Per- and polyfluoroalkyl substances exposure science: current knowledge, information needs, future directions

BACKGROUND

Per- and polyfluoroalkyl substances have been documented at all spatial scales with concerns of adverse ecological and human health effects. Human exposures and relative pathway contributions depend on the specific population, their exposure scenarios, and pathways of local sources.

OBJECTIVES

Provide a narrative overview of (1) current per- and polyfluoroalkyl substances knowledge for sources, concentrations, and exposures; (2) critical per- and polyfluoroalkyl substances exposure information gaps and needs, and (3) United States Environmental Protection Agency's strategies and action plans in collaboration with other federal, industrial, and academic partners.

METHODS

A literature review was conducted for per- and polyfluoroalkyl substances (primarily perfluorooctane sulfonate and perfluorooctanoic acid) compounds in blood, water, soil, house dust, indoor and outdoor air, consumer products, food, and fish, as well as per- and polyfluoroalkyl substances exposure modeling.

RESULTS

Large variability exists in measured per- and polyfluoroalkyl substances environmental concentrations and human exposures. Literature indicated that ingestion of food ("background"), drinking water ("contaminated" scenarios), and house dust (for children) are main pathways for perfluorooctane sulfonate and perfluorooctanoic acid.

DISCUSSION

Needs for addressing critical data gaps are identified. More information is available on long-chain per- and polyfluoroalkyl substances than for replacement and emerging compounds. A large-scale research effort by the United States Environmental Protection Agency and other federal agencies is underway for a better understanding of per- and polyfluoroalkyl substances exposures.

Using technology and cross-cultural teams to deliver trauma-informed medication management

Issue/Problem

Cambodian Americans have high rates of mental health conditions, diabetes and cardiovascular disease. Unique risk factors include history of malnutrition, torture, social isolation, and poor social determinants of health. Community CARES is a trauma-informed model applicable to any trauma community with complex chronic health and mental health problems.

Description of the problem

High-touch, high-tech approaches can improve access to culturally and linguistically appropriate medication therapy management (MTM) services. Over 12 months, pharmacists teamed with community health workers (CHWs) to provide MTM services in Connecticut and California. Face-to-face consultations occurred in Connecticut, while patients and CHWs in California used teleconferencing with the pharmacist in Connecticut. Project goals: improve drug therapy outcomes, reduce inappropriate medication use, improve medication adherence, display cost savings.

Results

96 patients, average age 69, completed the project. Patients averaged 6.6 medical conditions and 10.3 medications. Pharmacists identified 604 medication-related problems, resolving 93%. Drug therapy outcomes increased 35%, medication adherence improved 23%, inappropriate medication use decreased 35%, and depression screening scores improved 25%. Return on investment ratio was 6:1, a savings of $3032/patient/year. Health improvements from face-to-face and telehealth MTM consultations were similar.

Lessons

Healthcare workforce is optimized by linking CHWs with pharmacists and technology to deliver cost-effective MTM services. The approach is generalizable to populations challenged by distance, disability, language, or culture. Public health care policies need to reflect team approaches and value-based payment models.

Main messages: The virtual cross-cultural team MTM model for underserved populations has the potential to meet the triple aim goals of better care, better health, and lower costs in multiple settings.

Key messages

Virtual cross-cultural team MTM model for underserved populations. Meets the triple aim goals of better care, better health, and lower costs in multiple settings.

Multi-drug resistant Escherichia coli in diarrhoeagenic foals: Pulsotyping, phylotyping, serotyping, antibiotic resistance and virulence profiling

Extraintestinal pathogenic E. coli (ExPEC) possess the ability to cause extraintestinal infections such as urinary tract infections, neonatal meningitis and sepsis. While information is readily available describing pathogenic E. coli populations in food-producing animals, studies in companion/sports animals such as horses are limited. In addition, many antimicrobial agents used in the treatment of equine infections are also utilised in human medicine, potentially contributing to the spread of antibiotic resistance determinants among pathogenic strains. The aim of this study was to phenotypically and genotypically characterise the multidrug resistance and virulence associated with 83 equine E. coli isolates recovered from foals with diarrhoeal disease. Serotyping was performed by both PCR and sequencing. Antibiotic resistance was assessed by disc diffusion. Phylogenetic groups, virulence genes, antibiotic resistance genes and integrons were determined by PCR. Thirty-nine (46%) of the isolates were classified as ExPEC and hence considered to be potentially pathogenic to humans and animals. Identified serogroups O1, O19a, O40, O101 and O153 are among previously reported human clinical ExPEC isolates. Over a quarter of the E. coli were assigned to pathogenic phylogroups B2 (6%) and D (23%). Class 1 and class 2 integrons were detected in 85% of E. coli, revealing their potential to transfer MDR to other pathogenic and non-pathogenic bacteria. With 65% of potentially pathogenic isolates harbouring one or more TEM, SHV and CTX-M-2 group β-lactamases, in addition to the high levels of resistance to fluoroquinolones observed, our findings signal the need for increased attention to companion/sport animal reservoirs as public health threats.

The Effect of Education and Counselling on Knowledge, Attitudes and Beliefs about Responses to Acute Myocardial Infarction Symptoms

The time that elapses from the onset of symptoms of acute myocardial infarction (AMI) to treatment has a significant effect on mortality and morbidity. This study reports the effectiveness of an education and counselling intervention on knowledge, attitudes and beliefs about AMI symptoms and the appropriate response to symptoms. The intervention was tested in a randomised controlled trial of 200 people with a history of coronary heart disease (CHD). The groups were equivalent at baseline on study outcomes, clinical history and sociodemographic characteristics with the exception of more women in the intervention group (38% vs. 24%). The results of repeated measures ANOVA showed that the intervention resulted in improved knowledge of CHD, AMI symptoms and the appropriate response to symptoms that was sustained to 12 months (p=0.02). There were no differences between groups' attitudes and beliefs over time. It is concluded that a short individual teaching and counselling intervention resulted in improved knowledge of CHD, AMI symptoms and the appropriate response to symptoms in people at risk of AMI sustained to 12 months.

Eutectic mixture of local anaesthetics (EMLA) 5% cream as a primary dressing on a painful lower leg ulcer

Patients living with chronic leg ulceration may frequently experience moderate to severe wound-related pain, which may not be alleviated by oral analgesics alone. Poorly controlled leg ulcer pain can prevent timely and effective wound management strategies being implemented, and increase wound healing times. Furthermore, patients with poorly controlled leg ulcer pain can experience continuous pain, which significantly affects quality of life. This case report introduces an innovative way of using the eutectic mixture of local anaesthetics (EMLA) 5% cream to reduce wound-related pain, reduce oral analgesic intake, and improve health-related quality of life for a patient with a painful, chronic lower leg ulcer.

Rapid and sensitive detection of Pseudomonas aeruginosa in chlorinated water and aerosols targeting gyrB gene using real-time PCR

AIMS

For the rapid detection of Pseudomonas aeruginosa from chlorinated water and aerosols, gyrB gene-based real-time PCR assay was developed and investigated.

METHODS AND RESULTS

Two novel primer sets (pa722F/746MGB/899R and pa722F/746MGB/788R) were designed using the most updated 611 Pseudomonas and 748 other bacterial gyrB genes for achieving high specificity. Their specificity showed 100% accuracy when tested with various strains including clinical isolates from cystic fibrosis patients. The assay was tested with Ps. aeruginosa-containing chlorinated water and aerosols to simulate the waterborne and airborne transmission routes (detection limit 3·3 × 10² CFU per PCR-2·3 × 10³ CFU per PCR). No chlorine interference in real-time PCR was observed at drinking water level (c. 1 mg l⁻¹), but high level of chorine (12 mg l⁻¹) interfered the assay, and thus neutralization was needed. Pseudomonas aeruginosa in aerosol was successfully detected after capturing with gelatin filters with minimum 2 min of sampling time when the initial concentration of 10⁴ CFU ml⁻¹ bacteria existed in the nebulizer.

CONCLUSIONS

A highly specific and rapid assay (2-3 h) was developed by targeting gyrB gene for the detection of Ps. aeruginosa in chlorinated water and aerosols, combined with optimized sample collection methods and sample processing, so the direct DNA extraction from either water or aerosol was possible while achieving the desired sensitivity of the method.

SIGNIFICANCE AND IMPACT OF THE STUDY

  The new assay can provide timely and accurate risk assessment to prevent Ps. aeruginosa exposure from water and aerosol, resulting in reduced disease burden, especially among immune-compromised and susceptible individuals. This approach can be easily utilized as a platform technology for the detection of other types of micro-organisms, especially for those that are transmitted via water and aerosol routes, such as Legionella pneumophila.

A brief metacognition questionnaire for the elderly: comparison with cognitive performance and informant ratings the Cache County Study

OBJECTIVE

To examine the utility of a brief, metacognition questionnaire by examining its association with objective cognitive testing and informant ratings. We hypothesized that the association between self-ratings of change and both outcomes would be greater among individuals without dementia than among those with dementia.

METHODS

Participants were 535 persons without dementia and 152 with dementia from the Cache County Memory Study who had completed a metacognition questionnaire, two administrations of the Modified Mini-Mental State Exam (3 MS) and who had data on the Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE). Cronbach's alpha was calculated as a measure of internal consistency of the metacognition questionnaire. Multiple regression was used to examine the relationship between metacognition and 3 MS change. Logistic regression was used to examine the relationship between metacognition and IQCODE ratings (no change vs. worse).

RESULTS

Cronbach's alpha was 0.75. Among individuals without dementia, metacognition significantly predicted 3 MS change (p = .027) and IQCODE ratings (OR = 4.0, 95% CI = 1.2-13.8, p = .029), suggesting consistency among measures. For those with dementia, there was a weak, inverse relationship between 3 MS change and metacognition (r = -0.16, p = .056). IQCODE ratings were not significantly associated with metacognition (p = .729). Degree of dementia severity did not modify the relationship between metacognition and either outcome (p > .05).

CONCLUSIONS

We demonstrated adequate internal consistency and evidence for validity of a brief metacognition questionnaire. The questionnaire may provide a useful adjunct to memory and functional assessments for assessing anosognosia in elderly populations.

Prospective study of early bereavement on psychological and behavioural cardiac risk factors

BACKGROUND

Increasing evidence supports the role of emotional stress in the onset of cardiovascular disease. Although bereavement is a major emotional stress with both acute and more long-term features, the mechanism of its association with cardiovascular risk is not well understood, in particular because of limited studies of acute bereavement. The aim of the study was to identify psychological and behavioural changes in acute bereavement and potential modifiers of these changes.

METHODS

Bereaved (n= 62) and non-bereaved individuals (n= 50) were evaluated within 2 weeks and at 6 months following loss using the Centre for Epidemiologic Studies -- Depression, Spielberger State Anxiety and Anger, Social Support Questionnaire and changes in appetite, cigarette and alcohol consumption, cortisol and lipids.

RESULTS

Compared with non-bereaved, acutely bereaved had increased symptoms of depression (26.7 +/- 1.7 vs 5.9 +/- 0.7, P < 0.001), anxiety (47.4 +/- 2.0 vs 28.2 +/- 1.4, P < 0.001) and anger (median 16.0 vs 15.0, P < 0.001). Greater depressive symptoms were associated with being unprepared for the death, decreased sleep duration and younger age. Acutely, bereaved slept less than non-bereaved (5.8 +/- 0.2 vs 7.2 +/- 0.2 h, P < 0.001). Reduced sleep time was associated with increased anger and depression and decreased satisfaction with social support. Compared with the non-bereaved, the acutely bereaved had higher cortisol (median 306 vs 266, P= 0.003), reduced appetite (P < 0.001) and lower total cholesterol (median 4.9 vs 5.4, P= 0.006) and low-density lipoprotein (median 2.4 vs 2.9, P < 0.001).

CONCLUSION

These results offer insight into the psychological, behavioural and physical changes that may contribute to cardiovascular risk in bereavement.

Comparison of concentrations of Rhodococcus equiand virulent R. equi in air of stables and paddocks on horse breeding farms in a temperate climate

REASONS FOR PERFORMING STUDY

Rhodococcoccus equi is a significant cause of bronchopneumonia in foals worldwide. Infection of the lungs is believed to result from inhalation of virulent R. equi in dust from contaminated environments. A measure of infectious risk in an environment is the level of airborne contamination.

OBJECTIVES

To assess and compare the level of airborne virulent R. equi in paddocks and stables.

METHODS

Air samples were collected sequentially over the 2003 foaling season from the paddocks and stables on 3 Irish horse breeding farms affected by R. equi pneumonia. Colony blotting and DNA hybridisation techniques allowed quantitation of virulent R. equi.

RESULTS

The odds of detecting airborne virulent R. equi in stables were 173 times greater than in paddocks. The median airborne concentration of virulent R. equi was significantly higher (P < 0.001) in stables than in paddocks on all farms. These observations suggested that stables were high-risk areas for infection.

CONCLUSIONS AND POTENTIAL RELEVANCE

Our results indicate that contaminated stables are a significant risk factor in the epidemiology of R. equi pneumonia on horse-breeding farms in a temperate climate, such as in Ireland. Management strategies that improve the air hygiene of stables, through better ventilation, use of less fragile bedding material and the use of fogging agents to reduce the airborne concentration of virulent R. equi, may reduce the incidence and severity of R. equi pneumonia on farms.

Molecular epidemiology of clinical isolates of Pseudomonas aeruginosa isolated from horses in Ireland

Clinical isolates (n = 63) of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes) showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E) accounting for 10/63 (15.9%) of the isolates. ERIC2 RAPD PCR proved to be a highly discriminatory molecular typing tool of P. aeruginosa in isolates recovered from horses. With the adoption of several controls to aid reproducibility, this technique may be useful as an alternative to PFGE, particularly in epidemiological investigations of outbreaks where speed may be a significant parameter. This is the first report of clonal heterogeneity amongst P. aeruginosa from horses and demonstrated that ERIC RAPD PCR is a rapid method for the examination of this species in horses, which may be useful in outbreak analysis.

Resistance studies of erythromycin and rifampin for Rhodococcus equi over a 10-year period

This study sought to determine whether an increase in resistance of Rhodococcus equi to the antibiotics rifampin and erythromycin occurred over a 10-year period. This was carried out by the use of E test strips for rifampin and erythromycin to determine the MIC (minimum inhibitory concentration) values of Rhodococcus equi to this combination of antibiotics.The findings of this study indicated that there was an increase in resistance of Rhodococcus equi to rifampin and erythromycin over the 10-year period. The MIC for rifampin increased from 0.081 μg/ml in 1996 to 0.187 μg/ml in 2006 and from 0.258 μg/ml for erythromycin during the years prior to 2000 to 0.583 μg/ml in 2006.This finding suggests that there may be a problem in the treatment of Rhodococcus equi infections in foals in the future, particularly as the number of drugs available for treatment of Rhodococcus equi infection is limited because of the intracellular capabilities of this bacterium. Antibiotics used in its treatment have to be able to penetrate the polysaccharide cell wall of Rhodococcus equi as well as the alveolar macrophages in which the bacterium is capable of surviving.

Rhodococcus equi infection in foals: the science of 'rattles'

Infection with Rhodococcus (Corynebacterium) equi is a well-recognised condition in foals that represents a consistent and serious risk worldwide. The condition manifests itself primarily as one of pulmonary abscessation and bronchitis, hence the terminology of 'rattles' derived from its most obvious clinical sign, frequently terminal when first identified. This review addresses the clinical manifestation, bacteriology and pathogenesis of the condition together with recent developments providing knowledge of the organism in terms of virulence, epidemiology, transmission and immune responses. Enhanced understanding of R. equi virulence mechanisms and biology derived from the recently available genome sequence may facilitate the rational development of a vaccine and the improvement of farm management practices used to control R. equi on stud farms in the future. Reliance on vaccines alone, in the absence of management strategies to control the on-farm challenge is likely to be disappointing.

Trends in antimicrobial susceptibility among isolates of Campylobacter species in Ireland and the emergence of resistance to ciprofloxacin

Measurements were made of the susceptibility to six commonly prescribed antibiotics, including erythromycin, tetracycline and ciprofloxacin, of 130 isolates of Campylobacterjejuni and 15 isolates of Campylobacter coli cultured from human and poultry sources during 2000. The results were compared with the results from a collection of strains isolated between 1996 and 1998. The levels of resistance to erythromycin remained low, 2 per cent and 4.4 per cent for the human and poultry isolates, respectively. Resistance to tetracycline had increased to 31 per cent and 24.4 per cent from 13.9 per cent and 18.8 per cent for the human and poultry isolates, respectively. However, the resistance to ciprofloxacin of the strains isolated during 2000 had increased to 30 per cent, whereas between 1996 and 1998 there had been no resistance to this agent among human isolates, and only 3.1 per cent resistance among poultry isolates. The molecular basis for this resistance has been shown to be the result of a single amino acid substitution, Thr-86-Ile, in the gyrA subunit of DNA gyrase in Cjejuni. A subset of 59 isolates was tested by molecular methods and all of the 25 phenotypically resistant isolates possessed this substitution. None of the human isolates had been treated with ciprofloxacin before their laboratory isolation.

Prevalence and public health significance of blemishes in cuts of Irish beef

Between February 1999 and February 2000 more than 45,000 quarters of Irish beef cattle were examined for the presence of blemishes as they were cut into primal and subprimal cuts. A total of 2,379 blemishes, either scars or cysts, were found. Eight of the scars and one cyst tested positive for residues of inhibiting substances.

Ethanol and gene expression in brain

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Izuru Matusmoto and Peter A. Wilce. The presentations were (1) GABA receptor subunit expression in the human alcoholic brain, by Tracey Buckley and Peter Dodd; (2) NMDAR gene expression during ethanol addiction, by Jorg Puzke, Rainer Spanagel, Walther Zieglgansberger, and Gerald Wolf; (3) Differentially expressed gene in the nucleus accumbens from ethanol-administered rat, by Shuangying Leng; (4) Expression of a novel gene in the alcoholic brain, by Peter A. Wilce; and (5) Investigations of haplotypes of the dopamine D2-receptor gene in alcoholics, by Hans Rommelspacher, Ulrich Finckh, and Lutz G. Schmidt.

Lack of specificity of trans,trans-muconic acid as a benzene biomarker after ingestion of sorbic acid-preserved foods

The benzene metabolite, trans,trans-muconic acid (MA), has been shown to be a sensitive and specific biomarker for ambient benzene exposure levels as low as approximately 0.5 ppm. However, at lower exposure levels, the use of MA as a benzene biomarker is complicated by the fact that it is also a metabolite of the food preservative, sorbic acid. To better assess the extent of this interference, MA was measured in sequential spot urine samples over a 2-day study period from eight volunteers (four adults and two parent-children pairs) who consumed two sorbic acid-preserved foods. Large increases in MA concentration were seen after ingestion of both foods. Individual peaks ranged as high as 1673.7 ng/ml (705.3 ng/mg creatinine) in adults and 1752.1 ng/mg creatinine (1221.3 ng/ml) in children. Ratios of peak to baseline values varied from 2.5 to 60. The average peak in the seven subjects who showed an increase in MA after ingestion of the first sorbic acid-containing food was 531.1 ng/ml (693.2 ng/mg creatinine). The average in the seven participants who ingested the second food was 1102.1 ng/ml (795.3 ng/mg creatinine). Twenty-four-hour personal air benzene levels were all low (< or = 5.6 ppb). Substantial variation in MA results were seen in some males related to creatinine adjustment. These data indicate that sorbic acid-preserved foods have the potential to cause substantial interference with MA as a biomarker for both occupational and environmental benzene exposure in populations, such as in the United States, where consumption of preserved foods is common. Development of methods to minimize and/or assess sorbic acid interference will improve MA specificity in such populations.

The relationship of self-injurious behavior and aggression to social skills in persons with severe and profound learning disability

In this study, we investigated differences in social skills among four groups of individuals with severe and profound learning disabilities. The comparison groups were composed of individuals engaging in self-injurious behavior, aggression, both behaviors, or neither of the behaviors. We measured social skills using the Matson Evaluation of Social Skills for Individuals with Severe Retardation, a standardized assessment of social skills in persons with severe or profound learning disability. The results indicated that individuals displaying maladaptive behaviors exhibited a restricted range of social behaviors compared to controls. Also, group membership based on self-injury and aggression was predicted based on profiles of scores on the Matson Evaluation of Social Skills for Individuals with Severe Retardation. These findings are consistent with reports in other studies that note social skills deficits in aggressive and self-injurious persons with learning disabilities. However, in this case a standardized assessment of these deficits was possible and specific skills problems were identified. Implications of the findings for identification and treatment of self-injury and aggression are discussed.