Femoris Muscle Research Articles

Degeneration of the cartilage quality is correlated with a higher intramuscular fat infiltration of the vastus medialis in older adults with pre-to-mild knee osteoarthritis.

To quantitatively verify whether degeneration in the quality of the medial femoral cartilage is correlated with muscle volume loss and intramuscular adipose tissue (IntraMAT) infiltration in quadriceps using magnetic resonance imaging (MRI). Of the 66 older adult participants ≥60years old (74.5±6.9 years), 29 were female. All participants were patients with pre-to-mild knee osteoarthritis. Muscle volume and IntraMAT infiltration of the four individual muscles, the rectus femoris (RF), vastus medialis (VM), vastus intermedius, and vastus lateralis were assessed, using proton density-weighted and 2-point Dixon MR images. Based on the MRI T2 mapping, the T2 relaxation times of the weight-bearing surface of the medial femoral cartilage were calculated. Simple linear regression analyses were performed, evaluating the correlations between the T2 relaxation time of the medial femoral cartilage and quadriceps muscle volume and IntraMAT. Multiple linear regression analysis using a stepwise method was performed, determining which indicators of the four individual muscles correlated with cartilage quality degeneration. Simple linear regression analyses revealed that a longer T2 relaxation time of the medial femoral cartilage was positively correlated with IntraMAT infiltration of the entire quadriceps muscle, RF, and VM, however not with the quadriceps muscle volume. Multiple linear regression analysis revealed that VM IntraMAT was particularly correlated with the extension of T2 relaxation time of the medial femoral cartilage. In older adults with pre-to-mild knee osteoarthritis, IntraMAT infiltration of the quadriceps muscles, particularly of the VM was correlated with degeneration in the quality of the medial femoral cartilage.

The effect of sciatic nerve block on sciatic nerve depth and pain level in patients with ankle fracture based on different approaches under ultrasound guidance.

To investigate the clinical efficacy of using different approach sciatic nerve blocks on the sciatic nerve depth and pain degree in patients with ankle fracture. A retrospective analysis was conducted on 151 patients with ankle fractures who were admitted to the hospital from May 2020 to May 2023. The patients were divided into a control group (n=76) using the greater trochanteric plane approach (GTA) and an observation group (n=75) using the suprapopliteal approach (PA). Perioperative related indexes, pain levels, muscle strength, hemodynamic indexes, and adverse reactions were compared between the two groups. There was no significant difference in operation time between the two groups. The nerve block operation time and onset time were lower in the observation group, while the maintenance time of nerve block was higher in the observation group(P<0.05). The visual analogue scale (VAS) scores at 2h, 12h, and 24h postoperatively were lower in the observation group. Muscle strength of the posterior femoral muscle group was significantly better in the observation group at 8h after surgery. Hemodynamic indexes were lower in the observation group at 15minutes and 30minutes after anesthesia. The total incidence of adverse reactions was lower in the observation group compared to the control group. Ultrasound-guided sciatic nerve block using the suprapopliteal approach in patients with ankle fractures can help stabilize muscle strength and hemodynamics, alleviate pain symptoms, and avoid motor block and adverse reactions. This approach is recommended for adoption.

Features of the microstructure of the quadriceps femoral muscle of broiler chickens of the smena-9 cross with various feeding diets

The article presents the results of studies of the histological and ultrastructural characteristics of the quadriceps femoral muscle of broiler chickens of the Smena-9 cross on the 35th day of postembryonic ontogenesis using feed additives (probiotic, prebiotic, sorbent) of domestic production in addition to the basic feeding diet.The work was implemented within the framework of the thematic task plan for the implementation of research works under the state order of the Ministry of Agriculture of the Russian Federation (Agreement No. 082-03-2023-238 dated 30.01.2023) on the topic: "Development of theoretical foundations and methodology for the practical use of morphological criteria in assessing the quality and safety of poultry products." It has been shown that against the background of the use of feed additives, an increase in the weight of chickens occurs. At the same time, the microstructure of the rectus head of the quadriceps femoris of birds of the control and experimental groups, while maintaining the general plan of structure (the presence of muscular and connective tissue components, bundle organization), is not the same. Based on studies using light and transmission electron microscopy, it was shown that the signs of morphological maturity of skeletal muscle tissue are most pronounced when using a probiotic, in the case of using a prebiotic and a sorbent, muscle fibers grow less synchronously, which is manifested by the variability of their thickness. The thickness of muscle fibers, their bundles, the state of the mitochondrial apparatus, the packing density of myofibrils and their thickness, the degree of development of endomysium and perimysium and the presence of white adipose tissue can be objective morphological and morphometric criteria for assessing the condition of muscle tissue, which correlates with the taste qualities of poultry meat. Data on the structural organization of the quadriceps muscle of the new domestic cross expand the theoretical base in the field of the myology of farm birds, including in terms of identifying morphological signs of the realization of genetic potential against the background of the use of different feeding diets in chicken rearing technology, which allows us to quickly assess the effectiveness of chicken rearing technology and predict an increase in productivity.

HSP70 is upregulated after heat but not freezing stress in the freeze-tolerant cricket Gryllus veletis.

Heat shock proteins (HSPs) are well known to prevent and repair protein damage caused by various abiotic stressors, but their role in low temperature and freezing stress is not well-characterized in insects compared to other thermal challenges such as heat stress. Ice formation in and around cells is hypothesized to cause protein damage, yet many species of insects can survive freezing, suggesting HSPs may be an important mechanism in freeze tolerance. Here, we studied HSP70 in a freeze-tolerant cricket Gryllus veletis to better understand the role of HSPs in this phenomenon. We measured expression of one heat-inducible HSP70 isoform at the mRNA level (using RT-qPCR), as well as the relative abundance of total HSP70 protein (using semi-quantitative Western blotting), in five tissues from crickets exposed to a survivable heat treatment (2h at 40°C), a 6-week fall-like acclimation that induces freeze tolerance, and a survivable freezing treatment (1.5h at -8°C). While HSP70 expression was upregulated by heat at the mRNA or protein level in all tissues studied (fat body, Malphigian tubules, midgut, femur muscle, nervous system ganglia), no tissue exhibited HSP70 upregulation within 2-24h following a survivable freezing stress. During fall-like acclimation to mild low temperatures, we only saw moderate upregulation of HSP70 at the protein level in muscle, and at the RNA level in fat body and nervous tissue. Although HSP70 is important for responding to a wide range of stressors, our work suggests that this chaperone may be less critical in the preparation for, and response to, moderate freezing stress.

Research progress on mechanisms and pharmacokinetics of ligustilide in treatment of locomotor system diseases

Ligustilide, a phthalide compound extracted from Umbelliferae plants such as Angelica sinensis and Ligusticum chuanxiong, has been proven to possess various pharmacological activities, such as anti-inflammatory, anti-tumor, anti-atherosclerosis, anti-ischemic stroke injury, and anti-Alzheimer's disease properties. In recent years, it has shown great potential, particularly in the treatment of locomotor system diseases. Studies have shown that ligustilide has significant therapeutic effects on various locomotor system diseases, including osteoporosis, osteoarthritis, femoral head necrosis, osteosarcoma, and muscle aging and injury. Its mechanisms of action include enhancing the differentiation ability of osteoblasts(OBs), inhibiting the formation ability of osteoclasts(OCs), downregulating inflammatory factors, promoting the synthesis of extracellular matrix(ECM), improving local blood supply to the femoral head, balancing lipid metabolism, inhibiting the proliferation and migration of osteosarcoma cells, inducing cell cycle arrest, enhancing glucose utilization in skeletal muscle, and regulating autophagy and apoptosis. However, its clinical application is severely limited by drawbacks such as structural instability, poor water solubility, and low bioavailability. Currently, formulation techniques such as dripping pills, micropills, inclusion complexes, and liposomes are being used to improve its stability and water solubility, thereby enhancing its therapeutic efficacy. This article summarized the effects, mechanisms of action, and pharmacokinetics of ligustilide monomers and preparations in the treatment of locomotor system diseases in China and abroad in recent years, aiming to provide reference and guidance for further development and application of ligustilide in this field.

Assessing Clinical Variables Associated With Femoral Muscle Decay as Measured by Point-of-Care Ultrasound in Critically Ill Children.

Skeletal muscle wasting is a common occurrence in critical illness, often resulting in intensive care unit (ICU)-acquired weakness. This study aims to identify clinical factors associated with muscle decay in mechanically ventilated critically ill children. Utilizing point-of-care ultrasound, a noninvasive and cost-effective tool, we assess muscle decay through ultrasound of the quadriceps femoris. A prospective observational study was conducted in a single-center quaternary-care pediatric intensive care unit at a children's hospital. A convenience sample of 103 sedated and mechanically ventilated patients were enrolled in this study. Ultrasound measurements of quadriceps femoris muscle thickness were taken, and daily muscle decay rates were calculated. Demographic, clinical, and outcome data were analyzed for correlations with muscle decay. Among the enrolled patients, 67 had repeat measurements. Muscle thickness change aligned with prior studies, with a mean daily change of -1.9% [IQR -0.8, -5.0]. Adequate cumulative caloric intake (>60% of goal) correlated with less muscle decay compared with inadequate intake (-1.8 vs -2.4%, P < .001). Average daily muscle change correlated with both ICU and hospital length of stay (LOS) (r = .328, P = .007 and r = .393, P = .001). No significant correlations emerged between muscle change and mortality, disease severity, fluid balance, early mobilization, steroid exposure, or sedative and paralytic use. This study demonstrates early and frequent muscle decay in critically ill children, as detected by point-of-care ultrasound. Average daily muscle decay was associated with longer ICU and hospital LOS. Adequate cumulative caloric intake is linked to reduced muscle decay. These findings contribute to understanding muscle wasting in critically ill pediatric patients.

A Skeletal Muscle-Mediated Anticontractile Response on Vascular Tone: Unraveling the Lactate-AMPK-NOS1 Pathway in Femoral Arteries.

The regulation of vascular tone by perivascular tissues is a complex interplay of various paracrine factors. Here, we investigate the anti-contractile effect of skeletal muscle surrounding the femoral and carotid arteries and its underlying mechanisms. Using male and female Wistar rats, we demonstrated that serotonin, phenylephrine, and U-46619 induced a concentration-dependent vasoconstrictor response in femoral artery rings. Interestingly, this response was diminished in the presence of surrounding femoral skeletal muscle, irrespective of sex. No anti-contractile effect was observed when the carotid artery was exposed to its surrounding skeletal muscle. The observed effect in the femoral artery persisted even in the absence of endothelium and when the muscle was detached from the artery. Furthermore, the skeletal muscle surrounding the femoral artery was able to promote an anti-contractile effect in three other vascular beds (basilar, mesenteric, and carotid arteries). Using inhibitors of lactate dehydrogenase and the 1/4 monocarboxylate transporter, we confirmed the involvement of lactate, as both inhibitors were able to abolish the anti-contractile effect. However, lactate did not directly promote vasodilation; rather, it exerted its effect by activating 5' AMP-activated protein kinase (AMPK) and neuronal nitric oxide synthase (NOS1) in the skeletal muscle. Accordingly, Nω-propyl l-arginine, a specific inhibitor of NOS1, prevented the anti-contractile effect, as well as lactate-induced phosphorylation of NOS1 at the stimulatory serine site (1417) in primary skeletal muscle cells. Phosphorylation of NOS1 was reduced in the presence of Bay-3827, a selective AMPK inhibitor. In conclusion, femoral artery-associated skeletal muscle is a potent paracrine and endocrine organ that influences vascular tone in both sexes. Mechanistically, the anti-contractile effect involves muscle fiber type and/or its anatomical location but not the type of artery or its related vascular endothelium. Finally, the femoral artery anti-contractile effect is mediated by the lactate-AMPK-phospho-NOS1Ser1417-NO signaling axis.

Targeted Gene Delivery to Muscle Cells In Vitro and In Vivo Using Electrostatically Stabilized DNA—Peptide Complexes

Genetic constructs must be delivered selectively to target tissues and intracellular compartments at the necessary concentrations in order to achieve the maximum therapeutic effect in gene therapy. Development of targeted carriers for non-viral delivery of nucleic acids into cells, including those in muscle, which is one of the most challenging tissues to transfect in vivo, remains a topical issue. We have studied ternary complexes of plasmid DNA and an arginine–histidine-rich peptide-based carrier coated with a glutamate–histidine-rich polymer bearing skeletal muscle targeting peptide (SMTP) for the gene delivery to muscle tissue. The relaxation of the ternary complexes after polyanion treatment was assessed using the ethidium bromide displacement assay. The developed polyplexes were used to transfect C2C12 myoblasts in full-media conditions, followed by analysis of their toxic properties using the Alamar Blue assay and expression analysis of lacZ and GFP reporter genes. After delivering plasmids containing the GFP and lacZ genes into the femoral muscles of mdx mice, which are model of Duchenne muscular dystrophy, GFP fluorescence and β-galactosidase activity were detected. We observed that the modification of ternary polyplexes with 10 mol% of SMTP ligand resulted in a 2.3-fold increase in lacZ gene expression when compared to unmodified control polyplexes in vivo. Thus, we have demonstrated that the developed DNA/carrier complexes and SMTP-modified coating are nontoxic, are stable against polyanion-induced relaxation, and can provide targeted gene delivery to muscle cells and tissues. The results of this study are useful for a range of therapeutic applications, from immunization to amelioration of inherited neuromuscular diseases.

Safety assessment of electrosurgical electrodes by using mini pig tissue

Electrosurgical electrodes are the main dissecting devices widely used for surgeries throughout the world. The present study aimed to evaluate the thermal injury and safety within animals' organs following a minimally invasive electrosurgery technique with electrosurgical electrode AE40-300 (LIPO) and AE20-80 (LIFT). To ensure the effective application of electrosurgery in a clinical environment, it is crucial to minimize heat-induced injury to nearby tissues. In this study, the skin, liver, kidney, and femoral muscle dissected from 9 minipigs were used in tissue thermal spread experiments. Thermal imaging area analysis, maximum temperature, and time to reach basal temperature were evaluated. Thermography results revealed that the surgical temperature was significantly lower in the minimally invasive electrosurgery with AE40-300 (LIPO) and AE20-80 (LIFT) compared to the predicate device. In addition, AE40-300 (LIPO) and AE20-80 (LIFT) created a relatively small thermal injury area and thermal diffusion. Our results indicated that the tested devices named AE40-300 (LIPO) and AE20-80 (LIFT) reduced excessive thermal injury and could be applied to clinical use safely.

Muscle Fibrosis, NF-κB, and TGF-β Are Differentially Altered in Two Models of Paralysis (Botox Versus Neurectomy).

Objective: Volumetric muscle loss results in intramuscular axotomy, denervating muscle distal to the injury and leading to paralysis, denervation, and loss of muscle function. Once the nerve is damaged, paralyzed skeletal muscle will atrophy and accumulate noncontractile connective tissue. The objective of this study was to determine differences in connective tissue, atrophy, and inflammatory signaling between two paralysis models, botulinum toxin (Botox), which blocks acetylcholine transmission while keeping nerves intact, and neurectomy, which eliminates all nerve-to-muscle signaling. Approach: Twenty male Sprague Dawley rats were randomized and received a sciatic-femoral neurectomy (SFN), Botox-induced muscle paralysis of the proximal femur muscles, quadriceps femoris, hamstrings, and calf muscles (BTX), or sham. Muscle force was measured 52 days postsurgery, and samples were collected for histology, protein, and mRNA assays. Results: SFN and BTX decreased twitch and tetanic force, decreased fiber size by twofold, and increased myogenic expression compared with controls. SFN increased the levels of all major extracellular matrix proteins correlating with fibrosis [e.g., laminin, fibronectin, and collagen type(s) I, III, VI]. SFN also increased profibrotic and proinflammatory mRNA compared with BTX and controls. Innovation: SFN and BTX were similar in gross morphology and functional deficiencies. However, SFN exhibited a higher amount of fibrosis in histological sections and immunoblotting. The present study shows evidence that nerve signaling changes NF-κB and TGF-β signaling, warranting future studies to determine the mechanisms involved. Conclusion: These data indicate that nerve signaling may influence fibrogenesis following denervation, but the mechanisms involved may differ as a function of the method of paralysis.

Far-infrared therapy promotes exercise capacity and glucose metabolism in mice by modulating microbiota homeostasis and activating AMPK

The benefits of physical exercise on human health make it desirable to identify new approaches that would mimic or potentiate the effects of exercise to treat metabolic diseases. However, whether far-infrared (FIR) hyperthermia therapy could be used as exercise mimetic to realize wide-ranging metabolic regulation, and its underling mechanisms remain unclear. Here, a specific far-infrared (FIR) rays generated from graphene-based hyperthermia devices might promote exercise capacity and metabolisms. The material characterization showed that the graphene synthesized by chemical vapour deposition (CVD) was different from carbon fiber, with single-layer structure and high electrothermal transform efficiency. The emission spectra generated by graphene-FIR device would maximize matching those adsorbed by tissues. Graphene-FIR enhanced both core and epidermal temperatures, leading to increased blood flow in the femoral muscle and the abdominal region. The combination of microbiomic and metabolomic analysis revealed that graphene-FIR modulates the metabolism of the gut-muscle axis. This modulation was characterized by an increased abundance of short-chain fatty acids (SCFA)-producing bacteria and AMP, while lactic acid levels decreased. Furthermore, the principal routes involved in glucose metabolism, such as glycolysis and gluconeogenesis, were found to be altered. Graphene-FIR managed to stimulate AMPK activity by activating GPR43, thus enhancing muscle glucose uptake. Furthermore, a microbiota disorder model also demonstrated that the graphene-FIR effectively restore the exercise endurance with enhanced p-AMPK and GLUT4. Our results provided convincing evidence that graphene-based FIR therapy promoted exercise capacity and glucose metabolism via AMPK in gut-muscle axis. These novel findings regarding the therapeutic effects of graphene-FIR suggested its potential utility as a mimetic agent in clinical management of metabolic disorders.

Heteronymous feedback from quadriceps onto soleus in stroke survivors.

Recent findings suggest increased excitatory heteronymous feedback from quadriceps onto soleus may contribute to abnormal coactivation of knee and ankle extensors after stroke. However, there is lack of consensus on whether persons post-stroke exhibit altered heteronymous reflexes and, when present, the origin of increased excitation (i.e. increased excitation alone and/or decreased inhibition). This study examined heteronymous excitation and inhibition from quadriceps onto soleus in paretic, nonparetic, and age-matched control limbs to determine whether increased excitation was due to excitatory and/or reduced inhibitory reflex circuits. A secondary purpose was to examine whether heteronymous reflex magnitudes were related to clinical measures of lower limb recovery, walking-speed, and dynamic balance. Heteronymous excitation and inhibition from quadriceps onto soleus were examined in fourteen persons post-stroke and fourteen age-matched unimpaired participants. Heteronymous feedback was elicited by femoral nerve and quadriceps muscle stimulation in separate trials while participants tonically activated soleus at 20% max. Fugl-Myer assessment of lower extremity, 10-meter walk test, and Mini-BESTest were assessed in stroke survivors. Heteronymous excitation and inhibition onsets, durations, and magnitudes were not different between paretic, nonparetic or age-matched unimpaired limbs. Quadriceps stimulation elicited excitation that was half the magnitude of femoral nerve stimulation. Femoral nerve elicited paretic limb heteronymous excitation was positively correlated with walking speed but did not reach significance because only a subset of paretic limbs exhibited excitation (n = 8, Spearman r = 0.69, P = 0.058). Heteronymous feedback from quadriceps onto soleus assessed in a seated posture was not impaired in persons post-stroke. Despite being unable to identify whether reduced inhibition contributes to abnormal excitation reported in prior studies, our results indicate quadriceps stimulation may allow a better estimate of heteronymous inhibition in those that exhibit exaggerated excitation. Heteronymous excitation magnitude in the paretic limb was positively correlated with self-selected walking speed suggesting paretic limb excitation at the higher end of a normal range may facilitate walking ability after stroke. Future studies are needed to identify whether heteronymous feedback from Q onto SOL is altered after stroke in upright postures and during motor tasks as a necessary next step to identify mechanisms underlying motor impairment.

Function of Bi-Articular Femoral Muscles During the Transition from Sitting to Standing Up

As the elderly population increases, independent living for the aged has become essential for extending a healthy life expectancy, and this requires the maintenance of mobility for daily activities, such as standing up and walking. Among these, standing up, a series of movements involved in getting out of a chair or bed, is the starting point of daily activities. Therefore, it is important to clarify the factors that contribute to accomplishing the transition from sitting to standing up. This study attempted to clarify the relationship between motor characteristics and the mechanism of muscle activity involved in the change from sitting to standing up. Specifically, we focused on the activity of the bi-articular muscles involved in the two joints simultaneously rather than joint torque that is the conventional standard for evaluating motion. We probed the mechanistic characteristics of bi-articular muscle activity as well as the main muscles that function during normal standing up motion, namely a natural standing up movement where the trunk is not vertically restricted, using electromyographic analysis, theoretical analysis using a link model based on the muscle arrangement of the lower limb, and experimental analysis using an actual model that reproduces the functions of these muscles to define the muscular activities of the thigh muscles.

Quanto de perda volumétrica e de força do músculo quadríceps femoral éesperada no pós-operatório da reconstrução do ligamento cruzado anterior?

Quanto de perda volumétrica e de força do músculo quadríceps femoral éesperada no pós-operatório da reconstrução do ligamento cruzado anterior?

Myogenesis of Porcine Muscle Satellite Cells by Extracellular Matrix From Fibrotic Adipose Tissue-Derived Mesenchymal Stem Cells

Cultivated meat relies on the production of muscle tissue using cell culture techniques. Myogenesis is a cellular differentiation process in which muscle satellite cells (SC) transform into myoblasts, or myotubes. The extracellular matrix (ECM) plays a pivotal role in meat quality, myogenesis, SC proliferation, and muscle tissue development to replicate meat texture. Because fibrotic differentiation and ECM are involved in the myogenic process, we aimed to induce myogenesis in SC using fibrotic differentiation of adipose tissue-derived mesenchymal stem cells (ADSC). ADSC, fibroblasts (FC), and SC were isolated from the back fat, ear margin tissues, and femur muscle tissues, respectively, of a 1-year-old Berkshire piglet. ADSC were treated with connective tissue growth factor (CTGF; 0, 12.5, 25, or 50 ng/mL) for 72 h to induce fibrotic differentiation. Conditioned media from differentiated ADSC and FC were prepared and labeled CA-CM and F-CM, respectively. SC were exposed to CA-CM or F-CM to assess their effects on myogenesis. The results demonstrated &amp;alpha;-smooth muscle actin and collagen I as the optimal markers for assessing fibrotic differentiation in ADSC. CTGF significantly elevated both mRNA and protein expression of &amp;alpha;-smooth muscle actin and collagen I (P &amp;lt; 0.05), suggesting that CTGF acts as an inducer of fibrotic differentiation in ADSC. Moreover, CTGF elevated the expression of ECM components (laminin, fibronectin, and collagen I) in ADSC (P &amp;lt; 0.05). mRNA expression of myogenesis-related genes (MyoG, MyoD, Myf5, and Myf6) increased in SC exposed to both CA-CM and F-CM (P &amp;lt; 0.05). Our data revealed that fibrotic differentiation of ADSC increased ECM production, and ECM-containing conditioned medium induced myogenesis in SC. These findings indicate that ECM-containing conditioned medium is a good option for enhancing myogenesis in SC, with potential implications for cultivated meat production.

Effect of the Bacillus subtilis BS20 on physiological and immune parameters in mutant mice Muc2–/–

Introduction. Inflammatory bowel disease (IBD) is a common pathology that cannot be completely cured and requires lifelong therapy. One of the promising and sparing therapeutic strategies is the use of probiotics. Unlike Lactobacillus and Bifidobacterium, which represent the basis of most classical probiotics, Bacillus spp. are spore-forming bacteria that contributes to their resistance to the acidic environment of the stomach. It has been shown that the bacteria Bacillus spp. is an effective therapeutic drug for the relief of intestinal diseases with signs of inflammation and bacterial origin. Since the main factors causing IBD are dysbiosis and inflammation, and strains of Bacillus spp. as probiotics can be potential modulators of immunity and influence the intestinal microbiome, it is necessary to search for new strains of probiotic bacteria, including representatives of Bacillus spp., which have an effect on immunity and physiological indicators in experimental models of IBD. The aim of the scientific research — to study the effect of Bacillus subtilis BS20 spores on the physiological and immune parameters of the mutant mouse line Muc2–/–. Research objectives: Investigate survival of Muc2–/– mice, weight, immune parameters (cytokines and immune cells) and amino acid composition of muscles. Materials and methods. Muc2–/– females were fed spores of Bacillus subtilis BS20 in the amount of 109 CFU for 2 months. Analysis of the amino acid composition of the femoral muscle was performed by capillary electrophoresis. The concentration of cytokines in the supernatant was measured using the Magnetic Luminex assay kit. Determination of the number of lymphocytes was performed by flow cytometry. Results. The addition of Bacillus subtilis BS20 to the diet of mice reduced mortality and body weight loss in Muc2–/– females. We found a decrease in interleukin-6 and an increase in interleukin-17 in the descending colon and an increase in B and T helper lymphocytes in the spleen. Conclusion. B. subtilis BS20 improves the general condition of Muc2–/– mutant mice, has an anti-inflammatory and immunostimulating effect, reducing the level of the cytokine interleukin-6 and increasing the percentage of B cells and T helper cells in the spleen.

Tissue dependence of variation in metabolic rates of harvester ants

Metabolic rates vary tremendously among individuals and across species, and the causes of this variation remain controversial and challenging to identify. We utilized an Agilent Seahorse system to measure the metabolic rates of brains, flight muscles, leg muscles, jaw muscles, digestive tract, fat and reproductive organs of harvester ants of different species, sex and caste, and compared these to whole body metabolic rates. Across Pogonomyrmex species varying an order of magnitude in body size, mass-specific brain metabolic rates declined dramatically in larger species, such that the brain accounted for 43% of whole body metabolism in the smallest species and 14% in the largest. In Veromessor pergandei, males have much higher mass-specific metabolic rates than queens or workers, with queens being slightly higher than workers. The tissue specific bases to metabolic rates varied with sex and caste. Males are "flying gonads", with flight muscle, fat and gonads accounting for 44, 25 and 20%, respectively, of resting metabolic rate, and tissue-specific rates were generally higher in males than females. For queens, which have by far the largest fat content, the fat body contributes the largest fraction of the total tissue metabolic rate (38%), with flight muscle, femoral muscle, brain and gut each contributing 13 – 15% of total cost. For workers, brains are the most important contributors to total tissue metabolic rate (38%), followed by fat body (24%) and gut (19%). Together these results demonstrate that variation in whole body metabolic rate within and across closely related species is strongly affected by size, sex and caste-specific differences in tissue function, likely associated with life history variation. Supported by NSF IOS-1953419. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Tibiofemoral bone configuration is not associated with hamstring muscle strength in male and female patients with ACL reconstruction.

Previous evidence indicated that the tibiofemoral bone configuration might elevate the risk of an anterior cruciate ligament (ACL) injury. Furthermore, a low hamstring-to-quadriceps muscle ratio predisposes especially females to unfavourable knee kinematics. The primary objective of the present study was to investigate sex-specific associations between tibiofemoral bone geometry and isokinetic knee flexion torque in patients with primary ACL injury followed by ACL reconstruction. N = 100 patients (72 = male, 28 = female, age = 31.3 ± 10.2, body mass index = 25.3 ± 3.6) with primary ACL rupture with isokinetic knee flexion torque assessments before and 6 months after ACL reconstruction surgery were analysed. Magnetic resonance imaging scans were analysed for medial posterior tibial slope (MPTS) and lateral posterior tibial slope, notch width index (NWI) and lateral femoral condyle index (LFCI). Additionally, isokinetic knee flexion torque (60°/s) and hamstring-quadriceps ratios were evaluated. Subsequently, functional parameters were correlated with imaging data for gender subgroups. The findings showed that presurgical isokinetic knee flexion torque was not associated with any marker of femoral or tibial bone geometry. Further, while significant differences were observed between female (0.883 ± 0.31 Nm/kg) and male (1.18 ± 0.35 Nm/kg) patients regarding preoperative normalized knee flexion torque (p < 0.001), no significant sex differences were found for percentage increases in normalized knee flexion torque from presurgery to postsurgery. Generally, female patients demonstrated significantly higher MPTS magnitudes (p < 0.05) and lower LFCI values (p < 0.05) compared to men. The present results demonstrated no association between tibial or femoral bone geometry and muscle strength of the hamstrings in patients with ACL reconstruction, indicating an important mismatch of muscular compensation to deviations in bone geometry. There were no sex-specific differences in tibiofemoral bone parameters. Level III.

Nutritional Value and Physicochemical Properties of Male and Female Broad-Breasted Bronze Turkey Muscle.

Colored varieties of turkeys, such as the broad-breasted Bronze, not currently subject to intensive breeding work, are kept only in amateur breeding and treated rather as ornamental poultry. They are raised in extensive systems, which undoubtedly affects the quality of the meat obtained. Consumers are looking for meat with specific and unique sensory qualities; hence, the interest in meat from turkeys with a slower-than-typical growth rate, such as the broad-breasted Bronze, is justified. The object of this research was to analyze the physicochemical properties and nutritional value (amino acid, fatty acid, and antioxidant profile) of the breast and thigh muscles of broad-breasted Bronze turkeys with regard to gender. It was shown that gender had little effect on muscle chemical composition, amino acid, and fatty acid content (p > 0.05), as well as most oxido-reduction indices. However, significant differences were noted in muscle quality traits such as color brightness (L*; turkeys > indors; p = 0.023), proportion of red (a*; turkeys < indors; p = 0.048) and yellow (b*; turkeys > indors; p = 0.039), and water absorption (turkeys < indors; p = 0.009). The type of muscle also had a significant effect on quality characteristics. Higher a*, b*, C*, pH, water absorption, and thermal leakage were shown in the femoral muscle (p < 0.001), while L* and h were higher in the pectoral muscle (p < 0.001). Turkey meat was characterized by a high proportion of unsaturated fatty acids (MUFA + PUFA ~68%), favorable FA index values, and low lipid oxidation indices. Thigh muscles (especially turkey) were more caloric, and contained significantly (p < 0.001) more fat and all major FA groups. Breast muscles (especially of turkeys) were characterized by a high protein content (about 25%) and a high proportion of essential amino acids. The data obtained indicate that broad-breasted Bronze turkeys can provide high-quality meat, and are an excellent option for meeting modern consumer needs.

Molecular evidence of Toxoplasma gondii from the tissue and blood of naturally infected sheep.

Toxoplasmosis is a cosmopolitan zoonotic infection that has significant effects on public health and causes economic losses in the livestock industry. The current study was designed to detect the Toxoplasma parasite in sheep blood samples and tissue samples of slaughtered sheep at the Sulaimani abattoir using molecular technique. A total of 300 peripheral sheep blood samples were randomly collected from 20 small ruminant flocks at 4 locations in the Sulaymaniyah province, northern Iraq. Also, 150 meat samples from thigh muscle, heart, and diaphragm were collected from slaughtered sheep. All collected blood samples were subjected to polymerase chain reaction (PCR) amplification to confirm Toxoplasma infection; in addition, meat samples were also analyzed for Toxoplasma by PCR following the digestion process. Of the 300 amplified blood samples, 94 were considered positive for Toxoplasma gondii, with a prevalence rate of 31.3%. The overall prevalence of Toxoplasma among meat samples was 34%. The diaphragm reported a higher infection rate (46%) than the heart (32%), while the femoral muscle reported an infection rate of 24%. Aged animals (older than 24 months) presented a higher infection rate (32.8%) than younger animals (28.9%). Contact with or consumption of uncooked meat from infected sheep increases the chance of parasite transmission to humans.