Transverse forces in skeletal muscle with massage-like loading in a rabbit model.

BACKGROUND: The objective of this study was to quantify the transverse forces in skeletal muscle subjected to constant compressive massage-like loading (MLL) following eccentric exercise (ECC). METHODS: Twenty-eight New Zealand White rabbits were used for this two-part study. For all testing, a customized electromechanical device was utilized to apply a constant compressive force MLL to the tibialis anterior (TA) muscle and the resultant transverse forces were quantified. The device consisted of two stepper motors that were positioned orthogonally to each other and connected to separate sliding tracks. A stainless steel cylindrical massage tip was mounted to a customized two-axis sensor consisting of two strain gauges with which forces along the two axes were measured. First, we determined the effects of tissue loading frequency and compression magnitude on transverse forces in the TA. Following a bout of ECC, sixteen rabbits were randomly assigned to a protocol with MLL frequency of 0.25 Hz or 0.5 Hz at a constant compressive force of 5 N or 10 N. Secondly, we utilized a protocol of 0.5 Hz, 10 N, 15 min MLL that was performed on 4 consecutive days commencing immediately post ECC (n = 6 animals) or 48 hours following ECC (n = 6 animals). Transverse forces were measured during all 4 MLL sessions for the entire 15 min duration for both the immediate and the delayed groups. RESULTS: Both frequency and magnitude of compressive force due to MLL showed an effect on the magnitude of transverse force (p < 0.05 for each parameter). Furthermore, MLL beginning immediately following ECC produced higher transverse forces than MLL delayed by 48 hours with an average 20% difference between the two MLL groups over the four day protocol. Forces were higher in the middle 5 minutes compared to the first 5 minutes for all MLL bouts in both groups. CONCLUSIONS: Frequency and magnitude of MLL and timing for delivery of MLL following ECC affect resultant transverse force values for exercised muscle. The application of our findings to humans receiving massage following exercise remains unknown at this time.

Area Deprivation Index and Distress Community Index Scores Are Not Associated With Short-Term and Long-Term Extracorporeal Life Support Outcomes.

Distressed Communities Index (DCI) and Area Deprivation Index (ADI) are two composite ranking scores that report community level socioeconomic status (SES) by ZIP codes. The objective of this study was to evaluate the impact of SES as estimated by DCI and ADI scores on short-term and long-term outcomes after extracorporeal life support (ECLS) at a quaternary medical center. All patients on ECLS between January 1, 2015 and August 31, 2020 (N = 428) at Vanderbilt University Medical Center in Nashville, Tennessee, had their ADI and DCI scores calculated. Primary outcome was mortality during index hospitalization, and secondary outcome was survival to end of study follow-up. There was no significant difference in primary outcome between the top 25% ADI vs . bottom 75% ADI (53.8% vs . 50.6%; p = 0.56) or between top 25% DCI vs . bottom 75% DCI (56.1 vs . 49.2; p = 0.21). Adjusted odds ratio for the primary outcome with ADI and DCI was 1.13 (95% CI, 0.63-2.0; p = 0.67) and 1.28 (95% CI, 0.70-2.34; p = 0.41), respectively. Additionally, there was no significant difference in long-term survival curves based on their ADI or DCI scores. In conclusion, SES as estimated by baseline DCI and ADI scores does not appear to impact short- or long-term survival post-ECLS at a large volume center. http://links.lww.com/ASAIO/A951.

Reporting of Cardiovascular Events in Clinical Trials Supporting FDA Approval of Contemporary Cancer Therapies.

BACKGROUND: Cardiovascular disease (CVD) has become an increasingly common limitation to effective anticancer therapy. Yet, whether CVD events were consistently reported in pivotal trials supporting contemporary anticancer drugs is unknown. OBJECTIVES: The authors sought to evaluate the incidence, consistency, and nature of CVD event reporting in cancer drug trials. METHODS: From the Drugs@FDA, clinicaltrials.gov, MEDLINE, and publicly available U.S. Food and Drug Administration (FDA) drug reviews, all reported CVD events across latter-phase (II and III) trials supporting FDA approval of anticancer drugs from 1998 to 2018 were evaluated. The primary outcome was the report of major adverse cardiovascular events (MACE), defined as incident myocardial infarction, stroke, heart failure, coronary revascularization, atrial fibrillation, or CVD death, irrespective of treatment arm. The secondary outcome was report of any CVD event. Pooled reported annualized incidence rates of MACE in those without baseline CVD were compared with reported large contemporary population rates using relative risks. Population risk differences for MACE were estimated. Differences in drug efficacy using pooled binary endpoint hazard ratios on the basis of the presence or absence of reported CVD were also assessed. RESULTS: Overall, there were 189 trials, evaluating 123 drugs, enrolling 97,365 participants (58.5 ± 5 years, 46.0% female, 72.5% on biologic, targeted, or immune-based therapies) with 148,138 person-years of follow-up. Over a median follow-up of 30 months, 1,148 incidents of MACE (375 heart failure, 253 myocardial infarction, 180 strokes, 65 atrial fibrillation, 29 revascularizations, and 246 CVD deaths; 792 in the intervention vs. 356 in the control arm; p < 0.01) were reported from the 62.4% of trials noting any CVD. The overall weighted-average incidence was 542 events per 100,000 person-years (716 per 100,000 in the intervention arm), compared with 1,408 among similar-aged non-cancer trial subjects (relative risk: 0.38; p < 0.01), translating into a risk difference of 866. There was no association between reporting CVD events and drug efficacy (hazard ratio: 0.68 vs. 0.67; p = 0.22). CONCLUSIONS: Among pivotal clinical trials linked to contemporary FDA-approved cancer drugs, reported CVD event rates trail expected population rates.

Effects of alcohol exposure during development on play behavior and c-Fos expression in response to play behavior.

Developmental exposure to alcohol can produce characteristic physiological and cognitive deficits, often termed Fetal Alcohol Spectrum Disorder (FASD). More recently, social deficits have been shown to occur both in FASD and animal models of FASD; the behavioral and neural bases of these deficits remain to be determined. It was hypothesized that changes in sensory processing may in part underlie the social deficits seen in FASD. This study used a rat model of FASD and social play, a behavior critical to adult social functioning, to begin to examine this hypothesis. Somatosensory cues from dorsal contact to the nape of the neck, critical to the initiation of pinning, were systematically degraded by administration of different doses of xylocaine, a topical anesthetic. Neuronal activity after 1h of play was assessed by measurement of c-Fos immunoreactivity (IR) in different brain regions. Ethanol-exposed rats showed an increased frequency of pinning during social play and were more sensitive to the degradation of somatosensory cues compared to the control groups, suggesting difficulties in processing somatosensory cues. Neuronal activity in the somatosensory cortex induced by play was significantly decreased in the ethanol-exposed group compared to the non-treated group. The c-Fos IR in the nucleus accumbens was altered in a sexually dimorphic manner in the ethanol-exposed group. Thus, the behavioral and brain measures are consistent with the hypothesis that ethanol exposure during development induces alterations in social play via deficits in processing somatosensory cues that are important to social play.