Genetic influence on exercise-induced changes in physical function among mobility-limited older adults

To date, physical exercise is the only intervention consistently demonstrated to attenuate age-related declines in physical function. However, variability exists in seniors' responsiveness to training. One potential source of variability is the insertion (I allele) or deletion (D allele) of a 287 bp fragment in intron 16 of the angiotensin-converting enzyme (ACE) gene. This polymorphism is known to influence a variety of physiological adaptions to exercise. However, evidence is inconclusive regarding the influence of this polymorphism on older adults' functional responses to exercise. This study aimed to evaluate the association of ACE I/D genotypes with changes in physical function among Caucasian older adults ( n = 283) following 12 mo of either structured, multimodal physical activity or health education. Measures of physical function included usual-paced gait speed and performance on the Short Physical Performance Battery (SPPB). After checking Hardy-Weinberg equilibrium, we used using linear regression to evaluate the genotype*treatment interaction for each outcome. Covariates included clinic site, body mass index, age, sex, baseline score, comorbidity, and use of angiotensin receptor blockers or ACE inhibitors. Genotype frequencies [II (19.4%), ID (42.4%), DD (38.2%)] were in Hardy-Weinberg equilibrium ( P > 0.05). The genotype*treatment interaction was statistically significant for both gait speed ( P = 0.002) and SPPB ( P = 0.020). Exercise improved gait speed by 0.06 ± 0.01 m/sec and SPPB score by 0.72 ± 0.16 points among those with at least one D allele (ID/DD carriers), but function was not improved among II carriers. Thus, ACE I/D genotype appears to play a role in modulating functional responses to exercise training in seniors.

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132 Physical Function Comparison of Acutely Unwell COVID-Negative Older Adults Pre-Pandemic and Through-Pandemic; “Covid-Protected”

Age and Ageing ◽

10.1093/ageing/afab030.93 ◽

2021 ◽

Vol 50 (Supplement_1) ◽

pp. i12-i42

Author(s):

S Ritchie ◽

C Snape ◽

N Triteos ◽

R Vamadevan ◽

L Olesk ◽

...

Keyword(s):

Older Adults ◽

Mortality Rate ◽

Hospital Mortality ◽

Physical Function ◽

Gait Speed ◽

Hospital Length ◽

Hospital Length Of Stay ◽

Ethical Review ◽

Short Period ◽

Elderly Mobility

Abstract Introduction The risk of severe morbidity after COVID-19 infection is high in older adults (Lithander et al, 2020). Subsequent responsive UK Government guidance for older adults included self-isolation during the pandemic. It is therefore hypothesised that during the pandemic older adults are inadvertently deconditioned due to iatrogenic factors such as inactivity, social isolation, hospital-avoidance and malnutrition, and present with reduced resilience to illness and lower levels of function. The OPU continued to admit COVID-negative, or recently termed “COVID-protected”, patients throughout the pandemic. Data captured prior to, and during the COVID-19 pandemic has been compared to explore the implications on older adults, and elicit whether they are protected from the consequences of the pandemic? Method Demographic and physical function data (average 6 m gait-speed, Elderly Mobility Scale) were captured pre- and through-pandemic for all patients admitted to a COVID-negative OPU ward over a one month period. Ethical review was provided through local Trust governance process. Results Pre-pandemic 2019 (n = 67, mean(±SD) age 82.7(±8.2) years, 61%, hospital length-of-stay (LOS) 7.9(±7.3) days, hospital mortality-rate 7.2%) and through-pandemic 2020 (n = 73, 83.1(±8.3) years, 59%♀, LOS 9.0(±9.1) days, hospital mortality-rate 7.5%) data were captured during July 2019 and May 2020 respectively. There were no between-group differences in age [t(−.313) = 138, p = 0.755], gender [X2, 1 df, p = 0.782], LOS [t(0.78) = 134, p = 0.44], or hospital mortality-rate [X2 1 df, p = 0.96]. Through-pandemic patients had a significantly slower 6 m gait-speed (0.11(±0.05) m.s-1) than pre-pandemic (0.16(±0.24) m.s-1); [t(2.74) = 93, p = 0.007] and lower median (IQR) Elderly Mobility Scale (4(6 IQR) vs 9 (12 IQR) [u = 866, p = 0.015]). Conclusion Our data indicates this relatively short period of self-isolation might have significant implications on the physical function of older adults. The likely mechanism is iatrogenic deconditioning. Critical Public Health and policy responses are required to mitigate these unforeseen risks by deploying prehabilitative counter-measures and accurately targeted hospital and community rehabilitation.

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IMPLEMENTATION OF A COMMUNITY WALKING PROGRAM (WALK ON!) FOR FUNCTIONALLY-LIMITED OLDER ADULTS

Journal of Frailty & Aging ◽

10.14283/jfa.2020.12 ◽

2020 ◽

pp. 1-7

Author(s):

B.J. Nicklas ◽

E.A. Chmelo ◽

J. Sheedy ◽

J.B. Moore

Keyword(s):

Older Adults ◽

Focus Group ◽

Physical Function ◽

Gait Speed ◽

Assistive Device ◽

Walking Ability ◽

Mobility Limitations ◽

Long Distance ◽

Walking Program ◽

Usual Gait Speed

Background: Walking interventions improve physical function, reduce fall risk, and prevent mobility disability—even in those with compromised walking ability. However, most prior studies have been conducted in controlled research settings, with no dissemination of an evidence-based walking program for older adults who have mobility limitations and/or are socially isolated. Objectives: This study reports data on the feasibility and acceptability of a community-based walking program (Walk On!) for older adults who are functionally limited, and assesses changes in physical function among attendees. The program sessions focused on long-distance walking, and took place for one-hour, for two days/week, and for 12 weeks at a time. Design: Pilot implementation study. Setting: Local church in Winston-Salem, NC. Participants: 49 program participants; Measurements: Physical function battery and satisfaction survey data, as well as formative evaluation data from six attendees of a focus group, are reported. Results: The majority of the participants were >75 years (71%), female (65%), and presented with low levels of physical function (usual gait speed=0.79±0.16; 30.6% used an assistive device). Satisfaction with the program was high (100% would recommend it to others) and focus group results were overwhelmingly positive. Mean attendance to scheduled sessions was 77%±21%, and 63% of participants attended at least 75% of scheduled sessions (n=8 attended 100%). On average, participants improved their 6-min walk distance by 8.9%, their SPPB score by 15.4%, their timed-up-go time by 9.0%, and their usual gait speed by 11.4%. Conclusion: The results of the initial evaluation of Walk On! show high feasibility and acceptability of the program, as well as efficacy for improving physical function. Further research is needed to evaluate a delivery method for wider implementation of the program and to definitively test its effectiveness for improving function and other health benefits.

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Solving Hardy-Weinberg with Geometry: An Integration of Biology and Math

The American Biology Teacher ◽

10.1525/abt.2017.79.4.309 ◽

2017 ◽

Vol 79 (4) ◽

pp. 309-312

Author(s):

Laura A. Schoenle ◽

Matthew Thomas

Keyword(s):

Scientific Theory ◽

Geometric Interpretation ◽

Student Understanding ◽

Weinberg Equilibrium ◽

The Core ◽

Distributive Property ◽

Genotype Frequencies ◽

Hardy Weinberg Equilibrium ◽

Using Data ◽

And Mathematics

Introducing Hardy-Weinberg equilibrium into the high school or college classroom can be difficult because many students struggle with the mathematical formalism of the Hardy-Weinberg equations. Despite the potential difficulties, incorporating Hardy-Weinberg into the curriculum can provide students with the opportunity to investigate a scientific theory using data and integrate across the disciplines of biology and mathematics. We present a geometric way to interpret and visualize Hardy-Weinberg equilibrium, allowing students to focus on the core ideas without algebraic baggage. We also introduce interactive applets that draw on the distributive property of mathematics to allow students to experiment in real time. With the applets, students can observe the effects of changing allele frequencies on genotype frequencies in a population at Hardy-Weinberg equilibrium. Anecdotally, we found use of the geometric interpretation led to deeper student understanding of the concepts and improved the students' ability to solve Hardy-Weinberg-related problems. Students can use the ideas and tools provided here to draw connections between the biology and mathematics, as well as between algebra and geometry.

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Genetics of Cronartium ribicola. III. Mating System

Canadian Journal of Botany ◽

10.1139/b96-222 ◽

1996 ◽

Vol 74 (11) ◽

pp. 1852-1859 ◽

Cited By ~ 20

Author(s):

Matthew A. Gitzendanner ◽

Gayle E. Dupper ◽

Eleanor E. White ◽

Brett M. Foord ◽

Paul D. Hodgskiss ◽

...

Keyword(s):

Mating System ◽

Genetic Recombination ◽

Random Mating ◽

Cronartium Ribicola ◽

White Pine Blister Rust ◽

Mendelian Segregation ◽

Weinberg Equilibrium ◽

Forest Pathogen ◽

Genotype Frequencies ◽

Hardy Weinberg Equilibrium

Lack of genetic markers has hindered the study of the mating system of Cronartium ribicola, an exotic forest pathogen Meeting natural and cultivated white pines throughout North America. Isozymes, randomly amplified polymorphic DNA (RAPDs), and restriction length polymorphisms (RFLPs) were used to study the mating system of this rust. Heterozygosity (outcrossing) in diploid telia was demonstrated by analysis of cultures derived from the meiotic products (basidiospores) of individual telia. Families of basidiospores cultured from single telia were used to test for Mendelian segregation and for conformance of loci to Hardy–Weinberg equilibrium. A total of 18 polymorphic loci were identified with the three marker systems. All except for three RAPD loci showed Mendelian segregation in the single-telium families. To quantify the level of outcrossing, gene and genotype frequencies were calculated for families from a single population. Up to 24 families were surveyed with isozymes, 14 with RAPDs, and 18 with RFLPs. Except for one isozyme locus (MPI) in one sample, all 14 loci tested with these families were in Hardy–Weinberg equilibrium, indicating random mating. Further studies, with a different sample from the same population, showed all three isozyme loci to be in Hardy–Weinberg equilibrium. The three marker systems were consistent as to the amount of variation detected. Resistance selection and breeding programs must consider the implications of genetic recombination that outcrossing affords the rust. Keywords: isozymes, RAPDs, RFLPs, Hardy–Weinberg equilibrium, white pine blister rust.

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Disequilibrium of Human Platelet Antigen 1 (HPA-1) in U.S. Population

Blood ◽

10.1182/blood.v112.11.5466.5466 ◽

2008 ◽

Vol 112 (11) ◽

pp. 5466-5466

Author(s):

Tyler Davi d Hutchinson ◽

Yuhua Song ◽

Kevin Trainor ◽

Ghazala Hashmi

Keyword(s):

Human Platelet ◽

Embryo Implantation ◽

The United States ◽

Implantation Failure ◽

Random Group ◽

Weinberg Equilibrium ◽

Genotype Frequencies ◽

Chi Squared ◽

Human Platelet Antigen ◽

Hardy Weinberg Equilibrium

Abstract Background: Alloimmunization against Human Platelet Antigens (HPA) is associated with Neonatal Alloimmune Thrombocytopenia (NAIT), post-transfusion purpura and refractoriness for platelet transfusion. A flexible BeadChip™ design was developed to simultaneously detect 22 platelet antigens, including HPA-1, and used to assay over 1,000 random blood donors from across the United States. Methods: Samples from 19 labs/centers from across the country were assayed for 11 HPA loci (HPA-1 through 9, 11 and 15) using the BioArray Solutions HPA Assay. Each locus was independently assessed for Hardy-Weinberg Equilibrium. Results: Allele and genotype frequencies for each locus were reported. Platelet antigens HPA-2 through HPA-9, HPA-11 and HPA-15 were all found to be in Hardy-Weinberg Equilibrium with a Chi-Squared value of <3.84 (1 degree of freedom, 5% confidence interval). HPA-1, however, did not exhibit Hardy-Weinberg Equilibrium yielding a Chi-Squared value of 43.4. Conclusions: After reaffirming there was no sampling preference by inclusion of a second blinded random group, it was acknowledged that HPA-1 did not conform to a Mendelian distribution of alleles. The lower incidence of heterozygote HPA-1 individuals may lend credence to the recent finding by Ivanov et al (Akush Ginekol, 2007) linking the polymorphism in GPIIIa that is responsible for the HPA-1 antigen with embryo implantation failure. Further research may help elucidate the causes behind the HPA-1 disequilibrium and how much implantation failure impacts HPA-1 frequencies.

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A test for Hardy-Weinberg equilibrium on the X chromosome for sex-biased admixed populations

10.1101/552794 ◽

2019 ◽

Author(s):

Daniel Backenroth ◽

Shai Carmi

Keyword(s):

X Chromosome ◽

Random Mating ◽

Allele Frequencies ◽

Ratio Test ◽

Weinberg Equilibrium ◽

Genotype Frequencies ◽

Genome Wide ◽

Control Step ◽

Hardy Weinberg Equilibrium ◽

Males And Females

AbstractGenome-wide scans for deviations from Hardy-Weinberg equilibrium (HWE) are commonly applied to detect genotyping errors. In contrast to the autosomes, genotype frequencies on the X chromosome do not reach HWE within a single generation. Instead, if allele frequencies in males and females initially differ, they oscillate for a few generations towards equilibrium. Several populations world-wide have experienced recent sex-biased admixture, namely, their male and female founders differed in ancestry and thus in allele frequencies. Sex-biased admixture makes testing for HWE difficult on X, because deviations are naturally expected, even under random mating post-admixture and error-free genotyping. In this paper, we develop a likelihood ratio test and a χ2 test that detect deviations from HWE on X while allowing for natural deviations due to sex-biased admixture. We demonstrate by simulations that our tests are powerful for detecting deviations due to non-random mating, while at the same time they do not reject the null under historical sex-biased admixture and random mating thereafter. We also demonstrate that when applied to 1000 Genomes project populations (e.g., as a quality control step), our tests reject fewer SNPs (among those showing frequency differences between the sexes) than other tests.

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

BMJ Open ◽

10.1136/bmjopen-2021-052557 ◽

2021 ◽

Vol 11 (11) ◽

pp. e052557

Author(s):

Shuen Yee Lee ◽

Benedict Wei Jun Pang ◽

Lay Khoon Lau ◽

Khalid Abdul Jabbar ◽

Wei Ting Seah ◽

...

Keyword(s):

Older Adults ◽

Physical Function ◽

Gait Speed ◽

High Volume ◽

Community Dwelling ◽

Functional Health ◽

Attention And Memory ◽

Recreational Physical Activity ◽

Cross Sectional ◽

Sit To Stand

ObjectivesRegular 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.DesignCross-sectional study.Setting and participantsYounger (<65 years, n=249) and older (≥65 years, n=240) community-dwelling adults were randomly recruited from a large residential town in Singapore.Outcome measuresPhysical function was assessed using Short Physical Performance Battery (SPPB), repeated-chair-sit-to-stand and gait speed. Cognitive and sensorimotor functions were assessed using Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Physiological Profile Assessment (PPA), respectively.MethodsLight housework (LH) and heavy housework (HH), recreational, and occupational and transport-related PAs were assessed using PA questionnaires. Participants were dichotomised into low-volume and high-volume LH and HH groups. Results were adjusted for level of recreational and other non-recreational PAs.ResultsAmong older but not younger adults, RBANS scores were 8% and 5% higher in high HH and LH groups compared with low HH and LH groups, respectively (p=0.012 and p=0.016). Specifically, HH was associated with 14% higher attention score (p=0.014), and LH was associated with 12% and 8% higher immediate and delayed memory scores, respectively (p<0.001 and p=0.004). In older adults, sit-to-stand time and PPA scores were 8% and 23% lower in the high HH group than the low HH group, respectively (p=0.011 and p=0.040). SPPB and gait speed did not differ with age or HH. LH was not associated with physical or sensorimotor function.ConclusionsAmong older adults, housework is associated with higher cognitive function, specifically in attention and memory. Associations of housework with physical function and sensorimotor performance were intensity dependent. Housework PA is positively associated with functional health among community-dwelling older adults, independent of recreation and other non-recreational PAs. Further longitudinal and intervention studies are needed to establish causality.

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Aging With HIV: Inflammation Is Associated With Pain, Poorer Physical Function, and Frailty

Innovation in Aging ◽

10.1093/geroni/igaa057.1072 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 334-334

Author(s):

Heather Derry ◽

Carrie Johnston ◽

Chelsie Burchett ◽

Eugenia Siegler ◽

Marshall Glesby

Keyword(s):

Older Adults ◽

Physical Function ◽

Inflammatory Markers ◽

Smoking Status ◽

Well Being ◽

People Living With Hiv ◽

Cognitive Complaints ◽

Age Related ◽

Comorbidity Burden ◽

Ifn Γ

Abstract With advances in antiretroviral therapies, people living with HIV have life expectancies similar to their HIV-negative peers. Yet, they experience elevated multi-morbidity that can compromise quality of life as they age. Links between inflammation and accelerated aging may inform interventions, but these links are understudied in older adults with HIV. We investigated cross-sectional relationships between inflammation, well-being, and geriatric syndromes among 161 HIV-positive older adults. Participants provided fasting blood samples (for serum cytokines and CRP) and completed surveys (MOS-HIV; falls) and cognitive (MoCA) and frailty assessments (using Fried criteria). Adjusted linear and logistic regression models tested relationships between inflammatory markers and age-related health outcomes, controlling for age, gender, BMI, race, comorbidity burden, statin use, and smoking status. 93% had suppressed viral load. 11% had CRP levels suggesting possible acute illness (>10 mg/L) and were excluded from analyses. Participants with higher IFN-γ reported greater pain (p=0.003), greater cognitive complaints (p=.02), and worse physical function (p=0.04), than those with lower IFN-γ. Similarly, higher IL-6 levels were related to worse physical function (p=0.01) and slightly greater cognitive complaints (p=0.06), but were not significantly related to pain in adjusted models. Compared to those with lower IL-6, those with higher IL-6 levels were more likely to be frail (p=0.04). CRP was not significantly related to these outcomes. Six-month fall history and objective cognitive scores were not significantly related to the assessed inflammatory markers. Our results illustrate key, expected links between inflammatory processes, frailty, physical function, and pain among older adults with HIV.

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Resistance training improves mobility disability in community-dwelling older adults: a meta-analysis

Innovation in Aging ◽

10.1093/geroni/igab046.3253 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. 904-904

Author(s):

Christina Prevett ◽

Kevin Moncion ◽

Stuart Phillips ◽

Julie Richardson ◽

Ada Tang

Keyword(s):

Older Adults ◽

Resistance Training ◽

Physical Function ◽

Gait Speed ◽

Positive Impact ◽

Community Dwelling ◽

Mobility Disability ◽

Exercise Interventions ◽

Walking Capacity ◽

Community Dwelling Older Adults

Abstract Mobility disability is the impairment in function that affects the performance of daily tasks due to declines in physical function. Exercise interventions, particular resistance training, may have a positive impact on mobility disability, but the evidence for the effects of resistance training in older adults with mobility disability has not been previously systematically reviewed. This study was a systematic review of evidence related to resistance training on physical function for adults over 65 years of age with mobility disability. Four databases (PEDro, MedLine, Ovid, Web of Science) were searched from inception to February 2, 2021 for randomized controlled trials. Twenty-four articles from 22 studies (3,656 participants) were included in the review. Mean participant age ranged from 63-87 years and exercise interventions ranged from 10 weeks to 12 months in duration. Greater changes in 6-minute Walk Test (6MWT) distance (n=638, p<0.0001; mean difference (MD) 16.1 metres; 95%CI 12.3-19.9), lower extremity strength (n=785, p<0.0001; standard MD 2.01; 95%CI 1.27-2.75) and usual gait speed (n=2,106, p<0.001; MD 0.05 metres/second, 95%CI 0.03-0.07) were seen with resistance training as compared to control. These results were maintained if resistance training was a sole intervention or a component of a multi-component program. Sensitivity analysis based on risk of bias concerns did not change results. This review demonstrates that resistance training improves walking capacity, strength and walking speed in community-dwelling older adults and may facilitate aging in place. Since improvements in strength and gait speed contribute to independence, our results indicate highly beneficial outcomes for older persons.

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Analysis of Prolactin and Kappa-Casein Genes Polymorphism in Four Cattle Breeds in Turkey

Annals of Animal Science ◽

10.2478/aoas-2014-0036 ◽

2014 ◽

Vol 14 (4) ◽

pp. 799-806

Author(s):

Bilal Akyüz ◽

Mehmet Ulaş Çınar

Keyword(s):

Restriction Enzymes ◽

Chi Square ◽

Brown Swiss ◽

Weinberg Equilibrium ◽

Cattle Breeds ◽

Genotype Frequencies ◽

Pcr Rflp ◽

Chi Square Test ◽

Hardy Weinberg Equilibrium ◽

Casein Genes

Abstract The objective of this study was to identify allele and genotype frequencies of CSN3 and PRL genes in four cattle breeds in Turkey. For this purpose, a total of 390 cattle of East Anatolian Red (EAR), Zavot, Brown Swiss (BS) and Simmental (SIM) breeds were genotyped by PCR-RFLP method. A 443 bp fragment of CSN3 and a 156 bp fragment of PRL were amplified and digested with HindIII and RsaI restriction enzymes, respectively. For CSN3 and PRL genes, two types of alleles (A and B) and three types of genotypes (AA, BB, and AB) were observed. The highest frequencies for CSN3-A and CSN3-B alleles were estimated for the EAR breed (0.743) and for the BS breed (0.556), respectively. The highest frequency for PRL-A and PRL-B alleles was estimated for the SIM breed (0.801) and for the BS breed (0.315), respectively. The Chi-square test among the investigated cattle breeds showed that only the Zavot breed was in Hardy-Weinberg equilibrium (HWE) for both loci.

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