Lower Body Research Articles

Transcriptome profile of sex-related gene expression and effects of cyp19a1 siRNA-silencing on sex differentiation and determination in yellow perch

In this study, we first sequenced the whole genome of the yellow perch (YP, Perca favencens) and screened transcripts of brain, liver, and gonadal tissues from fish of different sexes. By comparing known female sex-related genes in fish such as cyp19a1 and dmrt1 with YP genome, we obtained full-length sequences through genomic homology analysis. Then an experiment was conducted to evaluate the effects of cyp19a1-siRNA interference on gonadal development and sex differentiation and determination in YP. Transcriptome analysis revealed that the gonadal tissue of female YP exhibited predominantly and differentially up-regulated expression of genes than males, and cyp19a1 was predominantly expressed in the gonads while cyp19a2 showed predominant expression in the brain. KEGG pathway enrichment analysis illustrated the metabolic pathways of the top 25 enriched genes and confirmed CYP19 (P450) pathway in YP. For the cyp19a1-siRNA interference experiment, four intermittent in vivo injections of siRNA were administered to interfere with cyp19a1 gene expression in an all-female group of YP. The results collected at 180 dph revealed that the siRNA interference resulted in an incomplete masculinization and hermaphroditism of all-female monosex YP, displaying the presence of male spermatocytes along with female oocytes. In contrast, tissues from the blank control and negative control groups only contained oocytes. The appearance of the gonads in the experimental group appeared more irregular, lacking the smooth surface and typical histoarchitecture observed in the blank control and negative control groups. In addition, the cyp19a1-siRNA treatment group had significantly (P < 0.05) lower body weight than the control groups, indicating that the interference with cyp19a1 might have affected the expression of estrogen, leading to a trend similar to the growth of males; similarly, the gonad weight and GSIs of the cyp19a1 group were significantly (P < 0.05) lower than those in the control groups, suggesting that the cyp19a1-siRNA interference might have led to a trend of male type of gonadal development. Meanwhile, the treatment group had significantly (P < 0.05) higher HSI and VSI levels compared to control groups, indicating that stimulation of external siRNA might have resulted in more vigorous liver metabolism processes. Furthermore, the expression level of the dmrt1 in the treatment group was significantly (P < 0.05) upregulated compared to the control groups, suggesting the correlation roles between these two genes in the regulation of sex development. The findings provide valuable insights for future research into the underlying mechanisms involved and hold significant promise for sex control in aquaculture.

On growth and scoliosis

PurposeTo describe the physiology of spinal growth in patients with adolescent idiopathic scoliosis (AIS).MethodsNarrative review of the literature with a focus on mechanisms of growth.ResultsIn his landmark publication On Growth and Form, D’Arcy Thompson wrote that the anatomy of an organism reflects the forces it is subjected to. This means that mechanical forces underlie the shape of tissues, organs and organisms, whether healthy or diseased. AIS is called idiopathic because the underlying cause of the deformation is unknown, although many factors are associated. Eventually, however, any deformity is due to mechanical forces. It has long been shown that the typical curvature and rotation of the scoliotic spine could result from vertebrae and intervertebral discs growing faster than the ligaments attached to them. This raises the question why in AIS the ligaments do not keep up with the speed of spinal growth. The spine of an AIS patient deviates from healthy spines in various ways. Growth is later but faster, resulting in higher vertebrae and intervertebral discs. Vertebral bone density is lower, which suggests less spinal compression. This also preserves the notochordal cells and the swelling pressure in the nucleus pulposus. Less spinal compression is due to limited muscular activity, and low muscle mass indeed underlies the lower body mass index (BMI) in AIS patients. Thus, AIS spines grow faster because there is less spinal compression that counteracts the force of growth (Hueter–Volkmann Law). Ligaments consist of collagen fibres that grow by tension, fibrillar sliding and the remodelling of cross-links. Growth and remodelling are enhanced by dynamic loading and by hormones like estrogen. However, they are opposed by static loading.ConclusionIncreased spinal elongation and reduced ligamental growth result in differential strain and a vicious circle of scoliotic deformation. Recognising the physical and biological cues that contribute to differential growth allows earlier diagnosis of AIS and prevention in children at risk.

283 Identification of new or existing risk factors associated with the development of sow pelvic organ prolapse

Abstract A survey was conducted between March and December of 2022 to examine the variation between farms that had high and low pelvic organ prolapse (POP) rate. The objective was to identify new or existing risk factors associated with the development of POP, which could open new avenues for further investigation. Sow farms (n = 53) across 26 production systems located in the US, Canada, and Mexico were used. Sampling of farms was not random. High and low POP systems were selected within each region as well as high and low POP farms within each system. Over 800 variables related to general farm information and management, performance traits, reproductive management, replacement gilt management, gestation and farrowing practices, labor and health management, and nutrition were collected during farm visits. To be included in the analysis, at least 70% of observations were needed for continuous variables with at least 10% of observation for each category for categorical variables. Univariable models were fitted to identify variables associated with annualized POP rate for 2021. Variables with P ≤ 0.10 were selected for further analysis, with 94 predictor variables selected for principal components analysis (PCA). A factor analysis of mixed data was conducted, and results were then fitted into a hierarchical clustering on PCA, which segregated the data into three clusters: 2 with low POP (2.5%) and 1 with high POP (6.1%) prevalence (low vs high P &amp;lt; 0.05). The resulting clusters explained 33.7% of the variability in annualized 2021 POP rate. Differences between clusters were evaluated by Kruskall-Wallis test for numerical variables and chi-square test for categorical variables. High POP cluster farms had greater total piglets born over the years, greater number of sows per worker, greater annual gestation feed usage, and a lower mean body condition score at 16 wk of gestation compared with low POP cluster farms. High POP cluster farms had a decreased proportion of farms using conventional artificial insemination, a greater proportion of farms utilizing cup waterers in gestation for sows in group housing and in farrowing, and greater proportion of farms with a routine sleeving practice. High POP cluster farms compared with low POP cluster farms had greater gestation distillers dried grains with solubles (DDGS) inclusion level (14.6% vs 4.0%, SE 3.02), greater levels of standardized total tract digestibility (STTD) P% (0.49% vs 0.39%, SE 0.014), narrower analyzed Ca to STTD P ratio (1.7 vs 2.2, SE 0.06), and lower phytase inclusion and release (0.16% vs 0.09%, SE 0.014). These variables were also the predictors with the greatest R2 values in the univariable models. These observations suggest further research is needed to evaluate the connection between dietary Ca and P and pelvic organ prolapse.

96 Evaluating the impact of macroenvironment temperature on thermoregulatory and milk quality parameters in lactating sows and their litter

Abstract Farrowing facility macroenvironment temperatures (TMacro) are often maintained at the upper end of the thermoneutral zone (24–25°C) of lactating sows, which may result in heat stress and reduced milk quality and quantity. Therefore, the study objective was to evaluate the impact of TMacro on thermoregulatory and milk quality parameters in lactating sows and their litters. In two repetitions, 37 lactating sows (parity = 3.1 ± 1.7) and their litters (d 1 litter size = 12.0 ± 1.0) were housed within 1 of 3 farrowing rooms set to different TMacro: LOW (n = 12 sows and litters; 15.0 ± 0.4°C), MID (n = 13 sows and litters; 19.3 ± 0.2°C), and HIGH (n = 12 sows and litters; 24.6 ± 0.8°C). Lactating sows and litters were monitored from d 3 of lactation until weaning (19.8 ± 0.9 d of age). All litters were provided with a 0.34 × 1.52 m heating pad. Sow respiration rates (RR, breaths per minute, BPM) were measured daily at 0800, 1200, 1600 and 2000 h by counting the number of flank movements. Vaginal temperature (TV) was measured in all sows at 10-min intervals using implanted data loggers. One sentinel piglet from each litter was implanted with a temperature recording bolus at d 2 of age to monitor core body temperature in 15-min intervals. Milk samples were collected from all sows on d 6, 12, and 18 of lactation and analyzed for true protein %, total solid %, and fat %. Data were analyzed using PROC GLIMMIX. The litter was considered the experimental unit for piglet measures, and the sow was considered the experimental unit for sow measures. Respiration rates were greater (P &amp;lt; 0.01) for HIGH (48 ± 2 bpm) sows versus MID (33 ± 2 BPM) and LOW (27 ± 2 bpm) sows, but no differences were detected between MID and LOW sows. A TMacro treatment by lactation day effect was observed for TV (P = 0.02), where HOT sows had greater TV on lactation d 15 (+0.31°C), 18 (+0.43°C) and 19 (+0.34°C) versus MID and LOW sows. Piglet core body temperature was reduced (P &amp;lt; 0.01) in the HIGH (39.07 ± 0.06 °C) versus the MID (39.31 ± 0.06 °C) and LOW (39.33 ± 0.07 °C) treatment groups, but it was similar for MID and LOW litters. Fat % was reduced for COLD (6.15 ± 0.52%) versus MID (7.35 ± 0.50%) sows on d 12, but no differences were observed when compared with HIGH sows (6.97 ± 0.52%). In conclusion, the HIGH treatment resulted in physiological heat stress for lactating sows and lowered piglet core body temperature, but it had minimal effects on measures of milk quality.

PSI-8 Impact of feeding level on boars from selection to entering the boar stud on trainability and growth measurements

Abstract The objective of this study was to determine if restricting feed in boars at selection impacts growth of boars or training for semen collection. Duroc boars (n = 25) randomly allotted at 6 mo of age to receive one of two levels of restricted feeding (1.8 kg/d, n = 12 or 2.72 kg/d, n = 13) of a corn-soybean meal-based diet formulated to meet NRC (2012) requirements. Diets were fed for 9 wk before training for semen collection where body weight (BW), body condition score (BCS), flank-flank tape measurements, Knauer sow caliper, loin muscle depth, backfat depth, and scrotal width and length were collected every 3 wk. Training for semen collection was conducted 5 d/wk for 2 wk. Boars were given 10 min in the collection pen to successfully mount the dummy and start collection each training session. Training was scored on a scale of 1-5, 1 = no interest and 5 = successful collection. After three successful collections in a row, boars were considered fully trained. All boars had their first production collection on wk 12. Data were analyzed using PROC MIXED and PROC FREQ chi-square in SAS 9.4 with boar serving as experimental unit. Weeks were analyzed individually and overall changes were evaluated. Significance was determined at P &amp;lt; 0.05 and a trend was observed at 0.05 &amp;lt; P ≤ 0.10. Boars fed 2.72 kg/d had increased BW on wk 9 (P &amp;lt; 0.05) and wk 12 (163.6 kg vs 149.8 kg, SE = 2.17; P &amp;lt; 0.001), increased BW gain wk 1-9 (P &amp;lt; 0.01), wk 9-12 (P &amp;lt; 0.001), and overall (49.8 kg vs 34.4 kg, SE = 1.60; P &amp;lt; 0.0001). The 2.72 kg/d boars also had increased backfat depth on wk 9 (P &amp;lt; 0.01) and wk 12 (8.4 mm vs 7.5 mm, SE = 0.17; P &amp;lt; 0.001), larger caliper scores on wk 12 (P &amp;lt; 0.01), greater flank-flank distance on wk 9 (P &amp;lt; 0.01), and increased BCS on wk 12 (3.2 vs 2.7, SE = 0.14; P &amp;lt; 0.01). No differences were observed for loin muscle depth, or scrotal width and length. Feeding level did not affect trainability with approximately 92% of boars being trained at the end of the two-week period in both feeding levels. Boars fed 2.72 kg/d had increased semen volume (128 mL vs 81 mL, SE = 12.1; P &amp;lt; 0.01) on their first production collection on wk 12 with no effects on other semen quality parameters. Overall, feeding boars 1.8 kg/d for 12 weeks following selection resulted in lower body weight and composition measures indicating limit feeding boars at selection could be used to slow growth rates, potentially decreasing structural issues, and increasing longevity of growing boars in the boar stud, with no effects on training for semen collection. Future research is needed to investigate the long-term impacts of the degree of limit feeding growing boars following selection on lifetime semen quality and quantity. Keywords boar, management, nutrition

Beak and feather disease virus detected in the endangered Red Goshawk (Erythrotriorchis radiatus)

We report the first detection and prevalence of Beak and feather disease virus (BFDV) in Australia’s Red Goshawk (Erythrotriorchis radiatus). This is a new host for this pervasive pathogen amongst a growing list of non-psittacine species including birds of prey from the orders Accipitriformes (hawks, eagles, kites), Falconiformes (falcons and caracas), and Strigiformes (owls). The Red Goshawk is the first non-psittacine species listed as Endangered to be diagnosed with BFDV. We report an initial case of infection discovered post-mortem in a dead nestling and subsequent surveillance of birds from across northern Australia. We reveal BFDV prevalence rates in a wild raptor population for the first time, with detections in 25% (n = 7/28) of Red Goshawks sampled. Prevalence appears higher in juveniles compared to adults, although not statistically significant, but is consistent with studies of wild psittacines. BFDV genotypes were associated with the Loriinae (lorikeets, budgerigar, and fig parrots), Cacatuini (Cockatoos), and Polytelini (long-tailed parrots) tribes; species which are preyed upon by Red Goshawks. A positive BFDV status may be associated with lower body mass but small sample sizes precluded robust statistical analysis. We postulate the possible impacts of the virus on Red Goshawks and discuss future research priorities given these preliminary observations.

Is axillary artery cannulation necessary in type II hybrid aortic arch repair for acute type A aortic dissection?

Axillary artery cannulation (AAC) has been widely employed in total arch replacement surgeries using the frozen elephant trunk (FET) technique for acute type A aortic dissection (ATAAD), showing better clinical results than femoral artery cannulation (FAC). Nevertheless, in type II hybrid arch repair (HAR), FAC is crucial for lower body perfusion. Hence, it is unclear whether AAC remains necessary or if AAC represents a more advantageous method for initiating cardiopulmonary bypass. We conducted a study involving patients diagnosed with ATAAD who underwent type II HAR from August 2021 to December 2022. Demographic baseline and intraoperative data were collected, and the postoperative outcomes of patients receiving FAC only were compared with those receiving AAC. There were no significant differences in baseline demographics between patients who underwent FAC alone (n = 46) and those who underwent AAC (n = 39). Patients who underwent AAC showed a lower incidence of transient neurological dysfunction (TND) post-surgery compared to those who underwent FAC (12.8% vs 32.6%, p = .032). There were no significant differences between the groups in terms of postoperative mortality within 30days, permanent neurological dysfunction (PND), length of stay in the intensive care unit (ICU) and postoperative ward, duration of mechanical ventilation, and other complications. Axillary artery cannulation may decrease the incidence of postoperative transient neurological dysfunction (TND) in type II HAR for ATAAD. Nonetheless, studies with larger sample sizes are necessary.

Chemical Composition of Newborn Piglets with Different Weights at Birth in Sows with a High Reproductive Performance.

The present study aimed to quantify and update the data on the body composition (energy nutrients) of newborn piglets of different body weights at the time of birth, as well as of the placenta mass. Data were collected from newborn piglets (n = 25) from modern genetic lines which were stillborn or died within the first 24 h of life after being crushed to death with various body weights at birth (<0.8 kg (n = 5); 0.8-1.2 kg (n = 5); >1.2-1.6 kg (common birth weight, n = 10) and >1.6 kg (n = 5)). The placenta (n = 20) of sows from a conventional breeding farm were collected, too. The body composition of newborns of "normal" (>1.2-1.6 kg) and even lighter (0.8-1.2) weights still indicated a "normal" composition. In the case of a lower body weight of piglets <0.8 kg at birth, the crude ash (24.1%) and crude protein (8.21%) contents were higher, but the crude fat (16.1%), carbohydrate (57.4%), and gross energy (3.60%) contents were lower. The placental composition in comparison to the piglet body composition was characterized by higher crude protein contents (24.3%) and lower crude ash (31.6%), crude fat (9.08%), and carbohydrate (55.6%) contents. In conclusion, the energy and protein accumulation in the total mass of fetuses and placentas increased by 75% and 64%, respectively, in comparison to times in which the litter size varied around 10-12 piglets, essentially as a result of the larger fetal mass and not of a different body composition.

Associations between temporal eating patterns and body composition in young adults: a cross-sectional study.

The aim of this study was to examine the associations between body composition and temporal eating patterns, including time of first eating occasion, time of last eating occasion, eating window, and eating jet lag (the variability in meal timing between weekdays and weekends). A total of 131 participants were included in the study. Temporal eating pattern information was collected through consecutive 7-day eat timing questionnaires and photographic food records. Body composition was assessed by bioelectrical impedance analysis. Multiple linear regression models were used to evaluate the relationships of temporal eating patterns with body composition, and age was adjusted. Eating midpoint was additionally adjusted in the analysis of eating window. On weekdays, both later first eating occasion and last eating occasion were associated with lower lean mass, and longer eating window was associated with lower body fat percentage. On weekends, both later first eating occasion and last eating occasion were associated with lower lean mass, and longer eating window was associated with higher FFMI. Longer first eating occasion jet lag was associated with lower lean mass. Our study suggested that earlier and more regular eating patterns may have a benefit on body composition.

Biomechanical effects of men’s dress shoes made with bacterial cellulosic composite

PurposeThis study aimed to compare the performance of sustainable shoes made with bacterial cellulosic composite and commercial leather shoes using an experimental research design. The two specific research objectives were: (1) to examine the basic material properties of multi-layered bacterial cellulosic materials (MBC), which include green tea-based cellulosic (GBC) mats, hemp fabrics, and denim fabrics, in comparison with those of two-layered leathers (MCP) consisting of calf-skin and pig-skin – commonly used in shoe manufacturing; and (2) to explore wearers’ performance in the two types of shoes by assessing quantitative kinematic and kinetic parameters of lower body movements.Design/methodology/approachThis study focused on assessing the basic materials testing and performance of sustainable shoes through a biomechanical approach, in contrast to commercially available leather shoes, through human wear trials. In this study, green tea-based cellulosic (GBC) mats were developed using the optimal combination of ingredients for cellulose growth. Subsequently, the GBC, denim fabric (100% cotton), and 100% hemp fabric were combined to create multi-layered bacterial cellulosic materials (MBC) as an alternative to leather. Additionally, calf-skin and pig-skin leathers were utilized to produce a commercially available two-layered leather (MCP), commonly employed in shoe manufacturing. 37 of the 42 human subjects who participated in wear testing were collected. A paired t-test was conducted to determine whether significant mean differences existed between the two shoe types, a paired t-test was conducted.FindingsTo develop a biodegradable and compostable material that could be used as a leather alternative for the footwear industry, we proposed MBC and examined its properties compared with those of MCP, a product often used when making shoes. These findings confirmed the similar properties of MBC and MCP from the material testing and the possibility of using a men’s sustainable shoe prototype as a leather alternative, in terms of kinematics and kinetics.Practical implicationsThe new multi-layered bacterial cellulosic materials (MBC) could be an alternative to commercial leathers such as innovative sustainable material construction, advanced design, and advanced techniques to optimize the overall performance of sustainable footwear.Originality/valueInvestigating the integration of smart textile technologies, ergonomic design principles, and personalized customization will contribute to developing MBC and making sustainable shoes using MBC compared with commercial leather shoes. This study provides valuable insights into further refinement and innovation in the sustainable footwear industry.

Assessing the effects of cold storage regimes of North American Bombus Gynes

AbstractBumble bees are the primary commercial pollinators for greenhouse‐grown crops and managing them requires insight into the Bombus life cycle. However, some aspects of the life cycle are not fully understood. Once mated, adult Bombus gynes can be stored for a short term at a constant low temperature (CLT). However, survival rates for some species are low during CLT, particularly when storage periods exceed a month. To address this, we tested the hypothesis that Bombus gynes stored in a fluctuating thermal regime (FTR) have increased survival compared to gynes stored in CLT. Specifically, the FTR had a baseline temperature of 2°C, with a daily fluctuation to 20°C relative to the CLT of 2°C with no warming pulse. We tested the effects of FTR on gyne survival and post‐cold storage lipid content in three species used for commercial pollination in North America: B. vosnesenskii, B. huntii and B. impatiens. We further assessed how additional factors influence cold storage survival, including gyne body weight, body size and colony age. Survival responses varied among species. Bombus vosnesenskii and B. huntii had a lower survival rate in FTR compared to CLT, but B. impatiens gynes had a significantly higher survival rate in FTR. We did not observe significant effects of FTR on lipid stores for any species, but survival increased with an increasing initial weight prior to cold storage. Moreover, gynes produced later in the colony life cycle had lower body weight and decreased survival compared to early emerging gynes. Our study provides insight into how cold storage conditions interact with colony and gyne characteristics to influence captive overwintering survival. Our findings have economic applications for improving commercial rearing and efforts for conservation rearing of at‐risk Bombus species.

Short-Term Outcomes of Transcatheter Aortic Valve Replacement in Low-Risk Patients With Pure Severe Aortic Regurgitation

Transcatheter aortic valve replacement (TAVR) has emerged as an alternative treatment for patients with pure severe aortic regurgitation (PSAR) who are contraindicated for surgery or have a high surgical risk. However, the therapeutic efficacy and safety of TAVR in low Society of Thoracic Surgeons (STS) score risk patients remain to be clarified. This study aimed to explore the feasibility of TAVR treatment in different STS-risk patients and to compare the adverse events between the groups. In this study, patients with PSAR who underwent TAVR at Zhongshan Hospital, Fudan University, China, during the inclusion period were included and categorized into 3 groups based on STS scores. The baseline data, imaging results, and follow-up data of the patients were documented. Therefore, of 75 TAVR patients, 38 (50.7%) were categorized as low risk (STS <4), and 37 (49.3%) patients were categorized as intermediate and high risk (STS ≥4). Compared with patients at intermediate and high risk, those in the low-risk group were younger, had a lower body mass index, had a lower prevalence of hypertension, chronic obstructive pulmonary disease, and previous percutaneous coronary intervention, and had better cardiac function (p all <0.05). In the hospital and at the 1-month follow-up, the degree of aortic regurgitation and cardiac function were significantly improved. No significant difference was found between the 2 groups in the hospital or during the 30-day follow-up. In conclusion, TAVR for PSAR in low-STS-risk patients is safe and efficient during 30 days of follow-up compared with intermediate- and high-STS-risk groups. TAVR for PSAR should not be limited to inoperable or STS-defined high-risk patients. Long-term follow-up is needed for further investigation.

Baroreflex Sensitivity as a Surrogate Biomarker for Concurrently Assessing the Severity of Arterial Stiffness and Cardiovascular Autonomic Neuropathy in Individuals with Type 2 Diabetes.

This study aimed to investigate whether baroreflex sensitivity (BRS) could serve as a reliable metric for assessing cardiovascular autonomic neuropathy (CAN) and concurrently act as a surrogate biomarker for evaluating the severity of arterial stiffness and CAN in individuals diagnosed with type 2 diabetes mellitus (T2DM). Participants underwent brachial-ankle pulse wave velocity (baPWV) as well as autonomic function evaluations encompassing the Sudoscan-based modified composite autonomic scoring scale (CASS), baroreflex sensitivity, and heart rate variability in time domains and frequency domains. Linear regression analysis was performed to evaluate the influence of independent variables on baPWV and modified CASS. Participants with higher baPWV values were older, with longer diabetes duration, lower body weight, body mass index, waist circumference, elevated systolic and diastolic blood pressure, and mean arterial blood pressure. They also exhibited a higher prevalence of retinopathy as the underlying disease and reduced estimated glomerular filtration rate. Multiple linear regression analysis revealed that age and BRS were significantly associated with baPWV while diabetes duration, UACR, and BRS were significantly associated with modified CASS. Our study confirms the significant association of BRS with baPWV and modified CASS in T2DM, highlighting its pivotal role in linking microvascular and macrovascular complications. This supports BRS as a surrogate marker for assessing both the severity of arterial stiffness and cardiovascular autonomic neuropathy in T2DM, enabling the early identification of complications.

The chronic leukocyte and inflammatory cytokine responses of older adults to resistance training in normobaric hypoxia; a randomized controlled trial

Trial designOlder adults experience chronic dysregulation of leukocytes and inflammatory cytokines, both at rest and in response to resistance training. Systemic hypoxia modulates leukocytes and cytokines, therefore this study characterized the effects of normobaric hypoxia on the leukocyte and cytokine responses of older adults to resistance training.Methods20 adults aged 60–70 years performed eight weeks of moderate-intensity resistance training in either normoxia or normobaric hypoxia (14.4% O2), consisting of two lower body and two upper body exercises. Venous blood was drawn before and after the training intervention and flow cytometry was used to quantify resting neutrophils, lymphocytes, monocytes, eosinophils and basophils, in addition to the subsets of lymphocytes (T, B and natural killer (NK) cells). Inflammatory cytokines were also quantified; interleukin 1 beta (IL-1β), IL-4, IL-6, IL-8, IL-10 and tumor necrosis factor alpha (TNF-α). Acute changes in leukocytes and cytokines were also measured in the 24 h following the last training session.ResultsAfter the intervention there was a greater concentration of resting white blood cells (p = 0.03; 20.3% higher) T cells (p = 0.008; 25.4% higher), B cells (p = 0.004; 32.6% higher), NK cells (p = 0.012; 43.9% higher) and eosinophils (p = 0.025; 30.8% higher) in hypoxia compared to normoxia, though the cytokines were unchanged. No acute effect of hypoxia was detected in the 24 h following the last training session for any leukocyte population or inflammatory cytokine (p < 0.05).ConclusionsHypoxic training caused higher concentrations of resting lymphocytes and eosinophils, when compared to normoxic training. Hypoxia may have an additional beneficial effect on the immunological status of older adults.Trial registrationAustralian New Zealand Clinical Trials Registry (ANZCTR). Trial number: ACTRN12623001046695. Registered 27/9/2023. Retrospectively registered. All protocols adhere to the COSORT guidelines.

Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

The objective of the current study was to investigate the association between lower body bone fractures occurring during maintenance hemodialysis and prognosis. This study included 151 hemodialysis patients at the dialysis center of our hospital as of December 2017, and data were systematically gathered from medical records over a period of 5 years, concluding in December 2022. Fourteen patients, 3.0 per 100 person-years, in 151 hemodialysis patients suffered from lower body bone fractures. The ratio of males was significantly lower, and age was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Duration of hemodialysis prior to entry into this study was significantly shorter in the lower body bone fracture group than in the no lower body bone fracture group. Serum albumin was significantly lower and alkaline phosphatase was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Mortality rate was significantly higher in the lower body bone fracture group (85.7%) compared to no lower body bone fracture group (28.5%) (p = 0.01). Kaplan-Meier survival curves for mortality showed that lower body bone fracture group had poor prognosis compared to no lower body bone fracture group. Multivariable-adjusted odds ratio for mortality were significantly higher for cases with lower body bone fractures. Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

Abstract PO2-12-03: Home-based Resistance Exercise Improves Fatigue and Functional Strength in Female Breast Cancer Survivors Post Chemotherapy

Abstract Introduction: Chemotherapy is associated with an increase in fatigue and loss of strength in female breast cancer (BCa) survivors. Strength training has been found to reverse these effects, however, the COVID pandemic added a complexity to clinic-based exercise intervention. The purpose of this study is to determine if a home-based resistance exercise program can attenuate these debilitating effects in a cohort of breast cancer survivors that have recently completed chemotherapy. Methods: Ten BCa survivors who completed chemotherapy within the previous 6 months were recruited to participate in a 12-week home-based resistance exercise proof of concept study. Exercise was performed 3 times per week, supervised via Zoom. Participants completed 2-3 sets of upper body and lower body exercises to volitional fatigue. Self-reported fatigue was measured using the respective subscale from the EORTC QLQ-C30. Strength was measured using hand grip dynamometry and isometric leg strength. Physical function was measured using the 6-minute walk test. Assessments were completed at baseline and end of study. As a comparison, age matched controls (AMCs) were recruited to complete cross-sectional analysis of each of these variables. A one-way analysis variance was done with Tukey’s post hoc test. Significance was set at p&amp;lt; 0.05. Results: BCa survivors were 46.4 ± 12.5 years old with a BMI of 28.11 ± 5.25. AMCs were 50.3 ±13.3 years old with a BMI of 30.8 ± 5.8. There was no significant difference in patient characteristics. A significant difference in self-reported fatigue was found between groups (F=18.52; p&amp;lt; 0.0001). Post hoc analysis found significant difference in fatigue between BCa survivors at baseline (48 ± 23) and the age matched controls (p&amp;lt; 0.0001). Exercise was able to significantly reduce fatigue in BCa survivors (21 ± 15; p=0.003) to levels not significantly different to AMCs (3.3 ± 7.5). A significant difference was also observed between groups for right-hand grip strength (F= 4.923; p=0.015) and left-hand grip strength (F=8.685, p=0.001). Post hoc analysis found a significant increase in right hand grip strength in the BCa survivor group following the intervention (p=0.012). Left hand grip strength was found to be significantly lower at baseline than AMCs (p=0.048). Left hand grip strength was significantly increased in BCa survivors at end of study (p&amp;lt; 0.001). Finally, a significant difference was observed between groups for isometric leg strength (F= 3.699; p=0.038). Post hoc analysis found a significant difference in leg strength in the BCa survivor group following intervention (pre: 105.9 ± 50.6 N-M; post: 158.4 ± 13.2 N-M; p=0.030) which was 16.5% higher than AMCs (127.4 ± 36.5 N-M). No significant difference was found in 6-minute walk distance. However, there was a 21% increase in the distance walked for BCa survivors after interventions (pre: 441.2 ± 66.5m; post: 501.4 ± 123m), identical to distances walked by AMCs (501.4 ± 90.8m). Conclusion: The results of our study suggest that a virtually supervised resistance exercise program can attenuate the negative effects of chemotherapy in BCa survivors to levels similar to their peers that never had breast cancer. Further research using powered sample sizes is needed to validate these results. Citation Format: Taylor Moncrief, Crisann Moon, Angela Gonzalez, Allison Stepanenko, Tiffany Cortes, Darpan Patel. Home-based Resistance Exercise Improves Fatigue and Functional Strength in Female Breast Cancer Survivors Post Chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-12-03.

Heel riser height influence on kinematics and muscle activity of ski mountaineering – A field based study

Introduction The ski binding plays an important role in ski mountaineering. When traveling uphill, the binding has an adjustable heel height known as the riser. Previous laboratory research reported joint kinematics and kinetics are influenced by riser height, however little is known about changes to muscle activity associated with differing joint motion. The purpose of this work was to assess riser height influence on kinematics and muscle activity at different slopes during on-snow skiing. Methods Three female and nine male recreational ski mountaineers (19-26 y) were tested on 5o and 16o gradients using no riser (0 cm) and riser (5.3 cm) at a submaximal 80% HRmax. Each subject used Backland 85 UL skis and Backland Bindings (Atomic Skis, Altenmarkt, Austria). Subjects skied for 6 min at each binding setting with the last 10 gait-cycles evaluating lower limb joint motion gathered from 2D-sagittal plane motion capture. Electromyography (EMG) collected unilaterally on the rectus femoris, biceps femoris, medial gastrocnemius and triceps brachii also. Results 5o slope: hip range of motion (ROM) decreased (p = .003), ankle ROM decreased (p = .005), stride length decreased (p = .004), rating of perceived exertion (RPE) increased (p = .02) for riser compared to no riser. At 16o slope: hip ROM decreased (p = .001), and RPE decreased (p = .004) for riser compared to no riser. HR, glide distance, velocity, EMG, and net mechanical efficiency were not different between riser heights on either slope. Discussion/Conclusion Lower body joint kinematics, step length and RPE varied significantly with riser height. Kinematic differences did not impact velocity or muscle activity when controlling pace. These results agree with previous findings showing minimal differences in EMG and HR while lower body kinematics and RPE changed with riser height.

Investigating the effect of lower body local radiant warming on occupant thermal comfort in battery electric vehicles during cold conditions

The wintertime decrease in the driving range of battery electric vehicles (BEVs), partially attributed to cabin heating with improper setpoints, necessitates the improvement of occupant thermal comfort with reduced energy consumption. While local warming shows promise, understanding its impact on occupant comfort with thermal transients from cabin heating, ventilation, and air conditioning (HVAC) is limited. To address this gap, we investigated thermal perception in twenty-five participants under three distinct warming modes within BEVs operating through typical winter conditions: HVAC alone, HVAC with continuous lower body local radiant warming (LRW), and HVAC with periodic lower body LRW. Results show that the rapid change in skin temperature from lower body local warming does not immediately improve comfort. While a significant improvement in comfort (p < 0.05) is observed with lower body warming, it becomes evident only when the cabin transients subside. Consequently, we propose a framework that advocates for reducing HVAC setpoint and control of LRW of the lower body based on occupant preferences. Our feasibility study demonstrates a 45.3 % reduction in energy consumption by reducing the HVAC setpoint from 25 to 18 °C. These findings enhance the prospects for efficient thermal comfort management in BEVs.

Effects of different strength and velocity training programs on physical performance in youth futsal players

Futsal is a high intensity team sport with intermittent actions of short duration, so it is necessary to include different training strategies to improve explosive actions. There is a gap in the scientific literature regarding training programs that improve the performance of young futsal players. The aim of this study was to determine the effects of different strength and velocity training programs on lower body physical performance in youth futsal players. Forty-two youth futsal players were divided into control group (CG, n = 14) and a strength intervention group (SG, n = 14), which included a weekly session for 8 weeks of eccentric strength training, plyometrics and core strengthening, and a velocity intervention group (VG, n = 14), which included a weekly session during 8 weeks of training with linear speed exercises and with change of direction, accelerations with resistance bands and core strengthening. SG significantly improved horizontal jump (HJ) (p:0.02), V-CUT (p:0.91) and change of direction deficit (CODD) (p:0.01). VG showed significant improvements in HJ (p:0.01), in 25 m sprint (p:0.01), in total repeated sprint ability time (p:0.01), in V-CUT (p:0.01) and in CODD (p:0.01). SG showed significant intergroup differences (p:0.01) in COD variables with respect to CG and VG. In conclusion, SG and VG showed significant improvements in lower body performance variables in youth futsal players. In addition, the SG has substantial changes in COD compared to the other two groups, so it has a greater effect.

INDIVIDUAL STRENGTH CHANGES FOLLOWING A VERY BRIEF INTERVENTION ON NATIONAL STRENGTH TRAINING GUIDELINES IN ADULTS AGED 50 - 75 YEARS

BACKGROUND There is little evidence that the public or healthcare practitioners are aware of and implementing the strength training component of the United Kingdom’s (UK) Chief Medical Officers’ physical activity guidelines in practice. Our study aimed to objectively measure strength following a very brief intervention with the strength component to determine if this practice could increase muscle strength. METHODS This was a mixed method, one-arm, pre-post six-month study. Thirty adults aged 50-75 years had hand grip (upper) isometric strength and ankle plantarflexion (lower) isometric strength measured. The average of two trials on the dominant limb were recorded. Participants were provided a physical copy of the guidelines and were asked to follow the strength recommendations. The very brief intervention (five minutes) included information on why and how to follow the strength guidelines, example exercises, along with a proven behaviour change technique (providing a journal to record training sessions). Strength was tested after six-months. RESULTS The group average indicated that there was no change in upper or lower body strength from baseline. However, when data were viewed individually, upper body strength was gained in 21 of 30 participants and lost in 9 (range: -4.5 to +6 kg). 42% of participants gained more than 2 kg in hand strength after six-months. Lower body strength was gained in 15 participants and lost in 15 (range: -12.4 to +8.65 kg). 43% of participants lost more than 2 kg. Qualitatively participants took the opportunity to ‘procure some new weights’ as they found their weights at home ‘too easy.’ Participants had a new-found realisation that ‘strength training is vital to muscle strength.’ Some mentioned that ‘strength training is now part of my life.’ On the other hand, other participants wanted more, noting that ‘there should be more publicity, information about [strength training] to the general public’ and found it unnecessarily ‘hard to find [follow up information] online.’ CONCLUSIONS In the movement to make ‘every contact count,’ a very brief intervention has been shown to raise awareness and change strength training behaviour. Healthcare practitioners should focus on lower body exercise examples alongside progression techniques to avoid rapid loss in lower body strength. Public health stakeholders need to work together to provide easily accessible strength training resources.