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Simple Summary: Although the side bridge test has been widely used for assessing trunk lateral flexor endurance in sport, clinical, and scientific settings, to the best of the authors' knowledge, no study has analyzed its validity and reliability in an only female population. The surface electromyography of eight abdominal, back, shoulder and hip muscles was measured during the test to analyze its validity. A one-week test-retest design was performed to evaluate its reliability. No significant differences were found between the trunk lateral flexors and the deltoids. The study data showed that the test performance could be significantly predicted by external oblique and deltoid normalized median frequency slopes and by body mass and trunk height. Based on the results of this study, the shoulder muscle activation and fatigue and the individuals' anthropometric characteristics, especially the mass, played an important role in the side bridge test performance, which questions the validity of this multi-joint test to specifically assess trunk lateral flexor endurance. In addition, although the side bridge test showed a good data consistency, its intra-subject variability was high, which reduces its utility when small intra-subject changes in muscle endurance are important (e.g., elite sport). The side bridge test (SBT) is one of the most popular tests to assess isometric trunk lateral flexor endurance. The aim of this study was to assess the validity and reliability of the SBT in healthy females. Twenty-four (24.58 ± 3.92 years) physically active (1–2 h of moderate physical activity, 2–3 times a week) females voluntarily participated in this study. The surface electromyography (EMG) of eight abdominal, back, shoulder and hip muscles was measured during the SBT. Normalized median frequency slopes (NMFslope) were calculated to analyze the muscle fatigue. The EMG amplitudes were normalized to maximum EMG values to assess muscle activity intensity. A one-week test-retest design was performed to evaluate the SBT reliability through the ICC3,1 and typical error. Higher NMFslopes and normalized EMG amplitudes were found in deltoids, abdominal obliques, rectus abdominis, and erector spinae in comparison to latissimus dorsi, gluteus medius, and rectus femoris. However, no significant differences were found between the trunk lateral flexors and the deltoids. Linear regression analysis showed that SBT performance could be significantly predicted by external oblique and deltoid NMFslope (adjusted R2 = 0.673) and by body mass and trunk height (adjusted R2 = 0.223). Consistency analysis showed a high intraclass correlation coefficient (0.81) and a relatively high typical error (10.95 s). Despite the good relative reliability of the SBT, its absolute reliability was low and its validity questionable, as the shoulder muscle activation and fatigue and the individuals' anthropometric characteristics played an important role in SBT performance. [ABSTRACT FROM AUTHOR]

Neutrophils are the first line of defence against invading pathogens. Although neutrophils are well-known professional killers, some pathogens including Leishmania (L.) parasites survive in neutrophils, using these cells to establish infection. Manipulation of neutrophil recruitment to the infection site is therefore of interest in this cutaneous disease. The c-MET tyrosine kinase receptor was shown to promote neutrophil migration to inflamed sites. Here, we investigated the importance of c-MET expression on neutrophils in their recruitment to the infection site and the role of c-Met expression in the pathology of leishmaniasis. Following infection with L. mexicana, mice with conditional deletion of c-MET in neutrophils controlled significantly better their lesion development and parasite burden compared to similarly infected wild type mice. Our data reveal a specific role for c-MET activation in Leishmania-induced neutrophil infiltration, a process correlating with their negative role in the pathology of the diseases. We further show that c-MET phosphorylation is observed in established cutaneous lesions. Exposure to L. mexicana upregulated c-Met expression predominantly in infected neutrophils and c-Met expression influenced ROS release by neutrophils. In addition, pharmacological inhibition of c-MET, administrated once the lesion is established, induced a significant decrease in lesion size associated with diminished infiltration of neutrophils. Both genetic ablation of c-MET in neutrophils and systemic inhibition of c-MET locally resulted in higher levels of CD4+T cells producing IFNγ, suggesting a crosstalk between neutrophils and these cells. Collectively, our data show that c-MET activation in neutrophils contributes to their recruitment following infection, and that L. mexicana induction of c-MET on neutrophils impacts the local pathology associated with this disease. Our results suggest a potential use for this inhibitor in the control of the cutaneous lesion during this parasitic infection. Author summary: The leishmaniases are a complex of diseases caused by Leishmania protozoan parasites. There exist different forms of the disease, ranging from cutaneous lesions to visceral disease, the latter being fatal if not treated. Cutaneous leishmaniasis is the most common form with one million new cases occurring annually. Increasing evidence points to an important role for neutrophils in disease outcome and these cells were shown to play a deleterious role following infection with several Leishmania spp., including L. mexicana. Here, we investigated the role of the c-MET receptor tyrosine kinase in the outcome of cutaneous leishmaniasis. c-MET has been shown to be involved in neutrophil recruitment to inflamed sites. We show here that L. mexicana induce c-MET expression and phosphorylation predominantly in neutrophils. Using mice genetically deficient for c-MET in neutrophils, a better control of lesion size and parasite load was observed. Furthermore, injection of a specific inhibitor of c-MET, once the lesion is established, significantly decreased the cutaneous pathology. The results presented here reveal that c-MET is contributing to the pathology induced by L. mexicana and suggest that the use of c-MET inhibitors could ameliorate the cutaneous lesion pathology. [ABSTRACT FROM AUTHOR]

Mutations in APC promote colorectal cancer (CRC) progression through uncontrolled WNT signaling. Patients with desmoplastic CRC have a significantly worse prognosis and do not benefit from chemotherapy, but the mechanisms underlying the differential responses of APC-mutant CRCs to chemotherapy are not well understood. We report that expression of the transcription factor prospero homeobox 1 (PROX1) was reduced in desmoplastic APC-mutant human CRCs. In genetic Apc-mutant mouse models, loss of Prox1 promoted the growth of desmoplastic, angiogenic, and immunologically silent tumors through derepression of Mmp14. Although chemotherapy inhibited Prox1-proficient tumors, it promoted further stromal activation, angiogenesis, and invasion in Prox1-deficient tumors. Blockade of vascular endothelial growth factor A (VEGFA) and angiopoietin-2 (ANGPT2) combined with CD40 agonistic antibodies promoted antiangiogenic and immunostimulatory reprogramming of Prox1-deficient tumors, destroyed tumor fibrosis, and unleashed T cell-mediated killing of cancer cells. These results pinpoint the mechanistic basis of chemotherapy-induced hyperprogression and illustrate a therapeutic strategy for chemoresistant and desmoplastic CRCs. [ABSTRACT FROM AUTHOR]

Objectives: Determine if (a) a better trunk stability and endurance are associated with an improved whole‐body dynamic balance, and if (b) the assessment tests can be interchanged within each capability. Methods: Sixty‐three physically active young males performed three trunk stability (i.e., the lumbopelvic stability, the unstable sitting and the sudden loading sitting tests), three trunk muscle endurance (i.e., the Biering–Sørensen, the side bridge and the front bridge tests) and four whole‐body dynamic balance (i.e., the tandem and the single‐leg stance, the Y‐Balance, and the single‐leg triple hop tests) tests two times. After assessing the reliability of the variables, a Pearson correlation analysis was performed. Results: The correlations between trunk stability and endurance tests with dynamic balance tests were non‐significant except for the unstable sitting test with both the tandem (r = 0.502) and the single‐leg stance (r = 0.522) tests. Moreover, no relationships were observed between the trunk stability and the trunk muscle endurance tests. Interestingly, no relationships were found between most tests within each capability (i.e., trunk stability, trunk endurance, and dynamic balance) except: (i) the front bridge stability test and the back (r = 0.461) and the side (r = 0.499) bridge stability tests; (ii) the two side bridge endurance tests (r = 0.786); (iii) the tandem and the single‐leg stance tests (0.439 ≤ r ≤ 0.463); (iv) the Y‐Balance and the single‐leg triple hop tests (0.446 ≤ r ≤ 0.477). Conclusion: Better trunk function does not seem to be a relevant factor for dynamic balance in young active males. In this population, specific measures are needed as the test interchangeability is questioned. [ABSTRACT FROM AUTHOR]

Heredia-Elvar, JR, Juan-Recio, C, Prat-Luri, A, Barbado, D, R'ıos-Calonge, Jdl, and Vera-Garcia, FJ. Exercise intensity progressions and criteria to prescribe core stability exercises in young physically active men: a smartphone accelerometer-based study. J Strength Cond Res 38(2): 266-273, 2024--The establishment of core stability (CS) exercise intensity progressions in sport and clinical settings is normally based on subjective criteria. Therefore, this study aimed to develop exercise intensity progressions for some of the most common CS exercises through smartphone accelerometry and to analyze the effect of the subjects' lumbopelvic postural control on these progressions. Fifty-seven healthy young physically active male students performed 7 isometric variations of front bridge, back bridge, side bridge, and bird-dog exercises with a smartphone accelerometer placed on the pelvis. Mean pelvic accelerations were calculated during each variation to evaluate the lumbopelvic postural control challenge imposed on the subjects as an index of exercise intensity of difficulty. For the bridge exercises, long bridging produced higher pelvic accelerations than short bridging, bridging with single-leg support was more intense than bridging with double-leg support (even with both legs on a hemisphere ball for the back and front bridge), and the most difficult variations were those performed on a Swiss ball, mainly the variations with single-leg support. For the bird-dog exercise, the 2-point positions weremore intense than the 3-point positions, the variations performed with a knee on the hemisphere ball produced higher pelvic accelerations than similar variations performed with the forearm on the hemisphere ball, and the variationswith limbmotions generated higher pelvic accelerations than similar variations performed without limbmotions. Although the CS exercise progressionswere very similar across subjects, our results showed the need to individualize the prescription of theCS exercise progressions based on the subjects' lumbopelvic postural control level. [ABSTRACT FROM AUTHOR]

Intracellular pathogens that replicate in host myeloid cells have devised ways to inhibit the cell's killing machinery. Pyroptosis is one of the host strategies used to reduce the pathogen replicating niche and thereby control its expansion. The intracellular Leishmania parasites can survive and use neutrophils as a silent entry niche, favoring subsequent parasite dissemination into the host. Here, we show that Leishmania mexicana induces NLRP1- and caspase-1-dependent Gasdermin D (GSDMD)-mediated pyroptosis in neutrophils, a process critical to control the parasite-induced pathology. In the absence of GSDMD, we observe an increased number of infected dermal neutrophils two days post-infection. Using adoptive neutrophil transfer in neutropenic mice, we show that pyroptosis contributes to the regulation of the neutrophil niche early after infection. The critical role of neutrophil pyroptosis and its positive influence on the regulation of the disease outcome was further demonstrated following infection of mice with neutrophil-specific deletion of GSDMD. Thus, our study establishes neutrophil pyroptosis as a critical regulator of leishmaniasis pathology. Author summary: Leishmaniases are neglected infectious diseases with around 1 million new cases reported per year. Neutrophils are rapidly and massively recruited to the site of infection. Several Leishmania species including Leishmania mexicana, inhibit the host neutrophil antimicrobial response, using these cells as an entry shelter. Here, we discover a novel host defense mechanism against Leishmania mexicana that controls neutrophil presence at the onset of infection. The inflammasomes are multiprotein signaling complexes that detect infection and induce pyroptotic cell death. We show that the NLRP1 inflammasome is important in the control of lesion development and parasite burden. We identify NLRP1-driven GSDMD pyroptosis in neutrophils as critical in the control of the early neutrophil pool, impacting the outcome of infection. Taken together, we show that neutrophil pyroptosis is an essential player in cutaneous leishmaniasis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Body tilt changes could affect the intensity/difficulty of core stability exercises, but there is still a lack of knowledge about its impact. OBJECTIVE: To analyse the trunk muscles activation during prone plank exercises at different body tilts. METHODS: Twenty-four young adults who performed recreational gymnastic activities participated in this study. Electromyography activity of the rectus abdominis (RA), external oblique (EO), internal oblique (IO) and erector spinae (ES) was recorded during the performance of six variations of the prone plank exercise (planking with feet supported on the ground [conventional horizontal position] and planking with feet supported on wall bars at five different heights increasing the angle tilt) and an inverted position exercise. RESULTS: The RA, EO and IO activation in all prone plank variations were higher than those observed in the conventional prone plank. In addition, the coefficient of variation of the muscle activation increased with the declination angle, reaching the highest values in the inverted position for the RA and ES muscles. CONCLUSION: The results seem to indicate that the body tilt variation could be used as an easy and inexpensive strategy for modulating the neuromuscular demands and the motor control challenge during planking exercises. [ABSTRACT FROM AUTHOR]

Purpose: The intensity progression of core stabilization exercises (CSEs) is usually based on personal criteria rather than on objective parameters. To develop exercise progressions for four of the most common CSEs based on the postural control challenge imposed on the participants, and to analyze the effect of participants' sex and postural control level on these progressions.Methods: Seventy-six males and females performed five variations of front bridge, back bridge, side bridge and bird-dog exercises on two force platforms. The mean velocity of the center of pressure displacement was calculated to assess exercise intensity through the measurement of the participants' body sway (PBS).Results: In general, long bridges produced higher PBS than short bridges, bridging with single leg support produced higher PBS than bridging with double leg support and bridging on a hemisphere ball produced higher PBS than bridging on the floor. The most difficult bridging variations were those performed on a hemisphere ball with single leg support. Regarding the bird-dog, two-point positions produced higher PBS than three-point positions and the positions performed on a hemisphere ball produced higher PBS than those performed on the floor.Conclusion: The CSE progressions obtained by males and females were very similar. However, the participants with high trunk control showed less significant differences between exercise variations than the participants with low trunk control, which shows the need to individualize the progressions according to the participants' training level. Overall, this study provides useful information to guide the prescription of CSE progressions in young physically active individuals. [ABSTRACT FROM AUTHOR]

Although core stability (CS) training is largely used to enhance motor performance and prevent musculoskeletal injuries, the lack of methods to quantify CS training intensity hinders the design of CS programs and the comparison and generalization of their effects. The aim of this study was to analyze the reliability of accelerometers integrated into smartphones to quantify the intensity of several CS isometric exercises. Additionally, this study analyzed to what extent the pelvic acceleration data represent the local stability of the core structures or the whole-body postural control. Twenty-three male and female physically-active individuals performed two testing-sessions spaced one week apart, each consisting of two 6-second trials of five variations of frontal bridge, back bridge, lateral bridge and bird-dog exercises. In order to assess load intensity based on the postural control challenge of CS exercises, a smartphone accelerometer and two force platforms were used to measure the mean pelvic linear acceleration and the mean velocity of the centre of pressure displacement, respectively. Reliability was assessed through the intra-class correlation coefficient (ICC3,1) and the standard error of measurement (SEM). In addition, Pearson coefficient was used to analyze the correlation between parameters. The reliability analysis showed that most CS exercise variations obtained moderate-to-high reliability scores for pelvic acceleration (0.71

To analyze how balance and other physical capacities evolved after surgery in patients with a bimalleolar fracture and how these capacities and clinical variables (immobilization or unloading time) contribute to restoring patients' functionality, 22 patients and 10 healthy people (HC) were assessed for static and dynamic balance (Y-Balance test, YBT), dorsiflexion ankle mobility (ADFROM) and hip strength at 6 and 12 months after surgery. Patients' functional status was assessed through the Olerud Molander Ankle Score (OMAS) and the American Orthopaedic Foot and Ankle Society (AOFAS) score. Twenty-one patients with ankle fractures who completed the study showed a worse static and dynamic balance at 6 months. The YBT in the anterior direction (YBTA) revealed balance deficits in the operated limb at 12 months compared to the non-operated limb (−5.6%) and the HC (−6.7%). They also showed a decreased ADFROM compared to the non-operated limb (−7.4°) and the HC (−11°). In addition, medium-term (6 months) deficits in abductor strength hip but no hip strength deficits were found at 12 months after surgery. Relative weight analyses showed that ADFROM and hip strength explained 35–63% of the YBTA variance and AOFAS/OMAS scores. Balance, hip strength and ADFROM seem to be reliable indexes for assessing the functional status of these patients. These results could help to understand the relationship between these physical capacities and the patients' perceived functional status. [ABSTRACT FROM AUTHOR]

This study measured the peak force (PF) in cadet inline speed skaters (ISS) and verified the physical measures that determine athletes' performance on the Isometric Mid- Thigh Pull Test (IMTP) through a multivariate regression and discriminant canonical analysis. A total of 36 high-performance male (n= 18; age= 17.4± 1.21 years; body mass= 65.1± 6.18 kg; height= 168.6± 5.1 cm) and female (n= 18; age= 17.4± 1.23 years; body mass= 55.5± 4.4 kg; height= 158.6± 5.2 cm) athletes were measured two times (with a 3-day interval). All participants performed the IMTP and sit-and-reach (SR) tests, and an evaluator performed anthropometric circumference measurements on their thighs and calves. The main results indicated that males showed a higher PF on the test (m= 59.0± 3.9 N/kg vs. f= 50.4± 5.8 N/kg; p≤ 0.001) and retest (m= 59.1± 4.2 N/kg vs. f= 51.9± 6.6 N/kg; p≤ 0.001). In the first, thigh circumference (X2= 29.01, p≤ 0.001, R2= 0.74) had an overall 91.7% prediction. The second model included using the SR and thigh circumference (X2= 49.91, p≤ 0.001, R2= 1.0) showed an overall prediction of 100.0%. The thigh circumference matrix showed better predictive power for (coefficient= 7.158) male and female IMTP performance. In conclusion, despite the gender differences, the thigh circumference is a good predictor for PF in cadet ISS athletes. [ABSTRACT FROM AUTHOR]