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Sex differences in the influence of body mass index on anatomical architecture of brain networks.
Background/objectivesThe brain has a central role in regulating ingestive behavior in obesity. Analogous to addiction behaviors, an imbalance in the processing of rewarding and salient stimuli results in maladaptive eating behaviors that override homeostatic needs. We performed network analysis based on graph theory to examine the association between body mass index (BMI) and network measures of integrity, information flow and global communication (centrality) in reward, salience and sensorimotor regions and to identify sex-related differences in these parameters.Subjects/methodsStructural and diffusion tensor imaging were obtained in a sample of 124 individuals (61 males and 63 females). Graph theory was applied to calculate anatomical network properties (centrality) for regions of the reward, salience and sensorimotor networks. General linear models with linear contrasts were performed to test for BMI and sex-related differences in measures of centrality, while controlling for age.ResultsIn both males and females, individuals with high BMI (obese and overweight) had greater anatomical centrality (greater connectivity) of reward (putamen) and salience (anterior insula) network regions. Sex differences were observed both in individuals with normal and elevated BMI. In individuals with high BMI, females compared to males showed greater centrality in reward (amygdala, hippocampus and nucleus accumbens) and salience (anterior mid-cingulate cortex) regions, while males compared to females had greater centrality in reward (putamen) and sensorimotor (posterior insula) regions.ConclusionsIn individuals with increased BMI, reward, salience and sensorimotor network regions are susceptible to topological restructuring in a sex-related manner. These findings highlight the influence of these regions on integrative processing of food-related stimuli and increased ingestive behavior in obesity, or in the influence of hedonic ingestion on brain topological restructuring. The observed sex differences emphasize the importance of considering sex differences in obesity pathophysiology
Pathology of chronic achilles-tendon injuries in athletes
Overuse tendon conditions have traditionally been considered to result from an inflammatory process and were treated as such. Microscopic examination of abnormal Achilles-tendon tissues, however, reveals a non-inflammatory degenerative process. The histopathology found in surgical specimens in patients with chronic overuse Achilles tendinopathy and those with Achilles-tendon rupture are reviewed. Seminal studies suggest that so-called tendinitis is a rare condition that might occur occasionally in the Achilles tendon in association with a primary tendinosis. These data have clinical implications and require a review of the traditional classification of pathologies seen in tendon conditions, The authors recommend that nomenclature be based on histopathological findings rather than traditional hypothesis. <br /
“everything in one place”
Purpose: To describe older adults’ perspectives on a new patient education
manual for the recovery process after hip fracture. Materials and methods: The
Fracture Recovery for Seniors at Home (FReSH) Start manual is an evidence-
based manual for older adults with fall-related hip fracture. The manual aims
to support the transition from hospital to home by facilitating self-
management of the recovery process. We enrolled 31 community-dwelling older
adults with previous fall-related hip fracture and one family member. We
collected data using a telephone-based questionnaire with eight five-point
Likert items and four semi-structured open-ended questions to explore
participants’ perceptions on the structure, content, and illustration of the
manual. The questionnaire also asked participants to rate the overall utility
(out of 10 points) and length of the manual. We used content analysis to
describe main themes from responses to the open-ended interview questions.
Results: Participants’ ratings for structure, content, and illustrations
ranged from 4 to 5 (agree to highly agree), and the median usefulness rating
was 9 (10th percentile: 7, 90th percentile: 10). Main themes from the content
analysis included: ease of use and presentation; health literacy; illustration
utility; health care team delivery; general impression, information support
from hospital to home; emotional and decision-making support; and the novelty
of the manual. Conclusion: The FReSH Start manual was perceived as
comprehensive in content and acceptable for use with older adults post-fall-
related hip fracture. Participants expressed a need for delivery and
explanation of the manual by a health care team member
Older Adults’ Outdoor Walking and the Built Environment: Does Income Matter?
Background
Our aim was to examine the association between Street Smart Walk Score® and self-reported outdoor walking among older Canadians, and to determine whether socioeconomic status modifies this association.
Methods
We linked objective walkability data with cross-sectional survey data from the Canadian Community Health Survey Healthy-Aging 2008–2009 Cycle for a sample of 1309 British Columbians aged ≥ 65 years. We examined associations between Street Smart Walk Score and meeting physical activity guidelines (≥150 min of moderate to vigorous activity/week) through self-reported outdoor walking using multivariable logistic regression, and tested for significant interactions with household income.
Results
A ten point higher Street Smart Walk Score was associated with a 17 % higher odds of meeting physical activity guidelines through walking outside (95 % CI: 1.07,1.27). In addition, older adults living in neighbourhoods categorised as Walker’s Paradise were over three times more likely to meet guidelines than those living in Car-dependent/Very car dependent neighbourhoods. We found no evidence that household income moderated the effect of Walk Score on walking outside.
Conclusions
Neighbourhood design may be one avenue whereby physical activity levels of older people can be enhanced through outdoor walking, with benefit across socioeconomic strata
a pilot randomized controlled trial
Objectives: Our primary aim of this pilot study was to test feasibility of the
planned design, the interventions (education plus telephone coaching), and the
outcome measures, and to facilitate a power calculation for a future
randomized controlled trial to improve adherence to recovery goals following
hip fracture. Design: This is a parallel 1:1 randomized controlled feasibility
study. Setting: The study was conducted in a teaching hospital in Vancouver,
BC, Canada. Participants: Participants were community-dwelling adults over 60
years of age with a recent hip fracture. They were recruited and assessed in
hospital, and then randomized after hospital discharge to the intervention or
control group by a web-based randomization service. Treatment allocation was
concealed to the investigators, measurement team, and data entry assistants
and analysts. Participants and the research physiotherapist were aware of
treatment allocation. Intervention: Intervention included usual care for hip
fracture plus a 1-hour in-hospital educational session using a patient-
centered educational manual and four videos, and up to five postdischarge
telephone calls from a physiotherapist to provide recovery coaching. The
control group received usual care plus a 1-hour in-hospital educational
session using the educational manual and videos. Measurement: Our primary
outcome was feasibility, specifically recruitment and retention of
participants. We also collected selected health outcomes, including health-
related quality of life (EQ5D-5L), gait speed, and psychosocial factors
(ICEpop CAPability measure for Older people and the Hospital Anxiety and
Depression Scale). Results: Our pilot study results indicate that it is
feasible to recruit, retain, and provide follow-up telephone coaching to older
adults after hip fracture. We enrolled 30 older adults (mean age 81.5 years;
range 61–97 years), representing a 42% recruitment rate. Participants excluded
were those who were not community dwelling on admission, were discharged to a
residential care facility, had physician-diagnosed dementia, and/or had
medical contraindications to participation. There were 27 participants who
completed the study: eleven in the intervention group, 15 in the control
group, and one participant completed a qualitative interview only. There were
no differences between groups for health measures. Conclusion: We highlight
the feasibility of telephone coaching for older adults after hip fracture to
improve adherence to mobility recovery goals
Linked Lives: Exploring Gender and Sedentary Behaviors in Older Adult Couples
Objectives: We explored associations between co-habiting partners for sedentary behavior (type and time, via accelerometry and self-report), gender, and a surrogate health measure (inflammatory biomarker: C-reactive protein, CRP). Methods: Participants completed activity questionnaires and the Timed Up and Go (mobility), wore an accelerometer for 7 days, and provided samples for high-sensitivity (hs) CRP. We used multilevel modeling (partners within couples) to investigate associations between independent variables and (a) sedentary behavior and (b) hsCRP. Results: 112 couples (50% women) provided sedentary data and hsCRP. Sedentary behavior was significantly correlated (r = .440, p men). Gender, moderate to vigorous physical activity (MVPA), and mobility estimated 37% of the modeled variance in sedentary time, while body mass index (BMI) and MVPA estimated 10% of the modeled variance in hsCRP. Discussion: Despite differences in how activity was accumulated, there were no significant differences between women’s and men’s health biomarker.Canadian Institutes of Health Research
https://doi.org/10.13039/501100000024michael smith foundation for health research
https://doi.org/10.13039/501100000245social sciences and humanities research council of canada
https://doi.org/10.13039/501100000155university of british columbia
https://doi.org/10.13039/501100005247Peer Reviewe
Daily Affect and Daily Prospective Memory in People after Stroke and Their Partners: The Moderating Role of Resting Heart Rate
Introduction: Experimental research suggests that affect may influence prospective memory performance, but real-life evidence on affect-prospective memory associations is limited. Moreover, most studies have examined the valence dimension of affect in understanding the influence of affect on cognitive performance in daily life, with insufficient consideration of the arousal dimension. To maximize ecological validity, the current study examined the relationships between daily affect and daily prospective memory using repeated daily assessments and the role of resting heart rate on these relationships. We examined both valence and arousal of daily affect by categorizing affect into four dimensions: high-arousal positive affect, low-arousal positive affect, high-arousal negative affect, and low-arousal negative affect. Method: We examined existing data collected from community-dwelling couples, of which at least one partner had a stroke history. The analytic sample included 111 adults (Mage = 67.46 years, SD = 9.64; 50% women) who provided 1,274 days of data. Among the participants, 58 were living with the effects of a stroke and 53 were partners. Participants completed daily event-based prospective memory tasks (in morning and/or evening questionnaires), reported daily affect in the evening, and wore a wrist-based Fitbit device to monitor resting heart rate over 14 consecutive days. Results: Results from multilevel models show that, within persons, elevated high-arousal negative affect was associated with worse daily prospective memory performance. In addition, lower resting heart rate attenuated the inverse association between high-arousal negative affect and lowered prospective memory performance. We did not find significant associations of high- or low-arousal positive affect and low-arousal negative affect with daily prospective memory. Discussion: Our findings are in line with the resource allocation model and the cue-utilization hypothesis in that high-arousal negative affect is detrimental to daily prospective memory performance. Lower resting heart rate may buffer individuals’ prospective memory performance from the influence of high-arousal negative affect. These findings are consistent with the neurovisceral integration model on heart-brain connections, highlighting the possibility that cardiovascular fitness may help maintain prospective memory into older adulthood
Selective prebiotic synthesis ofphosphoroaminonitriles and aminothioamides inneutral water
The central and conserved role of peptides in extant biology suggests that they played animportant role during the origins of life. Strecker amino acid synthesis appears to be prebiotic,but the high pKaHof ammonia (pKaH=9.2) necessitates high pH reaction conditions torealise efficient synthesis, which places difficult environmental constraints on prebiotic aminoacid synthesis. Here we demonstrate that diamidophosphate reacts efficiently with simplealdehydes and hydrogen cyanide in water at neutral pH to affordN-phosphoro-aminonitriles.N-Phosphoro-aminonitrile synthesis is highly selective for aldehydes; ketones give poorconversion.N-Phosphoro-aminonitriles react with hydrogen sulfide at neutral pH to furnishaminothioamides. The high yield (73%–Quant.) of N-phosphoro-aminonitriles at neutral pH, and their selective transformations, may provide new insights into prebiotic amino acid synthesis and activation
EIT of the Human Body with Optimal Current Patterns and Skin-Electrode Impedance Compensation
Following the lead of the EIT research group at Rensselaer Polytechnic Institute, we have designed and implemented a system comprising 32 independent current sources, in which it is possible to apply current patterns optimizing distinguishability. One potential technical problem is that we are measuring voltages on current-carrying electrodes, giving some sensitivity to time varying skinelectrode impedances. We demonstrate here an algorithm to estimate simultaneously changes in the medium and timevarying skin-electrode impedances
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