Using non-participant observation to uncover mechanisms: insights from a realist evaluation

This article outlines how a realist evaluation of dementia care in hospitals used non-participant observation to support the refinement and testing of mechanisms likely to lead to the use of person-centred care. We found that comments and explanations of their actions from hospital staff during observation periods provided insights into the reasoning that generated their actions for care in real time. This informed subsequent data collection and analysis. Two worked examples of mechanisms first identified during non-participant observation demonstrate (1) how they were uncovered, and (2) how this informed research activities for theory refinement. Early, iterative engagement with the analytic process, primarily involving reflection and debate with the research team, maximised the potential of observation data to support surfacing underlying mechanisms, linking them to specific contexts and outcomes.Peer reviewedFinal Accepted Versio

Population Variation In and Selection For Resistance to Pyrethroid-Neonicotinoid Insecticides in the Bed Bug

Pyrethroid resistance in bed bugs, Cimex lectularius, has prompted a change to combination products that include a pyrethroid and a neonicotinoid. Ten populations of bed bugs were challenged with two combination products (Temprid SC and Transport GHP). Susceptibility of these populations varied, with the correlated response of the two products indicating cross resistance. We imposed selection on three populations using label rate Temprid, and then reared progeny from unselected and selected strains. All selected strains were significantly less susceptible to Temprid SC than unselected strains. Temprid selected strains were also less susceptible to Transport. The pyrethroid component of Temprid showed a significantly higher LD50 in selected strains, but susceptibility to the neonicotinoid remained unchanged. Taken together these results indicate resistance to combination insecticides is present in field populations at levels that should be of concern, and that short-term selection affecting existing variance in susceptibility can quickly increase resistance

Urinary phthalate metabolite concentrations and blood glucose levels during pregnancy

Purpose: To examine associations between phthalate metabolite urinary concentrations during early pregnancy and blood glucose levels obtained at the time of screening for gestational diabetes mellitus (GDM). Methods: Upon initiation of prenatal care, women with a mean gestational age of 12.8 weeks were recruited for a study of environmental chemical exposures (n = 110) and provided a spot urinary specimen. Blood glucose concentrations (mg/dl) were obtained from the electronic medical record for those patients who did not experience a pregnancy loss and did not transfer care to another facility prior to glucose screening (n = 72). Urinary concentrations of nine phthalate metabolites and creatinine were measured at the US Centers for Disease Control and Prevention. Associations between tertiles of phthalate metabolites concentrations and blood glucose levels were estimated using linear regression. Results: Compared to pregnant women in the lowest concentration tertile, women with the highest urinary concentrations (≥ 3 rd tertile) of mono-iso-butyl phthalate (tertile: ≥ 15.3 μg/l, β = -18.3, 95% CI: -35.4, -1.2) and monobenzyl phthalate (tertile: ≥ 30.3 μg/l, β = -17.3, 95% CI: -34.1, -0.4) had lower blood glucose levels at the time of GDM screening after adjustment for urinary creatinine and demographic covariates. Conclusion: Because maternal glucose levels increase during pregnancy to provide adequate nutrition for fetal growth and development, these findings may have implications for fetal health. However, given the limitations of our study, findings should be interpreted cautiously

Inclusion of Wheat Dried Distillers’ Grains with Solubles from Bioethanol Plants in Diets for Dairy Cows

Dried distillers’ grains with solubles (DDGS) from bioethanol production can replace soya in diets for dairy cows, but optimum inclusion level of European wheat-DDGS (wDDGS) is unknown. Two batches of wDDGS from different UK bioethanol plants were fed to 44 (Experiment 1) and 40 (Experiment 2) cows in a Latin square design. Each wDDGS replaced soya and rapeseed at four inclusion levels (g/kg of diet dry matter (DM): 0, 80, 160 and 240 – Experiment 1; 0, 75, 150 and 225 – Experiment 2). Diets were balanced for metabolisable energy (ME) and protein (MP), and for minimum starch and saturated fat in Experiment 2. In Experiment 1, DM intake (29 kg/d) and milk yield (42.3 kg/d) were unaffected by wDDGS inclusion up to 160 g/kg but were lower than control with 240 g/kg inclusion, which was attributed to low proportion of solubles in this wDDGS batch. In Experiment 2, DM intake (22.4 kg/d) and milk yield (32.1 kg/d) were unaffected by wDDGS inclusion up to 225 g/kg. ME content of wDDGS, determined in vivo, (MJ/kg DM) was 12.1 (Experiment 1) and 13.4 (Experiment 2). It is concluded that optimum inclusion level of wDDGS is at least 225 g/kg DM in diets balanced for minimum starch and saturated fat as well as ME and MP supplies

Is bisphenol-A exposure during pregnancy associated with blood glucose levels or diagnosis of gestational diabetes?

Recent epidemiological studies indicate bisphenol A (BPA), an estrogenic chemical used in production of epoxy, polycarbonate, and plastic may increase risk of insulin resistance and type 2 diabetes. Exposure to BPA during pregnancy may contribute to development of gestational diabetes mellitus (GDM), a precursor to type 2 diabetes in women. This pilot study examined the association between BPA exposure, fasting blood glucose levels (FBG), and GDM diagnosis during pregnancy. Banked urine samples from 22 cases of GDM and 72 controls were analyzed for total (free BPA + conjugates) urinary BPA concentrations (μg/L). FBG levels (mg/dl) were obtained from 1-h 50-g glucose tolerance tests (GTT) that women underwent for routine GDM screening (mean gestational age = 26.6 weeks, SD = 3.8). Those with an initial screening value ≥ 135 mg/dl underwent 3-h 100 g oral GTT. GDM diagnoses were made when the initial screening value was ≥ 200 mg/dl or when values at ≥ 2 time points exceeded 3-h oral GTT thresholds. Among controls, median FBG levels (mg/dL) did not differ across exposure tertiles, defined according to the distribution of total specific-gravity-adjusted urinary BPA concentrations. Logistic regression models controlling for race/ethnicity did not provide evidence of association between BPA exposure and case status across increasing tertiles of BPA exposure (number of GDM cases/controls in tertile1: 13/24; in tertile 2: 6/24; in tertile 3: 3/24). Findings do not support a relationship between total urinary BPA concentrations and altered glucose metabolism during pregnancy. However, due to study limitations, findings need to be interpreted with caution

Evaluation of rumen protected rapeseed expeller (NovaPro) as an alternative to soya bean meal in dairy cow diets

There are environmental, social and economic pressures to reduce the use of soya bean meal in ruminant diets by using alternative protein sources, such as those derived from rapeseed. A new protected form of rapeseed (NovaPro) has been developed to provide similar quantities of digestible undegradable protein (DUP) compared to soya bean meal. NovaPro is hot pressed expelled rapeseed (no hexane solvent used), treated with a specific wood derived xylose-rich lignosulphonate in the presence of elevated moisture and heat to increase DUP. The objective of this study was to evaluate NovaPro as a protein supplement for high yielding dairy cows. Four diets were formulated to supply similar quantities of metabolisable energy and protein but containing different dominant protein sources. The main protein sources were: Control – soya bean and rapeseed meals; NP1 – NovaPro and wheat distillers dried grains with solubles (DDGS); PR – protected solvent-extracted rapeseed meal and wheat-DDGS; NP2 - NovaPro and SoyPass. Diets were fed to 44 cows using a Latin square design with four feeding periods of 28 days each.Milk yield was significantly higher when cows were fed on rapeseed treatment diets (mean 42.7 kg/d) than when fed on the control diet (mean 41.1 kg/d), as was energy-corrected milk (ECM) yield (mean 43.2 versus 41.7kg/d). Dry matter intake was higher when cows were fed on NP1 and NP2 (mean 25.0 kg/d) than when they were fed on the control diet (mean 23.9 kg/d); dry matter intake for PR was intermediate (mean 24.4 kg/d). Concentrations of milk fat and protein reflected differences in milk yield, and there was no difference between treatments in fat or protein yield, although fat plus protein yield was higher when cows were fed on rapeseed treatment diets (mean 2.84 kg/d) than when fed on the control diet (mean 2.72 kg/d). Differences in rumen fluid and blood composition were commensurate with differences in diet composition, nutrient intake and milk yield. Retrospective calculation of metabolisable energy and protein supplies showed that these were within 3% of requirements for observed responses. Calculation of amino acid profiles suggested that profiles, particularly methionine, were better for the rapeseed treatment diets. Results of this study support the hypothesis that cows fed on NovaPro and other rumen protected rapeseed proteins will have similar or improved milk production compared to a control (soya-based) diet. Improved milk yield was accompanied by increased dry matter intake, but it is likely that intake was driven by milk yield rather than vice versa. The most likely explanation for improved milk yield when cows were fed on the rapeseed treatment diets is that amino acid balance was improved compared to control

Circulating B cells in type 1 diabetics exhibit fewer maturation-associated phenotypes

Although autoantibodies have been used for decades as diagnostic and prognostic markers in type 1 diabetes (T1D), further analysis of developmental abnormalities in B cells could reveal tolerance checkpoint defects that could improve individualized therapy. To evaluate B cell developmental progression in T1D, immunophenotyping was used to classify circulating B cells into transitional, mature naïve, mature activated, and resting memory subsets. Then each subset was analyzed for the expression of additional maturation-associated markers. While the frequencies of B cell subsets did not differ significantly between patients and controls, some T1D subjects exhibited reduced proportions of B cells that expressed transmembrane activator and CAML interactor (TACI) and Fas receptor (FasR). Furthermore, some T1D subjects had B cell subsets with lower frequencies of class switching. These results suggest circulating B cells exhibit variable maturation phenotypes in T1D. These phenotypic variations may correlate with differences in B cell selection in individual T1D patients

The impact of teach-back on comprehension of discharge instructions and satisfaction among emergency patients with limited health literacy: A randomized, controlled study

OBJECTIVE: Recommended as a ‘universal precaution’ for improving provider–patient communication, teach-back has a limited evidence base. Discharge from the emergency department (ED) to home is an important high-risk transition of care with potential for miscommunication of critical information. We examined whether teach-back improves: comprehension and perceived comprehension of discharge instructions and satisfaction among patients with limited health literacy (LHL) in the ED. METHODS: We performed a randomized, controlled study among adult patients with LHL, to teach-back or standard discharge instructions. Patients completed an audio-recorded structured interview evaluating comprehension and perceived comprehension of (1) diagnosis, (2) ED course, (3) post-ED care, and (4) reasons to return and satisfaction using four Consumer Assessment of Healthcare Providers and Systems questions. Concordance with the medical record was rated using a five-level scale. We analyzed differences between groups using multivariable ordinal logistic regression. RESULTS: Patients randomized to receive teach-back had higher comprehension of post-ED care areas: post-ED medication (P < 0.02), self-care (P < 0.03), and follow-up instructions (P < 0.0001), but no change in patient satisfaction or perceived comprehension. CONCLUSION: Teach-back appears to improve comprehension of post-ED care instructions but not satisfaction or perceived comprehension. Our data from a randomized, controlled study support the effectiveness of teach-back in a busy clinical setting. Further research is needed to test the utility and feasibility of teach-back for routine use including its impacts on distal outcomes

Assessing urinary phenol and paraben mixtures in pregnant women with and without gestational diabetes mellitus: a case-control study

Prior studies have identified the associations between environmental phenol and paraben exposures and increased risk of gestational diabetes mellitus (GDM), but no study addressed these exposures as mixtures. As methods have emerged to better assess exposures to multiple chemicals, our study aimed to apply Bayesian kernel machine regression (BKMR) to evaluate the association between phenol and paraben mixtures and GDM. This study included 64 GDM cases and 237 obstetric patient controls from the University of Oklahoma Medical Center. Mid-pregnancy spot urine samples were collected to quantify concentrations of bisphenol A (BPA), benzophenone-3, triclosan, 2,4-dichlorophenol, 2,5-dichlorophenol, butylparaben, methylparaben, and propylparaben. Multivariable logistic regression was used to evaluate the associations between individual chemical biomarkers and GDM while controlling for confounding. We used probit implementation of BKMR with hierarchical variable selection to estimate the mean difference in GDM probability for each component of the phenol and paraben mixtures while controlling for the correlation among the chemical biomarkers. When analyzing individual chemicals using logistic regression, benzophenone-3 was positively associated with GDM [adjusted odds ratio (aOR) per interquartile range (IQR) = 1.54, 95% confidence interval (CI) 1.15, 2.08], while BPA was negatively associated with GDM (aOR 0.61, 95% CI 0.37, 0.99). In probit-BKMR analysis, an increase in z-score transformed log urinary concentrations of benzophenone-3 from the 10th to 90th percentile was associated with an increase in the estimated difference in the probability of GDM (0.67, 95% Credible Interval 0.04, 1.30), holding other chemicals fixed at their medians. No associations were identified between other chemical biomarkers and GDM in the BKMR analyses. We observed that the association of BPA and GDM was attenuated when accounting for correlated phenols and parabens, suggesting the importance of addressing chemical mixtures in perinatal environmental exposure studies. Additional prospective investigations will increase the understanding of the relationship between benzophenone-3 exposure and GDM development

Urinary total arsenic and arsenic methylation capacity in pregnancy and gestational diabetes mellitus: A case-control study

Previous studies suggest arsenic exposure may increase the risk of gestational diabetes mellitus (GDM). However, prior assessments of total arsenic concentrations have not distinguished between toxic and nontoxic species. Our study aimed to investigate the relationships between inorganic arsenic exposure, arsenic methylation capacity, and GDM. Sixty-four cases of GDM and 237 controls were analyzed for urinary concentrations of inorganic arsenic species and their metabolites (arsenite (As3), arsenate (As5), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)), and organic forms of arsenic. Inorganic arsenic exposure was defined as the sum of inorganic and methylated arsenic species (iSumAs). Methylation capacity indices were calculated as the percentage of inorganic arsenic species [iAs% = (As3 + As5)/iSumAs, MMA% = MMA/iSumAs, and DMA% = DMA/iSumAs]. Multivariable logistic regression was performed to evaluate the association between inorganic arsenic exposure, methylation capacity indices, and GDM. We did not observe evidence of a positive association between iSumAs and GDM. However, women with GDM had an increased odds of inefficient methylation capacity when comparing the highest and lowest tertiles of iAs% (adjusted odds ratio (aOR) = 1.48, 95% CI 0.58–3.77) and MMA% (aOR = 1.95 (95% CI 0.81–4.70) and a reduced odds of efficient methylation capacity as indicated by DMA% (aOR = 0.62 (95% CI 0.25–1.52), though the confidence intervals included the null value. While the observed associations with arsenic methylation indices were imprecise and warrant cautious interpretation, the direction and magnitude of the relative measures reflected a pattern of lower detoxification of inorganic arsenic exposures among women with GDM