Moderate-to-vigorous physical activity modifies the relationship between sedentary time and sarcopenia: the Tromsø Study 2015–2016

Background: Sarcopenia is an age-related muscle disease primarily characterized by reductions in muscle strength that increases the risk of falls, fractures, cognitive impairment, and mortality. Exercise is currently preferred in prevention and treatment, but it is unknown how different habitual physical activity and sedentary behaviour patterns associate with sarcopenia status. The purpose of the present study was to compare associations of these patterns with probable sarcopenia in older adults. Methods: In 3653 community-dwelling participants (51% women) aged 60–84 years from the seventh survey of the Tromsø Study, we assessed objective physical activity and sedentary behaviour collected over 8 days (ActiGraph wGT3X-BT Accelerometer), grip strength (Jamar+ Digital Dynamometer), five-repetition chair stands, and self-reported disease. We combined tertiles of sedentary (SED) time and moderate-to-vigorous physical activity (MVPA) to create nine different activity profiles (SEDHIGH, SEDMOD, and SEDLOW combined with MVPAHIGH, MVPAMOD, or MVPALOW). Multiple logistic regression models were used to examine how these profiles associated with probable sarcopenia, defined by low handgrip strength and/or slow chair stands time according to the revised European Working Group on Sarcopenia in Older People criteria. Results: Probable sarcopenia was present in 227 (6.2%) participants. Men with probable sarcopenia had on average 35.3 min more SED time and 20 min less MVPA compared with participants without sarcopenia (P HIGH–MVPALOW reference activity profile (714.2 min SED/day and 10.4 min MVPA/day), the SEDHIGH–MVPAMOD profile (697.1 min SED/day and 31.5 min MVPA/day) had significantly lower odds ratio (OR) for probable sarcopenia (OR 0.17, 95% confidence interval [CI] 0.08–0.35), while the SEDLOW–MVPALOW profile (482.9 min SED/day and 11.0 min MVPA/day) did not (OR 0.72, 95% CI 0.47–1.11). These findings were not influenced by age, sex, smoking, or self-reported diseases, and higher levels of MVPA did not further decrease ORs for probable sarcopenia. Conclusions: Older adults who achieve moderate amounts of MVPA have reduced odds for probable sarcopenia, even when they have high sedentary time. Those with low sedentary time did not have reduced odds for probable sarcopenia when they also had low amounts of MVPA. These findings need confirmation in longitudinal studies but suggest that interventions for preventing sarcopenia should prioritize increasing MVPA over reducing sedentary behaviour

A study assessing the association of glycated hemoglobin a1C (HbA1C) associated variants with HbA1C, chronic kidney disease and diabetic retinopathy in populations of asian ancestry

10.1371/journal.pone.0079767PLoS ONE811-POLN

Gender Differences in White Matter Microstructure

Sexual dimorphism in human brain structure is well recognised, but little is known about gender differences in white matter microstructure. We used diffusion tensor imaging to explore differences in fractional anisotropy (FA), an index of microstructural integrity.A whole brain analysis of 135 matched subjects (90 men and 45 women) using a 1.5 T scanner. A region of interest (ROI) analysis was used to confirm those results where proximity to CSF raised the possibility of partial-volume artefact.Men had higher fractional anisotropy (FA) in cerebellar white matter and in the left superior longitudinal fasciculus; women had higher FA in the corpus callosum, confirmed by ROI.The size of the differences was substantial--of the same order as that attributed to some pathology--suggesting gender may be a potentially significant confound in unbalanced clinical studies. There are several previous reports of difference in the corpus callosum, though they disagree on the direction of difference; our findings in the cerebellum and the superior longitudinal fasciculus have not previously been noted. The higher FA in women may reflect greater efficiency of a smaller corpus callosum. The relatively increased superior longitudinal fasciculus and cerebellar FA in men may reflect their increased language lateralisation and enhanced motor development, respectively

A systematic review of the relationship between subchondral bone features, pain and structural pathology in peripheral joint osteoarthritis

Introduction: Bone is an integral part of the osteoarthritis (OA) process. We conducted a systematic literature review in order to understand the relationship between non-conventional radiographic imaging of subchondral bone, pain, structural pathology and joint replacement in peripheral joint OA. Methods: A search of the Medline, EMBASE and Cochrane library databases was performed for original articles reporting association between non-conventional radiographic imaging-assessed subchondral bone pathologies and joint replacement, pain or structural progression in knee, hip, hand, ankle and foot OA. Each association was qualitatively characterised by a synthesis of the data from each analysis based upon study design, adequacy of covariate adjustment and quality scoring. Results: In total 2456 abstracts were screened and 139 papers were included (70 cross-sectional, 71 longitudinal analyses; 116 knee, 15 hip, six hand, two ankle and involved 113 MRI, eight DXA, four CT, eight scintigraphic and eight 2D shape analyses). BMLs, osteophytes and bone shape were independently associated with structural progression or joint replacement. BMLs and bone shape were independently associated with longitudinal change in pain and incident frequent knee pain respectively. Conclusion: Subchondral bone features have independent associations with structural progression, pain and joint replacement in peripheral OA in the hip and hand but especially in the knee. For peripheral OA sites other than the knee, there are fewer associations and independent associations of bone pathologies with these important OA outcomes which may reflect fewer studies; for example the foot and ankle were poorly studied. Subchondral OA bone appears to be a relevant therapeutic target. Systematic review: PROSPERO registration number: CRD 4201300500

Melioidosis: A review

The disease melioidosis, caused by the bacterium Burkholderia pseudomallei, remains an important and sometimes neglected cause of disease in tropical regions of Australia. Infection may present in myriad ways, and diagnosis often requires consideration of this organism prior to culture. Laboratory identification of B. pseudomallei requires specialised testing beyond that available in many routine diagnostic microbiology laboratories. For this reason, cases outside of the traditional endemic zone, often occurring years after initial exposure to the organism, may remain undiagnosed or are delayed in diagnosis. Furthermore, the high levels of intrinsic antimicrobial resistance associated with B. pseudomallei often render empirical therapies ineffective. Health professionals, particularly those in rural and remote areas of Australia, must consider melioidosis in their differential diagnoses and remain abreast of advances in the field of this important emerging disease

Melioidosis: A review

The disease melioidosis, caused by the bacterium Burkholderia pseudomallei, remains an important and sometimes neglected cause of disease in tropical regions of Australia. Infection may present in myriad ways, and diagnosis often requires consideration of this organism prior to culture. Laboratory identification of B. pseudomallei requires specialised testing beyond that available in many routine diagnostic microbiology laboratories. For this reason, cases outside of the traditional endemic zone, often occurring years after initial exposure to the organism, may remain undiagnosed or are delayed in diagnosis. Furthermore, the high levels of intrinsic antimicrobial resistance associated with B. pseudomallei often render empirical therapies ineffective. Health professionals, particularly those in rural and remote areas of Australia, must consider melioidosis in their differential diagnoses and remain abreast of advances in the field of this important emerging disease

Assessing the Causality between Blood Pressure and Retinal Vascular Caliber through Mendelian Randomisation

We aimed to determine the association between blood pressure (BP) and retinal vascular caliber changes that were free from confounders and reverse causation by using Mendelian randomisation. A total of 6528 participants from a multi-ethnic cohort (Chinese, Malays, and Indians) in Singapore were included in this study. Retinal arteriolar and venular caliber was measured by a semi-automated computer program. Genotyping was done using Illumina 610-quad chips. Meta-analysis of association between BP, and retinal arteriolar and venular caliber across three ethnic groups was performed both in conventional linear regression and Mendelian randomisation framework with a genetic risk score of BP as an instrumental variable. In multiple linear regression models, each 10 mm Hg increase in systolic BP, diastolic BP, and mean arterial BP (MAP) was associated with significant decreases in retinal arteriolar caliber of a 1.4, 3.0, and 2.6 μm, and significant decreases in retinal venular caliber of a 0.6, 0.7, and 0.9 μm, respectively. In a Mendelian randomisation model, only associations between DBP and MAP and retinal arteriolar narrowing remained yet its significance was greatly reduced. Our data showed weak evidence of a causal relationship between elevated BP and retinal arteriolar narrowing

Development and validation of an instrument for assessing high-school students’ perceptions of socio-scientific issues-based learning in biology

© 2020, Springer Nature B.V. In this research, we developed and validate an instrument for assessing high-school students’ perceptions of socio-scientific issues (SSI)-based learning in biology. The development of the instrument was carried out using the following four steps: item formulation, content validation, construct validation and reliability calculation. According to an extensive literature review, 28 initial items were formulated for four SSI-based instruction aspects: (1) contextualisation of SSI, (2) student involvement, (3) student attitudes towards SSI-learning and (4) SSI-based learning objectives. Based on the pilot study conducted for construct validation, 24 items were successfully constructed for the four scales and subsequently administered in biology classrooms to 151 students. Factor analysis showed that each of the 24 items had a factor loading at least 0.40 on its own scale and no other scale. Moreover, the four scales accounted for 58.32% of the total variance and the alpha reliability coefficients for the scales ranged from 0.75 to 0.85. According to these findings, the SSI-based Learning Environment Inventory in Biology is valid, reliable and useful