Physical activity is associated with a low prevalence of musculoskeletal disorders in the Royal Norwegian Navy: a cross sectional study

Background  

Despite considerable knowledge about musculoskeletal disorders (MSD) and physical, psychosocial and individual risk factors there is limited knowledge about physical activity as a factor in preventing MSD. In addition, studies of physical activity are often limited to either leisure activity or physical activity at work. Studies among military personnel on the association between physical activity at work and at leisure and MSD are lacking. This study was conducted to find the prevalence of MSD among personnel in the Royal Norwegian Navy and to assess the association between physical activity at work and at leisure and MSD.     

Use of buccal cells collected in mouthwash as a source of DNA for clinical testing

CONTEXT: To maximize the participation rate in population genetic studies, alternatives to invasive whole blood collection are increasing. One such alternative is buccal epithelial cell collection, which, in contrast to venipuncture and finger sticks, is painless. Buccal cells, if collected and purified efficiently, offer an acceptable source for DNA to be used in research and clinical applications. OBJECTIVE: To develop a noninvasive sampling method for collecting cells for routine DNA testing in a clinical laboratory setting. DESIGN: Five factors were used to evaluate several brands of mouthwash: (1) compatibility with the DNA purification chemistry, (2) DNA yield, (3) DNA quality, (4) DNA stability at room temperature, and (5) mouthwash taste. Next, an optimization study was undertaken to maximize DNA yield. Finally, a validation study was undertaken with the optimized protocol to test a panel of 14 donors for DNA yield and performance and to test for the stability of DNA held in mouthwash. SETTING: Industrial research and development laboratory. RESULTS: Of 5 mouthwashes tested, Scope brand mouthwash received the highest overall ranking. The addition of proteinase K and glycogen to the protocol significantly enhanced DNA yields, with a test panel (n = 14) giving a range of 12 to 60 microg of DNA per donor. In a 4-week room temperature stability study, the DNA in mouthwash samples was found to be stable for at least 2 weeks. CONCLUSION: A clinically validated DNA purification chemistry was adapted to a noninvasive specimen collection method. This method used a commercially available mouthwash, Scope, to collect buccal epithelial cells for the preparation of high-quality DNA in high yield.     

Complications,risk factors,and patients-reported outcomes after skin-sparing mastectomy followed by breast reconstruction in women with BRCA mutations

Background: Women with a BRCA mutation have the option of undergoing prophylactic mastectomy and immediate breast reconstruction; however, the potential negative effects of reconstruction on women’s physical and psychological well-being are unclear. This study aimed to investigate complications, patient-reported pain, health-related quality-of-life (HRQoL) and satisfaction following reconstructive surgery at Oslo University Hospital between 2006 and 2013.

Methods: Data were collected retrospectively from the records of 238 patients. A cross-sectional survey was conducted to collect patient-reported HRQoL and satisfaction with outcome using the Short Form-12 questionnaires and Breast-Q. The self-administered Leeds assessment of neuropathic symptoms and signs was used to assess neuropathic pain.

Results: The majority of participants (89.5%) underwent implant-based breast reconstruction (IBBR); the remainder underwent autologous-tissue breast reconstruction (ATBR). Overall, 28.6% had complications within 30?days of surgery and 14.6% required resurgery because of complications. Women who underwent IBBR had a later onset of complications than those undergoing ATBR. Participants in the survey (n?=?175 of 219, response rate 79.9%) reported similar HRQoL to an age-matched general female population. Few (2.9%) reported neuropathic pain. Patients who underwent IBBR were significantly less satisfied with the reconstructed breast (p?=?.001) and overall outcome (p?=?.02) than those who underwent ATBR, but there were no significant differences in HRQoL scores between the two groups.

Conclusions: Overall, 28.6% of the women had complications within 30?days and 14.6% needed resurgery. Few had neuropathic pain. Women who underwent ATBR were more satisfied with the overall outcome than those who underwent IBBR.     

Dominant ARL3-related retinitis pigmentosa

Purpose: To clinically and genetically characterise a second family with dominant ARL3-related retinitis pigmentosa due to a specific ARL3 missense variant, p.(Tyr90Cys).

Methods: Clinical examination included optical coherence tomography, electroretinography, and ultra-wide field retinal imaging with autofluorescence. Retrospective data were collected from the registry of inherited retinal diseases at Oslo university hospital. DNA was analysed by whole-exome sequencing and Sanger sequencing. The ARL3 missense variant was visualized in a 3D-protein structure.

Results: The phenotype was non-syndromic retinitis pigmentosa with cataract associated with early onset of decreased central vision and central retinal thinning. Sanger sequencing confirmed the presence of a de novo ARL3 missense variant p.(Tyr90Cys) in the index patient and his affected son. We did not find any other cases with rare ARL3 variants in a cohort of 431 patients with retinitis pigmentosa-like disease. By visualizing Tyr90 in the 3D protein structure, it seems to play an important role in packing of the α/β structure of ADP-ribosylation factor-like 3 (ARL3). When changing Tyr90 to cysteine, we observe a loss of interactions in the core of the α/β structure that is likely to affect folding and stability of ARL3.

Conclusion: Our study confirms that the ARL3 missense variant p.(Tyr90Cys) causes retinitis pigmentosa. In 2016, Strom et al. reported the exact same variant in a mother and two children with RP, labelled ?RP83 in the OMIM database. Now the questionmark can be removed, and ARL3 should be added to the list of genes that may cause non-syndromic dominant retinitis pigmentosa.     

A comparison between two powder compaction parameters of plasticity: The effective medium A parameter and the Heckel 1/K parameter

The purpose of the research was to introduce a procedure to derive a powder compression parameter (EM A) representing particle yield stress using an effective medium equation and to compare the EM A parameter with the Heckel compression parameter (1/K).     

The pentose phosphate pathway and pyruvate carboxylation after neonatal hypoxic-ischemic brain injury

The neonatal brain is vulnerable to oxidative stress, and the pentose phosphate pathway (PPP) may be of particular importance to limit the injury. Furthermore, in the neonatal brain, neurons depend on de novo synthesis of neurotransmitters via pyruvate carboxylase (PC) in astrocytes to increase neurotransmitter pools. In the adult brain, PPP activity increases in response to various injuries while pyruvate carboxylation is reduced after ischemia. However, little is known about the response of these pathways after neonatal hypoxia-ischemia (HI). To this end, 7-day-old rats were subjected to unilateral carotid artery ligation followed by hypoxia. Animals were injected with [1,2-¹³C]glucose during the recovery phase and extracts of cerebral hemispheres ipsi- and contralateral to the operation were analyzed using ¹H- and ¹³C-NMR (nuclear magnetic resonance) spectroscopy and high-performance liquid chromatography (HPLC). After HI, glucose levels were increased and there was evidence of mitochondrial hypometabolism in both hemispheres. Moreover, metabolism via PPP was reduced bilaterally. Ipsilateral glucose metabolism via PC was reduced, but PC activity was relatively preserved compared with glucose metabolism via pyruvate dehydrogenase. The observed reduction in PPP activity after HI may contribute to the increased susceptibility of the neonatal brain to oxidative stress.     

The Fit for Delivery study: rationale for the recommendations and test‐retest reliability of a dietary score measuring adherence to 10 specific recommendations for prevention of excessive weight gain during pregnancy

Aiming at preventing excessive weight gain during pregnancy, 10 specific dietary recommendations are given to pregnant women in the intervention arm of the Norwegian Fit for Delivery (FFD) study. This paper presents the rationale and test‐retest reliability of the food frequency questionnaire (FFQ) and a dietary score measuring adherence to the recommendations. The study is part of the ongoing FFD study, a randomised, controlled, intervention study in nulliparous pregnant women. A 43‐item FFQ was developed for the FFD study. A dietary score was constructed from 10 subscales corresponding to the 10 dietary recommendations. Adding the subscales yielded a score from 0 to 10 with increasing score indicating healthier dietary behaviour. The score was divided into tertiles, grouping participants into low, medium and high adherence to the dietary recommendations. Pregnant women attending ultrasound screening at about week 19 of pregnancy were asked to complete the FFQ twice, 2 weeks apart. Of 154 pregnant women completing the first questionnaire, 106 (69%) completed the form on both occasions and was included in the study. The test‐retest correlations of the score and subscales were r = 0.68 and r = 0.56–0.84, respectively (both P ≤ 0.001). There was 68% test‐retest correct classification of the score and 70–87% of the subscales. In conclusion, acceptable test‐retest reliability of the FFQ and the dietary score was found. The score will be used in the FFD study to measure adherence to the dietary recommendations throughout pregnancy and in the following year post‐partum.     

Sensitivity of regression calibration to non‐perfect validation data with application to the Norwegian Women and Cancer Study

Measurement error occurs when we observe error‐prone surrogates, rather than true values. It is common in observational studies and especially so in epidemiology, in nutritional epidemiology in particular. Correcting for measurement error has become common, and regression calibration is the most popular way to account for measurement error in continuous covariates. We consider its use in the context where there are validation data, which are used to calibrate the true values given the observed covariates. We allow for the case that the true value itself may not be observed in the validation data, but instead, a so‐called reference measure is observed. The regression calibration method relies on certain assumptions.This paper examines possible biases in regression calibration estimators when some of these assumptions are violated. More specifically, we allow for the fact that (i) the reference measure may not necessarily be an ‘alloyed gold standard’ (i.e., unbiased) for the true value; (ii) there may be correlated random subject effects contributing to the surrogate and reference measures in the validation data; and (iii) the calibration model itself may not be the same in the validation study as in the main study; that is, it is not transportable. We expand on previous work to provide a general result, which characterizes potential bias in the regression calibration estimators as a result of any combination of the violations aforementioned. We then illustrate some of the general results with data from the Norwegian Women and Cancer Study. Copyright © 2015 John Wiley & Sons, Ltd.