Effects of vitamin D deficiency on neurobehavioural outcomes in children: a systematic review [version 1; peer review: 2 approved]

Introduction: Vitamin D plays an important role in brain development in experimental studies; however, the effect of vitamin D deficiency on child development remains inadequately characterized. We aimed to estimate the effects of vitamin D deficiency on neurobehavioural outcomes in children up to 18 years of age. Methods: We searched PubMed, EMBASE, PsycINFO, Scopus, Cochrane Library, Web of Science and Open Grey for published studies up to 10th January 2020. We included all studies that assessed the effects of maternal or child vitamin D status or vitamin D supplementation on neurobehavioural outcomes in children. Study findings were synthesized qualitatively as the high level of heterogeneity in study populations and methodologies precluded a quantitative meta-analysis. Results: Our search identified 5,633 studies, of which 32 studies with 31,445 participants from 18 countries were included in the systematic review. Of the studies identified, two were randomized controlled trials (RCTs) of vitamin D supplementation in children, while 30 were observational. One RCT (n=55) reported a beneficial effect of supplementation with lower doses compared to higher doses of vitamin D on motor development while the other RCT (n=70) found no beneficial effect of vitamin D supplementation on cognition in extremely preterm infants. Twelve mother-child studies (n=17,136) and five studies in children (n=1,091) reported an association between low maternal or child 25-hydroxyvitamin D levels and impaired neurobehavioural outcomes in children, while 15 mother-child studies (n=20,778) and eight studies in children (n=7,496) reported no association. Conclusions: Although animal studies point to an effect of vitamin D deficiency on brain development, there are few studies on the effects of vitamin D deficiency on neurobehavioural outcomes in children and their findings are inconsistent. There is a need for well-conducted, adequately powered studies to further determine these effects in children. Registration: PROSPERO ID CRD42018087619 ; registered on 15 February 2018

Superplastic forming characteristics of AZ41 magnesium alloy

An AZ41 magnesium alloy in the hot-rolled condition without further thermomechanical processing to modify its microstructure was investigated to establish its suitability for use within a superplastic forming process and to establish optimum forming parameters. Formability was assessed using elevated temperature tensile testing and hot gas bulging, across a range of strain rates (1×10−1−1×10−3 s−1) and temperatures (350−450 °C). Circle grid analysis with GOM Aramis cameras was used to understand peak strains and material thinning in relation to industrial forming processes. Post forming EBSD and STEM analysis was conducted to understand the mechanisms responsible for the materials formability, with dynamic recrystallization being clearly evident. Peak elongation of 520% was achieved at 450 °C and 1×10−3 s−1; industrially relevant elongation was achieved at 1×10−2 s−1 at both 450 °C (195%) and 400 °C (170%)

Accuracy of clinical evaluation and MRI reporting compared to knee arthroscopic findings

Background: Intra-articular knee injuries are diagnosed using multiple modalities including Magnetic Resonance Imaging (MRI) or arthrography and various clinical tests. However, there is a high incidence of false negative and false positive findings in MRI assessment. The deeper intra articular structures such as the medial meniscus brings about the high incidence of false positives and false negatives in MRI assessment. The clinical tests also have benefits in diagnosing these injuries but its sensitivity and specificity is also under question. Arthroscopy has quickly become the “gold standard” but diagnostic arthroscopy on its own is rarely done and is only done before a treatment procedure. No regional studies have been done and only a few handful studies done worldwide especially after recent advances in 3 tesla MRI apparatus.Objectives: The aim of this study was to assess the diagnostic accuracy based on various clinical tests and validity of MRI in our populace in association with arthroscopic findings.Design: This was a multi-center prospective cross-sectional study conducted at Aga Khan University Hospital Nairobi (AKUHN), Kikuyu Hospital, M.P. Shah Hospital and Kijabe Hospital over a six-month period.Methodology: Preoperative clinical diagnosis based on various specific tests and preoperative MRI was compared with operative diagnostic arthroscopic outcomes separately to ascertain the accuracy of each using arthroscopy as the “gold standard”. The study population categorical variables was described and summarized as percentages and counts by use of frequency tables and continuous variables was summarized using central tendency and dispersion (minimum, maximum, range, IQR, mean, standard deviation, median). Sensitivity, specificity, positive and negative predictive values, and finally accuracy was then tabulated.Results: One hundred and forty patients were recruited with 85 males and 55 females undergoing knee arthroscopy. One hundred and forty six knees were evaluated with the right knee (53.1%) more injured than the left (49%). Lateral meniscus (53.1%) was found to be more injured than the medial meniscus (46.8%) with the posterior horn (medial-73.3%; lateral-60%) of the meniscus being the commonest part of the meniscus injured. Anterior Cruciate Ligament (ACL) injury (39 patients) was more common than PCL injury (9 patients). Among the clinical tests, joint-line tenderness was the most sensitive test (medial-69.1%; lateral-64.4%) and the McMurrays test most specific (medial-92.2%; lateral-91.9%). Thessalys test was not found to be more sensitive (medial-58.8%; lateral-50.8%) or specific (medial-89.6%; lateral-88.4%) as reported previously. For ACL tears, Lachman test was specific (96.4%) and the anterior drawer test was more sensitive (81.8%). Accuracy for medial meniscus tear (47%) on MRI was more than lateral meniscus (41%). MRI did poorly in diagnosing ACL tears due to over reporting of partial ACL tears (complete ACL tear-23%; partial ACL tear-4%).Conclusion: The diagnosis of intra-articular injuries is still a challenge and both clinical examination and MRI has its limitations. MRI reporting is no better than clinical examination in diagnosing meniscal tears and clinical examination is better at diagnosing cruciate ligament injuries than MRI reporting. Overall the accuracy of MRI reporting is poor in our set-up.Keywords: Knee Arthroscopy, Knee MRI, 3 Tesla, Accuracy, Knee examinatio

Tennis player J. Willard after hitting a forehand shot, New South Wales, ca. 1930 [picture].

Title devised from accompanying information where available.; Part of the: Fairfax archive of glass plate negatives.; Fairfax number: 4918.; Condition: silvering.; Also available online at: http://nla.gov.au/nla.pic-vn6251103; Acquired from Fairfax Media, 2012

Effects of vitamin D deficiency on neurobehavioural outcomes in children: a systematic review

Introduction: Vitamin D plays an important role in brain development in experimental studies; however, the effect of vitamin D deficiency on child development remains inadequately characterized. We aimed to estimate the effects of vitamin D deficiency on neurobehavioural outcomes in children up to 18 years of age. Methods: We searched PubMed, EMBASE, PsycINFO, Scopus, Cochrane Library, Web of Science and Open Grey for published studies up to 10th January 2020. We included all studies that assessed the effects of maternal or child vitamin D status or vitamin D supplementation on neurobehavioural outcomes in children. Study findings were synthesized qualitatively as the high level of heterogeneity in study populations and methodologies precluded a quantitative meta-analysis. Results: Our search identified 5,633 studies, of which 31 studies with 31,375 participants from 18 countries were included in the systematic review. Of the studies identified, one was a randomised controlled trial (RCT) of vitamin D supplementation in children, while 30 were observational. The RCT (n=55) reported a beneficial effect of supplementation with lower doses compared to higher doses of vitamin D on motor development. Twelve mother-child studies (n=17,136) and five studies in children (n=1,091) reported an association between low maternal or child 25-hydroxyvitamin D levels and impaired neurobehavioural outcomes in children, while 15 mother-child studies (n=20,778) and eight studies in children (n=7,496) reported no association. Conclusions: Although animal studies point to an effect of vitamin D deficiency on brain development, there are few studies on the effects of vitamin D deficiency on neurobehavioural outcomes in children and their findings are inconsistent. There is a need for well-conducted, adequately powered studies to further determine these effects in children. Registration: PROSPERO ID CRD42018087619 ; registered on 15 February 2018