Two centuries of biodiversity discovery and loss in Singapore.

There is an urgent need for reliable data on the impacts of deforestation on tropical biodiversity. The city-state of Singapore has one of the most detailed biodiversity records in the tropics, dating back to the turn of the 19th century. In 1819, Singapore was almost entirely covered in primary forest, but this has since been largely cleared.

Physiological and Cognitive Determinants of Gait Variability of Asian Population: The Yishun Study.

Introduction: Gait variability is associated with frailty, dementia, and falls. Studies on the association of physiological and cognitive factors with gait variability have seldom included middle-aged adults, even though these adults already experienced loss of muscular strength and postural stability. This study aimed a) to examine and compare the trend of gait variability in men and women, across the adult age spectrum, and b) to identify and compare the contributions of physiological and cognitive factors to gait variability.

Body composition reference values in Singaporean adults using dual-energy X-ray absorptiometry-The Yishun study.

Objectives: This study establishes age- and sex-specific reference values for fat mass index (FMI), lean mass index (LMI), appendicular LMI (aLMI), and body fat distribution indices including Android/Gynoid % fat ratio and Trunk/Limb % fat ratio in multi-ethnic Singaporean adults.

Methods: A population-based cross-sectional study using dual-energy X-ray absorptiometry (Hologic Discovery Wi) was carried out to measure whole body and regional fat and lean mass in community-dwelling adults. A total of 537 adults (57.

Associations of low handgrip strength and hand laterality with cognitive function and functional mobility - the Yishun Study.

Background: Emerging evidence suggest that in addition to low hand grip strength (HGS), HGS asymmetry is associated with declining cognitive and physical functions. We examined the associations of low HGS and asymmetry with cognitive function and functional mobility in older adults.

Methods: Cross-sectional data of 330 community-dwelling adults (55.

Cross-sectional associations of housework with cognitive, physical and sensorimotor functions in younger and older community-dwelling adults: the Yishun Study.

Objectives: Regular moderate-to-vigorous intensity recreational physical activity (PA) improves physical and cognitive functions. However, the age-associated relationships between non-recreational PA and functional ability remain less explored. We examined the associations between housework and functional health among younger and older Singaporean community-dwelling adults.

Associations of fat mass and muscle function but not lean mass with cognitive impairment: The Yishun Study.

Background: Sarcopenia and obesity are reportedly associated with risk of cognitive decline, and sarcopenic obesity (SO) heightens the risk, but the evidence is sparse and inconclusive. This study aimed to examine the association between SO and cognitive impairment.

Methods: A total of 542 community-dwelling adults aged between 21 and 90 years were recruited.

COVID-19 vaccine strategies for Aotearoa New Zealand: a mathematical modelling study.

COVID-19 elimination measures, including border closures have been applied in New Zealand. We have modelled the potential effect of vaccination programmes for opening borders. We used a deterministic age-stratified Susceptible, Exposed, Infectious, Recovered (SEIR) model.

Relationship between BMI with percentage body fat and obesity in Singaporean adults - The Yishun Study.

Background: The main aim of this study was to the determine relationship between Body Mass Index (BMI) and percentage body fat (BF%) in Singaporean adults, derive a prediction model to estimate BF%, and to report population BF%. The secondary aim was to determine the prevalence of overweight and obesity based on BF% threshold and the new risk categories for obesity in Singaporean population.

Methods: This was a population-based study of 542 community-dwelling Singaporeans (21-90 years old, 43.

Coexistence of osteoporosis, sarcopenia and obesity in community-dwelling adults - The Yishun Study.

Objectives: To 1) report prevalence of 'osteosarcopenia' (OS) and osteosarcopenic obesity (OSO) entities using evidence-based diagnostic techniques and definitions, 2) examine if OSO offers additional predictive value of functional decline over its components, and 3) identify associated factors in a multi-racial Southeast Asian population.

Methods: We performed a cross-sectional study of a representative sample of 542 community-dwelling adults (21-90 years old), and assessed anthropometry, cognition, functional performance, and self-report sociodemographic, health and lifestyle questionnaires. Low muscle mass, and the Asian Working Group for Sarcopenia (AWGS) 2019 criteria, were used to assess sarcopenia.

Timed Up and Go (TUG) Reference Values and Predictive Cutoffs for Fall Risk and Disability in Singaporean Community-Dwelling Adults: Yishun Cross-Sectional Study and Singapore Longitudinal Aging Study.

Objectives: The "timed up and go" (TUG) test is a simple and widely used test of overall functional mobility. There is a paucity of TUG normative data among Asian individuals who differ in habitual gait speed and fall risk from Western population. The objectives of this study were to determine TUG reference values and optimum cutoffs predicting prevalent and incident disability for community-dwelling adults.

SPPB reference values and performance in assessing sarcopenia in community-dwelling Singaporeans - Yishun study.

Background: The Short Physical Performance Battery (SPPB) is an established test of physical performance. We provide reference values for SPPB and determine SPPB performance and cut-offs in assessing sarcopenia for Asian community-dwelling older adults.

Methods: Five hundred thirty-eight (57.

Physiological and Cognitive Determinants of Dual-Task Costs for Gait Parameters: The Yishun Study.

Background: Studies indicate that physiological and cognitive aging are causally related and functionally interdependent. However, the relative contribution of physiological factors and cognition to dual-task costs (DTC) of gait parameters has not been well studied. In this cross-sectional study, we examined the trajectory of DTC of gait parameters across the adult age spectrum for both sexes and identified the contributions of physical and cognitive performance to DTC of gait.

Effectiveness of Community-Delivered Functional Power Training Program for Frail and Pre-frail Community-Dwelling Older Adults: a Randomized Controlled Study.

Translation of community-based functional training for older adults to reduce frailty is still lacking. We evaluated the effectiveness and implementation of a community-delivered group-based functional power training (FPT) program for frail older adults within their neighborhoods. A two-arm, multicenter assessor-blind stratified randomized controlled trial was conducted at four local senior activity centers in Singapore.

Fast gait spatiotemporal parameters in adults and association with muscle strength - The Yishun study.

Background: There is limited data on fast gait speed and spatial-temporal parameters across age groups among Asian adults, and the associations between upper and lower extremity muscle strength with gait.

Research Question: What values characterise fast gait spatiotemporal parameters across the age groups of an Asian population? Are hand grip strength (HGS) and knee extension strength (KES) associated with fast gait speed and spatiotemporal parameters?

Methods: Healthy community-living adults between 21-90 years (n = 487) were recruited. Fast gait was assessed using a 6 m instrumented walkway, and spatiotemporal parameters including variability for fast gait speed, stride length, stride width, stride time, stance time, swing time, single support time and double support time were analysed.

Malnutrition and Sarcopenia in Community-Dwelling Adults in Singapore: Yishun Health Study.

Objectives: To determine the overlapping prevalence of malnutrition and sarcopenia and the association between parameters of malnutrition with muscle mass and strength in a community-dwelling Singaporean adult population.

Design: This was a cross-sectional study.

Setting: Large north-eastern residential town of Yishun in Singapore.

Sensorimotor Performance and Reference Values for Fall Risk Assessment in Community-Dwelling Adults: The Yishun Study.

Objective: This study sought to answer the following questions: What are the reference values of sensorimotor performance for fall risk in community-dwelling adults? How do population norms compare with that of other populations? Are younger adults at risk of falls?

Methods: In a cross-sectional study design, sensorimotor functions and fall risk scores of community-dwelling adults were assessed and calculated to derive corresponding fall risk categories. Reference values were determined using the average scores by age group. A total of 542 community-dwelling adults were recruited (21-90 years old) across 10-year (21-60 years) and 5-year age groups (>60 years) to obtain a representative sample of community-dwelling adults in Singapore.

Reference Values of Gait Speed and Gait Spatiotemporal Parameters for a South East Asian Population: The Yishun Study.

Background: Age-related slowing of gait has been reported to start as early as the fifth decade and accelerate beyond the seventh decade of life. A single cut-off for slow gait may not be appropriate for men and women of different ages. We aimed to report reference values for gait speed and spatiotemporal gait parameters of adult age groups in a South East Asian population.

Bone mineral density reference values in Singaporean adults and comparisons for osteoporosis establishment - The Yishun Study.

Background: While there have been studies in Singapore on the prevalence and economic burden of osteoporotic hip fracture, there is a severe lack of reference data on bone mineral density and prevalence of osteoporosis. The purpose of this study is to establish the reference values for BMD and compare prevalence of osteoporotic conditions using other available reference values so as to better understand the status of bone health in Singaporean adults.

Methods: We carried out a population-based cross-sectional study using dual-energy x-ray absorptiometry (Hologic Discovery Wi) to measure the bone mineral density of Singaporean adults aged ≥21 years.

Prevalence and Associated Factors of Sarcopenia in Singaporean Adults-The Yishun Study.

Objectives: To describe the normative values of sarcopenia among community-dwelling adults (≥21 years of age); compare the prevalence of sarcopenia using Asian Working Group for Sarcopenia criteria, 2014 (AWGS2014), Asian Working Group for Sarcopenia criteria, 2019 (AWGS2019), and European Working Group on Sarcopenia in Older People criteria, 2018 (EWGSOP2) guidelines; and identify factors associated with sarcopenia.

Design: Participants were recruited through random sampling. Sarcopenia assessments were performed using a dual-energy x-ray absorptiometry scan (muscle mass), handgrip test (muscle strength), and usual walking test (physical performance).

Extinction rate of discovered and undiscovered plants in Singapore.

Extinction is a key issue in the assessment of global biodiversity. However, many extinction rate measures do not account for species that went extinct before they could be discovered. The highly developed island city-state of Singapore has one of the best-documented tropical floras in the world.

Dynamic interplay between H-current and M-current controls motoneuron hyperexcitability in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a type of motor neuron disease (MND) in which humans lose motor functions due to progressive loss of motoneurons in the cortex, brainstem, and spinal cord. In patients and in animal models of MND it has been observed that there is a change in the properties of motoneurons, termed neuronal hyperexcitability, which is an exaggerated response of the neurons to a stimulus. Previous studies suggested neuronal excitability is one of the leading causes for neuronal loss, however the factors that instigate excitability in neurons over the course of disease onset and progression are not well understood, as these studies have looked mainly at embryonic or early postnatal stages (pre-symptomatic).

Regulation of the NRF2 transcription factor by andrographolide and organic extracts from plant endophytes.

The transcription factor NF-E2 Related Factor-2 (NRF2) is an important drug target. Activation of NRF2 has chemopreventive effects in cancer and exerts beneficial effects in a number of diseases, including neurodegenerative diseases, inflammatory diseases, hepatosteatosis, obesity and insulin resistance. Hence, there have been great efforts to discover and characterize novel NRF2 activators.