESULTS

Compared with those in men, adiponectin concentrations were elevated in females (p=0.009) and among individuals with macroalbuminuria (p=0.04). In multivariable analyses (adjusting for standard risk factors as well as lipoprotein measurements determined by nuclear magnetic resonance spectroscopy, E-selectin or antioxidants), adiponectin inversely predicted the incidence of coronary artery disease (hazard ratio=0.37 per 1 SD increase, 95% CI 0.19-0.73, p=0.004).

CONCLUSIONS/INTERPRETATION

The results suggest that increased adiponectin concentration is prospectively associated with a lower risk of coronary artery disease type 1 diabetes. The potential of adiponectin determination as a useful marker of, and potential therapeutic target for, coronary artery disease prevention in type 1 diabetes should be further explored.

The plug domain of a neisserial TonB-dependent transporter retains structural integrity in the absence of its transmembrane beta-barrel

Transferrin binding protein A (TbpA) is a TonB-dependent outer membrane protein expressed by pathogenic bacteria for iron acquisition from human transferrin. The N-terminal 160 residues (plug domain) of TbpA were overexpressed in both the periplasm and cytoplasm of Escherichia coli. We found this domain to be soluble and monodisperse in solution, exhibiting secondary structure elements found in plug domains of structurally characterized TonB-dependent transporters. Although the TbpA plug domain is apparently correctly folded, we were not able to observe an interaction with human transferrin by isothermal titration calorimetry or nitrocellulose binding assays. These experiments suggest that the plug domain may fold independently of the beta-barrel, but extracellular loops of the beta-barrel are required for ligand binding.

Maternal and fetal amino acid concentrations and fetal outcomes during pre-eclampsia

The pathophysiology of pre-eclampsia is contested, but one hypothesis indicates that it is a heterogeneous condition in which only a subset of affected women bear small-for-gestational age (SGA) babies. In intrauterine growth-restricted (IUGR) infants, placental transport of amino acids is diminished and the resulting decrease in cord-blood amino acid concentrations is thought to contribute to their stunted growth. In contrast, the metabolic syndrome (dyslipidaemia, hyperinsulinaemia, hyperglycaemia, hypertension and obesity) which is associated with high amino acid concentrations is more prevalent in women with pre-eclampsia. The focus of this study was to compare maternal and fetal serum amino acid concentrations during normal pregnancy and pre-eclampsia and to evaluate the associations between the amino acid concentrations and fetal growth. The results indicate that maternal and cord-blood amino acid concentrations were significantly higher in women with pre-eclampsia compared with normal pregnant women and the concentrations were inversely associated with measures of infant growth. Maternal and cord-blood amino acid concentrations were also significantly higher in pre-eclamptic mothers with SGA infants compared with pre-eclamptic mothers whose babies were not SGA. These data indicate that, in contrast to IUGR, pre-eclampsia is associated with enhanced placental amino acid transport or reduced fetal amino acid utilization. Furthermore, the data are consistent with the hypothesis that pre-eclampsia is a heterogeneous disease associated with the metabolic syndrome.

Lipoprotein subclass measurements by nuclear magnetic resonance spectroscopy improve the prediction of coronary artery disease in Type 1 diabetes. A prospective report from the Pittsburgh Epidemiology of Diabetes Complications Study

AIM/HYPOTHESIS

To examine whether nuclear magnetic resonance lipoprotein spectroscopy improves the prediction of coronary artery disease in patients with Type 1 diabetes, independently of conventional lipid and other risk factors.

METHODS

A prospective nested case-control design of subjects with childhood onset Type 1 diabetes from the Pittsburgh Epidemiology of Diabetes Complications Study was used. 59 controls were age-, sex- and duration-matched to 59 incident cases of coronary artery disease (fatal or non-fatal myocardial infarction, angina, coronary stenosis >50%) occurring during 10 years of follow-up. Lipid mass and particle concentrations of VLDL, LDL, and HDL subclasses, grouped into three size categories (large, medium, and small), were assessed prior to event with nuclear magnetic resonance spectroscopy.

RESULTS

Univariate analyses showed that both lipid mass and particle concentrations of all three VLDL subclasses, small LDL, medium LDL, and medium HDL were increased in CAD cases compared to controls, while large HDL was decreased. Mean LDL and HDL particle sizes were lower in cases. In multivariate models using conventional lipid and non-lipid risk factors, triglycerides and overt nephropathy were the strongest predictors of CAD. Nuclear magnetic resonance measures further improved the prediction, i.e. large HDL particle concentration (OR=0.43, p=0.030), medium HDL mass (OR=3.79, p=0.026) and total VLDL particle concentration (OR=2.33, p=0.033).

CONCLUSION/INTERPRETATION

While these results underscore the importance of triglycerides and overt nephropathy in CAD risk in Type 1 diabetic patients, they also suggest that nuclear magnetic resonance lipoprotein spectroscopy could further refine its prediction and show novel findings concerning HDL subclasses.

Transferrin-mediated iron acquisition by pathogenic Neisseria

The pathogenic Neisseria have a siderophore-independent iron-uptake system reliant on a direct interaction between the bacterial cell and transferrin. In the meningococcus this uptake system is dependent on two surface-exposed transferrin-binding proteins. This short account will review our current knowledge of the transferrin-mediated iron-acquisition system of pathogenic Neisseria.

Costs and insurance coverage associated with permanent mechanical cardiac assist/replacement devices in the United States

Each year over 50,000 persons in the United States could potentially benefit from some form of permanent cardiac replacement or assistance. Approximately 7000 of these persons get on the waiting list for a transplant, and 2300 are transplanted. About 2000 patients are reportedly exposed to a mechanical cardiac assist device, most often as a bridge to transplant. The majority of persons who might benefit from cardiac replacement are never referred for treatment and, thus, the number of deaths on the waiting list is a misleading indicator of access to transplantation and overall patient mortality. The total economic burden associated with coronary artery disease and congestive heart failure now exceeds $140 billion each year, with approximately $700 million directly spent on heart transplant procedures alone. If a viable total artificial heart is devised to replace a failed heart, or a ventricular assist system to permanently assist a failing heart, direct aggregate expenditures alone are likely to be somewhere between $5.4 and $24.0 billion annually. Based on individual patient care costs, as well as aggregate national expenditures, insurers will be reluctant to pay for the permanent use of such devices, even though cost is reportedly not a consideration in coverage decisions. Today, medical benefits and added value are concepts that will shape the coverage determination process, as will increasingly liberal policies regarding payment for treatment costs in relationship to clinical trials. Nonetheless, resource allocation and rationing decisions loom large as strange "characters at play" on an international economic "stage," while being "directed" by worldwide health care needs.

Homocysteine and cellular fibronectin are increased in preeclampsia, not transient hypertension of pregnancy

OBJECTIVE

The objective of this study was to confirm that endothelial dysfunction is present in preeclampsia and absent in transient hypertension of pregnancy, and to determine whether the cardiovascular risk factor homocysteine is associated with the degree of endothelial dysfunction.

METHODS

We measured cellular fibronectin (as a marker of endothelial injury) and total plasma homocysteine in samples collected at the time of admittance to labor and delivery in 17 women with preeclampsia (increased blood pressure, proteinuria, and hyperuricemia), 16 women with transient hypertension of pregnancy (only increased blood pressure), and 34 normal pregnant women. Each subject with preeclampsia was matched by prepregnancy body mass index, race, and gestational age at delivery to one subject with transient hypertension of pregnancy and two controls.

RESULTS

Cellular fibronectin was found to be significantly increased in women with preeclampsia compared to subjects with transient hypertension of pregnancy or normal pregnant women (22.9 +/- 14.1 microg/mL versus 10.9 +/- 5.4 and 10.1 +/- 6.2 microg/mL, respectively, p<0.0001). Similarly, total plasma homocysteine was also significantly increased in the women with preeclampsia compared to subjects with transient hypertension of pregnancy or normal pregnant women (8.3 +/- 2.5 microM versus <5.5 +/- 2.2 and 5.4 +/- 3.4 microM respectively, p<0.01). However, contrary to our hypothesis, there was no apparent association between cellular fibronectin and homocysteine.

CONCLUSIONS

The increased concentrations of homocysteine observed in preeclampsia are not a general feature of all hypertensive complications of pregnancy. Furthermore, endothelial dysfunction is present in preeclampsia and is not evident in transient hypertension of pregnancy. However, the apparent endothelial dysfunction in preeclampsia is not explained by the increase in homocysteine concentrations observed.

Caries, bitewings, and treatment decisions

BACKGROUND

The most common adjunct to the visual and tactile clinical examination for dental caries is the bitewing radiograph. The aim of this study was to report on treatment planning decisions made by Victorian dentists when given a range of predetermined radiographic scenarios.

METHODS

A postal survey was conducted to obtain data from 550 dentists selected systematically (every fourth dentist) from the register of the Dental Board of Victoria (1996).

RESULTS

The survey response rate was 64 per cent. Fifty per cent of responding dentists selected an operative intervention for radiographic lesions confined to enamel.

CONCLUSIONS

A review of current dental literature does not support this approach because a large proportion of proximal tooth surfaces that have associated radiolucencies confined to enamel are not cavitated. This study supports the need for continuing education programmes on the management of dental caries; such programmes should follow an evidence-based model.

How then should we die?: California's "Death with Dignity" Act

The cultural significance of recent changes in medicine and advances in biotechnology can hardly be overstated. Such have stirred fresh interest in the moral foundations of ethical decision-making and lively debate has ensued as well over the basis of human dignity. Largely divorced from the distinctive moral and ethical commitments that once informed and directed medical practice, modern secular notions of bioethics collapse frequently into human philosophical models of rights and justice. The project of Western medicine now continues within the cultural framework of a radical postmodern agenda that calls for the critical deconstruction and absolute relativizing of all knowledge, and the thorough secularization of the public square. Truth, once understood as a fixed expression of a fundamental reality, has been eschewed in favor of personal preference, subjective experience, private interpretation, and radical perspectivism. Perhaps the greatest challenge facing contemporary culture is that of arriving at a clear and convincing consensus on what constitutes moral surety as well as agreement on what knowledge can serve as an adequate foundation for living the moral life. Having abandoned the reality of divine involvement in the creation and sustenance of human life, contemporary culture now toys with what it means to be human without God. Increasingly popular is the view that whether one possesses dignity or not turns on the question of suffering. Under modern parlance it is simply undignified to suffer. Suffering, somehow, is believed to reduce a person to a state that is incompatible with dignity. Therefore, it should come as no surprise that one of the most pressing social issues today involves the effort to legalize physician-assisted suicide--a project based upon the view that people ought to "die with dignity." In California this view is embodied in Assembly Bill 1592, The "Death with Dignity Act." It is intended to establish California as the second state in the United States to legalize physician-assisted suicide. Patterned closely after Oregon's groundbreaking law, the California bill provides for a terminally ill patient to end his or her own life when certain conditions exist. The purpose of this paper is to review the historical development of California Assembly Bill 1592. An evaluation of both the content of this bill and the process by which it was introduced to the California State Assembly will be offered. The student of bioethics will here find that the usual arguments in support of physician-assisted suicide in the United States, as well as euthanasia in the Netherlands, have been employed in support of AB1592; namely suffering and autonomy. Given the rather predictable pattern of argument advanced by advocates of physician-assisted suicide and euthanasia, this discussion will prove useful for those who wish to offer an informed and sensitive Christian response to similar legislative efforts in other states and countries.

What can we do about long-term sequelae of traumatic brain injury?

It is wrong to think that the needs of persons with brain injury are met or complete in the first few months--or even the first few years--after injury. Some persons with TBI may recover in the acute and out-patient care setting sufficiently to return to home, school, or job, but there is a large group who can greatly benefit from extended care. Extended care can take the form of day activity programs, or respite care for caregivers and injured persons, or supported employment, or home-based services, or long-term residential care. The Commission on Accreditation of Rehabilitation Facilities has recently established standards of care for "assisted living" to provide guidelines for agencies providing long-term care for persons with various disabilities, including TBI. It is my strong opinion that private and government-based providers must work hand-in-hand to develop and maintain quality, long-term living options for persons with TBI. Such a collaboration, if sustained, would almost certainly give persons with brain injury and their families a much better chance of returning to pre-injury lifestyle or other preferred options.

Dental needs of elderly hostel residents in inner Melbourne

BACKGROUND

The purpose of this study was to determine the oral health status and treatment needs of elderly hostel residents in Melbourne.

METHOD

One hundred and seventy-five subjects aged 65+ were selected from 20 hostels within a 10 km radius of Melbourne's central business district.

RESULTS

Subjects were clinically examined and interviewed using a standard questionnaire. In the course of the clinical examination, coronal caries, root caries, periodontal disease, denture status and related treatment needs were assessed. The mean age of the subjects was 83.7, the majority of whom were female (80 per cent). About 35 per cent of the sample were dentate. The mean number of teeth present among dentate persons was 13.8, the mean coronal caries experience was 24.9 DMFT and mean root caries was 2.3 R-DF. Of the dentate subjects, 46 per cent required at least one restoration for coronal caries and 30 per cent required at least one restoration for root caries. Most dentate subjects had calculus and none had deep pockets, therefore, indications for periodontal treatment did not include complex care. More than 50 per cent of lower full dentures were retained unsatisfactorily and about half of the total number of subjects required prosthetic treatment.

CONCLUSIONS

Although there was a high number of treatment needs, most requirements involved simple technologies that could be delivered by auxiliaries.