When it comes to sedentary behaviour modification, should people be told what to do? A randomized comparison trial among home-based office workers living in Ontario, Canada

The effects of adding choice architecture to a theory-based (Health Action Process Approach; HAPA) sedentary intervention remain unknown. To investigate whether choice architecture enhances a theory-based sedentary behaviour reduction intervention in home-based office workers. A 4-week HAPA-based intervention was conducted in London, Canada. Choice architecture was tested as an enhancement via a two (group: 'Choice of Intervention' vs. 'No Choice Intervention') by two (time: Baseline vs. Week 4) factorial repeated measure randomized comparison design. Sedentary behaviour reduction strategies focussed on obtaining a sedentary break frequency (BF) of every 30-45 min with break durations (BD) of 2-3 min. BF, BD, sitting, standing, and moving time were objectively measured (activPAL4™) at both time points. Participants (n = 148) were 44.9 ± 11.4 years old and 72.3% female. BF and total sitting time showed a time effect (P < .001), where both groups improved over the 4 weeks; there were no significant differences between groups across time. BD, standing, and moving time had a significant group by time effect where the 'No Choice' group showed significant increases in BD (P < .001), standing (P = .006), and moving time (P < .001) over the 4 weeks. Augmenting a theory-based intervention with choice architecture resulted in change in some sedentary behaviours in at home office workers. Specifically, while BF increased for all participants, the 'No Choice' group exhibited greater changes for BD, standing, and moving time compared with the 'Choice' group. Overall, these changes exceeded the intervention BF and BD goals.

Stability of and change in substance use risk personality: Gender differences and smoking cigarettes among early adolescents

OBJECTIVE

Adolescents show a steadily increasing inclination toward health risk behaviors, including smoking cigarettes. There is ample evidence that personality traits are related to smoking behavior. However, less is known about the stability of and change in these personality traits during early adolescence and whether smoking behavior affects the developmental trajectories. Moreover, less is known about the influence of gender on the course of personality.

METHOD

Longitudinal data of three waves were used from 1121 early adolescents. To measure personality, the Substance Use Risk Profile Scale was used. Individual growth curve models were conducted to measure the stability, mean-level change and individual differences in change for personality.

RESULTS

Stability of personality was moderate for boys and ranged from moderate to high for girls. On average early adolescents became more impulsive and more sensation seeking over a period of 18 months. Furthermore, hopelessness for girls increased and the increase in sensation seeking was higher for girls than for boys. Third, smoking behavior was related to all personality traits, indicating that smoking adolescents are more anxious, hopeless, impulsive and sensation seeking than non-smoking adolescents.

CONCLUSIONS

Our results are in line with the disruption hypothesis, i.e., during early adolescence there is a dip in personality maturity. There are clear differences between girls and boys in stability of and change in personality traits. Besides, although smoking behavior is related to personality, the change in personality is probably related to other variables.

Validity of the occupational sitting and physical activity questionnaire (OSPAQ) for home-based office workers during the COVID-19 global pandemic: A secondary analysis

High levels of occupational sitting is an emerging health concern. As working from home has become a common practice as a result of COVID-19, it is imperative to validate an appropriate self-report measure to assess sitting in this setting. This secondary analysis study aimed to validate the occupational sitting and physical activity questionnaire (OSPAQ) against an activPAL4™ in full-time home-based 'office' workers (n = 148; mean age = 44.90). Participants completed a modified version of the OSPAQ and wore an activPAL4™ for a full work week. The findings suggest that the modified OSPAQ has fair levels of validity in terms of correlation for sitting and standing (ρ = 0.35-0.43, all p < 0.05) and agreement (bias = 2-12%) at the group level; however, estimates were poor at an individual level, as suggested by wide limits of agreement (±22-30%). Overall, the OSPAQ showed to be an easily administered and valid questionnaire to measure group level sitting and standing in this sample of adults.

Determination of Chlormequat and Mepiquat in Foods by Liquid Chromatography/Mass Spectrometry or Liquid Chromatography/Tandem Mass Spectrometry: Interlaboratory Study

Interlaboratory validation studies have been performed on 2 methods for the determination of chlormequat (CLQ) and mepiquat (MPQ). Both methods used identical extraction procedures and stable isotope internal standardization but differed in the use of liquid chromatography/mass spectrometry (LC/MS) or LC/tandem mass spectrometry (LC/MS/MS) for the determination, the amount of internal standard used, and the expected limit of detection. After addition of deuterated internal standards, CLQ and MPQ were extracted with methanol–water and determined by LC/MS or LC/MS/MS with positive electrospray ionization. Eight European laboratories participated in the LC/MS method study, analyzing mushroom, pear, wheat flour, and fruit puree with residues of CLQ in the range 0.040–1.19 mg/kg and of MPQ in the range 0.041–0.39 mg/kg. For CLQ, the Horwitz ratio (HoRat) values for individual test materials/levels were in the range 0.85–1.13 with amean of 1.00, showing good method performance. For MPQ, the Ho values for mushroom, pear (both levels), and wheat flour were in the range 0.83–0.94, again indicating good method performance. For the determination of MPQ in infant food (fruit puree) at 0.041 mg/kg, the Ho was 1.7 when a value of 0 reported by one participant was excluded. In the LC/MS/MS study, in which 11 laboratories participated, a separate sample set was analyzed with residues of CLQ in the range 0.007–1.03 mg/kg and of MPQ in the range 0.008–0.72 mg/kg. Ho values for CLQ were in the range 0.27–1.36 and for MPQ in the range 0.51–2.10, all corresponding to acceptable method performance.

White matter changes in the perforant path area in patients with amyotrophic lateral sclerosis

OBJECTIVE

The aim of this study was to test the hypothesis that white matter degeneration of the perforant path - as part of the Papez circuit - is a key feature of amyotrophic lateral sclerosis (ALS), even in the absence of frontotemporal dementia (FTD) or deposition of pTDP-43 inclusions in hippocampal granule cells.

METHODS

We used diffusion Magnetic Resonance Imaging (dMRI), polarized light imaging (PLI) and immunohistochemical analysis of post mortem hippocampus specimens from controls (n = 5) and ALS patients (n = 14) to study white matter degeneration in the perforant path.

RESULTS

diffusion Magnetic Resonance Imaging demonstrated a decrease in fractional anisotropy (P = 0.01) and an increase in mean diffusivity (P = 0.01) in the perforant path in ALS compared to controls. PLI-myelin density was lower in ALS (P = 0.05) and correlated with fractional anisotropy (r = 0.52, P = 0.03). These results were confirmed by immunohistochemistry; both myelin (proteolipid protein, P = 0.03) and neurofilaments (SMI-312, P = 0.02) were lower in ALS. Two out of the fourteen ALS cases showed pTDP-43 pathology in the dentate gyrus, but with comparable myelination levels in the perforant path to other ALS cases.

CONCLUSION

We conclude that degeneration of the perforant path occurs in ALS patients and that this may occur before, or independent of, pTDP-43 aggregation in the dentate gyrus of the hippocampus. Future research should focus on correlating the degree of cognitive decline to the amount of white matter atrophy in the perforant path.

Acrylamide exposure from foods of the Dutch population and an assessment of the consequent risks

At the end of April 2002, the Swedish Food Administration reported the presence of acrylamide in heat treated food products. Acrylamide has been shown to be toxic and carcinogenic in animals, and has been classified by the WHO/IARC among others as 'probably carcinogenic for humans'. The purposes of this study were firstly to analyse acrylamide contents of the most important foods contributing to such exposure, secondly, to estimate the acrylamide exposure in a representative sample of the Dutch population, and thirdly to estimate the public health risks of this consumption. We analysed the acrylamide content of foods with an LC-MS-MS method. The results were then used to estimate the acrylamide exposure of consumers who participated in the National Food Consumption Survey (NFCS) in 1998 (n=6250). The exposure was estimated using the probabilistic approach for the total Dutch population and several age groups. For 344 food products, acrylamide amounts ranged from <30 to 3100 microg/kg. Foods with the highest mean acrylamide amounts were potato crisps (1249 microg/kg), chips (deep-fried) (351 microg/kg), cocktail snacks (1060 microg/kg), and gingerbread (890 microg/kg). The mean acrylamide exposure of the NFCS participants was 0.48 microg/kg bw/day. Risk of neurotoxicity is negligible. From exposure estimations it appears that the additional cancer risk might not be negligible.

[The reliability of vaginal cytology in determining the optimal mating time in the bitch]

The reliability of vaginal cytology for determining the optimal mating period is controversial. The importance of the site for obtaining the smear (the vestibule or the vagina) and the best staining method are also unclear. Therefore, we investigated the reliability of vaginal cytology as compared to plasma progesterone concentrations for determining the optimal mating period. Additionally, the influence of different locations for obtaining the smears and of the staining methods, i.e. May-Grünwald-Giemsa or Papanicolaou, a method that stains keratin in superficial cells, was examined. In total, the vaginal cytology of 35 bitches during the follicular phase was examined three times a week, until the optimal time for mating was established, based on plasma progesterone concentrations measured with a 125Iodine radio-immunoassay. The results indicate that vaginal cytology is not useful for determining the optimal mating period in bitches, since mating according to cytological findings would have resulted in only 28% of the bitches being mated at the proper time. The site for obtaining the smear and the staining method did not affect accuracy. It is therefore concluded that cytology is not useful in breeding management to determine the optimal mating period. It can be used, however, to determine the stage of the cycle in general, e.g. the early part of the follicular phase or the metoestrus and the detection of disorders in the follicular phase. For this purpose, a smear from the vestibule, stained with a morphological staining method, provides sufficient information.

Optimization of the postcolumn hydrolysis reaction on solid phases for the routine high-performance liquid chromatographic determination of N-methylcarbamate pesticides in food products

Various solid-phase materials were evaluated as catalysts for the postcolumn hydrolysis of N-methylcarbamate pesticides in a high-performance liquid chromatographic (HPLC) method for food products. Inexpensive magnesium oxide has been used for the first time in HPLC as a very efficient catalyst and as a good alternative for, e.g., expensive anion-exchange resins. The reaction mechanism and kinetics were studied through measurement of the reaction band broadening, which depends on the stationary phase, mobile phase composition and flow-rate, and reaction temperature. Also, relationships between carbamate structure and reactivity were examined. The usefulness of the optimized postcolumn system was thoroughly tested by application to crop sample analysis during an extended period of time. The range of application of the solid-phase reaction was extended to 22 carbamate pesticides and ten of their metabolites. For crop sample analysis, limits of determination in the range 1-10 ppb were obtained.