Age-related reductions in the number of serial sarcomeres contribute to shorter fascicle lengths but not elevated passive tension.

We investigated age-related changes to fascicle length, sarcomere length and serial sarcomere number (SSN), and how this affects passive force. Following mechanical testing to determine passive force, the medial gastrocnemius muscle of young (n=9) and old (n=8) Fisher 344BN hybrid rats was chemically fixed at the optimal muscle length for force production; individual fascicles were dissected for length measurement, and laser diffraction was used to assess sarcomere length. Old rats had ∼14% shorter fascicle lengths than young rats, which was driven by a ∼10% reduction in SSN, with no difference in sarcomere length (∼4%). Passive force was greater in the old than in the young rats at long muscle lengths. Shorter fascicle lengths and reduced SSN in the old rats could not entirely explain increased passive forces for absolute length changes, owing to a slight reduction in sarcomere length in old rats, resulting in similar sarcomere length at long muscle lengths.

The development and evaluation of a novel Internet-based computer program to assess previous-day dietary and physical activity behaviours in adults: the Synchronised Nutrition and Activity Program for Adults (SNAPA™).

The Synchronised Nutrition and Activity Program for Adults (SNAPA™) was developed to address the need for accurate, reliable, feasible, inexpensive and low-burden methods for assessing specific dietary and physical activity behaviours in adults. Short-term test-retest reliability of SNAPA™ was assessed in forty-four adults (age 41·4 (SD17·3) years) who completed SNAPA™ twice in 1 day. Concurrent validity against direct dietary observation and combined heart rate and accelerometry was assessed in seventy-seven adults (age 34·4 (SD11·1) years). Test-retest reliability revealed no substantial systematic shifts in mean values of the outcome variables: percentage of food energy from fat (% fat), number of portions of fruit and vegetables (FV) and minutes of moderate-to-vigorous physical activity (MVPA). For lunchtime dietary intake, the mean match rate between food items reported using SNAPA™ and those observed was 81·7%, with a phantom rate of 5·6%. Pearson's correlations between SNAPA™ and the reference methods ranged from 0·27 to 0·56 for % fat, FV portions and minutes of MVPA. For % fat and FV intake, there was no fixed or proportional bias, and mean differences between the methods (SNAPA™ - reference) were 5·1% and 0 portions, respectively. For minutes of MVPA, a fixed bias of - 28 min was revealed when compared with all minutes of MVPA measured by combined heart rate and accelerometry, whereas a proportional bias (slope 1·47) was revealed when compared with minutes carried out in bouts ≥ 10 min. SNAPA™ is a promising tool for measuring specific energy balance behaviours, though further work is required to improve accuracy for physical activity behaviours.

Effectiveness of intravenous prostaglandin to reduce digital amputations from frostbite: an observational study.

PURPOSE: We assessed the effectiveness and safety of a 5-day intravenous prostaglandin (iloprost) protocol at reducing digital amputation for patients with severe frostbite injuries at urban emergency departments. METHODS: This retrospective study examines consecutive patients who presented to Calgary emergency departments from April 2017 to April 2020 with Grade 2-4 frostbite injuries. Patients from February 2019 onward were managed using a 5-day iloprost infusion protocol, whereas patients prior to this time were managed with standard care (local best practice without iloprost as a therapeutic option). The primary effectiveness outcome was rate of affected digits amputated, stratified by frostbite severity. The secondary safety outcome was the incidence of serious adverse events associated with iloprost (allergic reactions or symptomatic hypotension requiring treatment or discontinuation of the infusion). RESULTS: 90 patients were included, 26 were treated with iloprost, compared to 64 patients who received usual care. Both the treatment and usual care groups experienced substantial rates of homelessness and substance use. No digital amputations were required for patients with Grade 2 injuries in either group, but significantly lower digital amputation rates were observed for patients with more severe frostbite injuries treated with iloprost versus usual care: Grade 3 (18% vs 44%, p < 0.001), Grade 4 (46% vs 95%, p < 0.001). No serious adverse events were associated with iloprost. CONCLUSION: In this unselected socially complex urban population, administration of iloprost for patients with frostbite was shown to be safe and was associated with lower digital amputation rates, particularly for those with more severe injuries.

RéSUMé: OBJECTIF: Nous avons évalué l'efficacité et la sécurité d'un protocole de 5 jours de prostaglandine intraveineuse (iloprost) pour réduire l'amputation digitale chez les patients souffrant d'engelures graves dans les services d'urgence urbains. MéTHODES: Cette étude rétrospective examine des patients consécutifs qui se sont présentés aux services d'urgence de Calgary d'avril 2017 à avril 2020 avec des engelures de niveau 2 à 4. À compter de février 2019, les patients ont été traités au moyen d'un protocole de perfusion d'iloprost de 5 jours, tandis que les patients avant cette période ont été pris en charge avec des soins standard (meilleures pratiques locales sans iloprost comme option thérapeutique). Le principal résultat d'efficacité était le taux de doigts affectés amputés, stratifié selon la gravité des gelures. Le critère secondaire de sécurité était l'incidence des événements indésirables graves associés à l'iloprost (réactions allergiques ou hypotension symptomatique nécessitant un traitement ou l'arrêt de la perfusion). RéSULTATS: 90 patients ont été inclus, 26 ont été traités avec de l'iloprost, contre 64 patients qui ont reçu les soins habituels. Les groupes de traitement et de soins habituels ont tous deux connu des taux importants de sans-abrisme et de consommation de substances. Aucune amputation digitale n'a été nécessaire pour les patients présentant des lésions de grade 2 dans l'un ou l'autre groupe, mais des taux d'amputation digitale significativement plus faibles ont été observés pour les patients présentant des lésions de gelures plus sévères traités par iloprost par rapport aux soins habituels : Grade 3 (18 % contre 44 %, p < 0,001), Grade 4 (46 % contre 95 %, p < 0,001). Aucun événement indésirable grave n'a été associé à l'iloprost. CONCLUSION: Dans cette population urbaine non sélectionnée et socialement complexe, l'administration d'iloprost pour les patients souffrant d'engelures s'est avérée sûre et a été associée à des taux d'amputation digitale plus faibles, en particulier pour ceux présentant des blessures plus graves.

The development and evaluation of a novel computer program to assess previous-day dietary and physical activity behaviours in school children: the Synchronised Nutrition and Activity Program (SNAP).

Self-report recall questionnaires used to measure physical activity and dietary intake in children can be labour intensive and monotonous and tend to focus on either dietary intake or physical activity. The web-based software, Synchronised Nutrition and Activity Program (SNAP), was developed to produce a novel, simple, quick and engaging method of assessing energy balance-related behaviours at a population level, combining principles from new and existing 24 h recall methodologies, set within a user-friendly interface. Dietary intake was measured using counts for twenty-one food groups and physical activity levels were measured in min of moderate to vigorous physical activity (MVPA). A combination of the mean difference between methods, type II regression and non-parametric limits of agreement techniques were used to examine the accuracy and precision of SNAP. Method comparison analyses demonstrated a good agreement for both dietary intake and physical activity behaviours. For dietary variables, accuracy of SNAP (mean difference) was within +/- 1 count for the majority of food groups. The proportion of the sample with between-method agreement within +/- 1 count ranged from 0.40 to 0.99. For min of MVPA, there was no substantial fixed or proportional bias, and a mean difference between methods (SNAP - accelerometry) of -9 min. SNAP provides a quick, accurate, low-burden, cost-effective and engaging method of assessing energy balance behaviours at a population level. Tools such as SNAP, which exploit the popularity, privacy and engagement of the computer interface, and linkages with other datasets, could make a substantial contribution to future public health monitoring and research.

Prevalence of pulmonary embolism in syncope patients.

Clinical questionHow often is pulmonary embolism (PE) found in patients admitted for syncope?Article chosenPrandoni P, Lensing A, Prins M, et al. Prevalence of pulmonary embolism among patients hospitalized for syncope (PESIT). N Engl J Med 2016;375:1524-31, doi: 10.1056/NEJMoa1602172. OBJECTIVE: To determine the prevalence of PE in patients hospitalized for a first episode of syncope.

Development and evaluation of a novel computer-based tool for assessing physical activity levels in schoolchildren.

A novel computer tool (peas@tees), designed to assess habitual physical activity levels in children aged 9 and 10 years, was evaluated. Study 1 investigated agreement between peas@tees and accelerometry in 157 children. Bland-Altman limits of agreement (LOA) revealed peas@tees underestimated physical activity levels compared with accelerometry (bias -21 min; 95% LOA -146-105). Study 2 investigated stability of peas @ tees in a separate sample of 42 children. Intraclass correlation coefficient was 0.75 (95% CI 0.62-0.84). Computer tools are promising as a cheap, feasible, and useful method to monitor children's habitual levels of physical activity at the group level.