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JAMA Neurology Jul 2024
PubMed: 38949818
DOI: 10.1001/jamaneurol.2024.2008 -
Life (Basel, Switzerland) May 2024Muscle mass depletion is associated with unfavorable outcomes in many diseases. However, its relationship with cardiac arrest outcomes has not been explored. This...
Muscle mass depletion is associated with unfavorable outcomes in many diseases. However, its relationship with cardiac arrest outcomes has not been explored. This retrospective single-center study determined the relationship between muscle mass depletion and the neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) by measuring muscle mass at various locations. Adult patients with OHCA, who were treated with target temperature management, and who underwent abdominal or chest computed tomography (CT) within 3 months of the cardiac arrest were included. Skeletal muscle index (SMI) was measured at the third lumbar vertebra (L3) level, psoas muscle, fourth thoracic vertebra (T4) level, and pectoralis muscle. The Youden index was used to determine a low SMI based on sex-specific cutoff values. The outcome variables were "good neurological outcome" and "survival" at hospital discharge. Multivariable analyses revealed that patients with low T4 SMI level were significantly associated with good neurological outcomes at hospital discharge (odds ratio = 0.26, 95% confidence interval: 0.07-0.88, = 0.036). However, no significant differences were observed between good neurological outcomes and low SMI at the L3 level and psoas and pectoralis muscles; SMIs were not associated with survival at hospital discharge. T4 level SMI depletion was inversely associated with good neurological outcomes in patients with OHCA. Thoracic muscle depletion may be crucial for predicting the neurological outcomes in patients with OHCA and further investigation in larger prospective study is warranted.
PubMed: 38929664
DOI: 10.3390/life14060680 -
Poultry Science May 2024Wooden Breast (WB) abnormality represents one of the major challenges that the poultry industry has faced in the last 10 years. Despite the enormous progress in...
Wooden Breast (WB) abnormality represents one of the major challenges that the poultry industry has faced in the last 10 years. Despite the enormous progress in understanding the mechanisms underlying WB, the precise initial causes remain to be clarified. In this scenario, the present research is intended to characterize the gene expression profiles of broiler Pectoralis major muscles affected by WB, comparing them to the unaffected counterpart, to provide new insights into the biological mechanisms underlying this defect and potentially identifying novel genes likely involved in its occurrence. To this purpose, data obtained in a previous study through the RNA-sequencing technology have been used to identify differentially expressed genes (DEGs) between 6 affected and 5 unaffected broilers' breast muscles, by using the newest reference genome assembly for Gallus gallus (GRCg7b). Also, to deeply investigate molecular and biological pathways involved in the WB progression, pathways analyses have been performed. The results achieved through the differential gene expression analysis mainly evidenced the downregulation of glycogen metabolic processes, gluconeogenesis, and tricarboxylic acid cycle in WB muscles, thus corroborating the evidence of a dysregulated energy metabolism characterizing breasts affected by this abnormality. Also, genes related to hypertrophic muscle growth have been identified as differentially expressed (e.g., WFIKKN1). Together with that, a downregulation of genes involved in mitochondrial biogenesis and functionality has been detected. Among them, PPARGC1A and PPARGC1B chicken genes are particularly noteworthy. These genes not only have essential roles in regulating mitochondrial biogenesis but also play pivotal roles in maintaining glucose and energy homeostasis. In view of that, their downregulation in WB-affected muscle may be considered as potentially related to both the mitochondrial dysfunction and altered glucose metabolism in WB muscles, and their key involvement in the molecular alterations characterizing this muscular abnormality might be hypothesized.
PubMed: 38908127
DOI: 10.1016/j.psj.2024.103902 -
Nature Jun 2024The subpectoral diverticulum (SPD) is an extension of the respiratory system in birds that is located between the primary muscles responsible for flapping the wing. Here...
The subpectoral diverticulum (SPD) is an extension of the respiratory system in birds that is located between the primary muscles responsible for flapping the wing. Here we survey the pulmonary apparatus in 68 avian species, and show that the SPD was present in virtually all of the soaring taxa investigated but absent in non-soarers. We find that this structure evolved independently with soaring flight at least seven times, which indicates that the diverticulum might have a functional and adaptive relationship with this flight style. Using the soaring hawks Buteo jamaicensis and Buteo swainsoni as models, we show that the SPD is not integral for ventilation, that an inflated SPD can increase the moment arm of cranial parts of the pectoralis, and that pectoralis muscle fascicles are significantly shorter in soaring hawks than in non-soaring birds. This coupling of an SPD-mediated increase in pectoralis leverage with force-specialized muscle architecture produces a pneumatic system that is adapted for the isometric contractile conditions expected in soaring flight. The discovery of a mechanical role for the respiratory system in avian locomotion underscores the functional complexity and heterogeneity of this organ system, and suggests that pulmonary diverticula are likely to have other undiscovered secondary functions. These data provide a mechanistic explanation for the repeated appearance of the SPD in soaring lineages and show that the respiratory system can be co-opted to provide biomechanical solutions to the challenges of flight and thereby influence the evolution of avian volancy.
Topics: Animals; Flight, Animal; Pectoralis Muscles; Wings, Animal; Lung; Birds; Hawks; Respiratory System; Biomechanical Phenomena; Biological Evolution; Models, Biological
PubMed: 38867039
DOI: 10.1038/s41586-024-07485-y -
Surgical and Radiologic Anatomy : SRA Jun 2024In the existing literature, various insertion variations and classifications for the Pectoralis Minor (PMi) muscle have been reported. However, there is limited...
PURPOSE
In the existing literature, various insertion variations and classifications for the Pectoralis Minor (PMi) muscle have been reported. However, there is limited information on inferior origin variations of the PMi muscles and a certain classification is lacking.
CASE PRESENTATION
During routine cadaver dissection of an adult male, variations in the origin of the bilateral PMi muscles were identified. Morphometric measurements of the PMi were conducted using ImageJ software, and the unusual origin patterns of the PMi were categorized into specific types. The PMi muscle demonstrated a bilateral variations. On the right side, the PMi displays a bifid structure comprising medial and lateral fibers. The left PMi originate from the superolateral margins of the 4th to 6th costae and terminate at the anterosuperior surface of the coracoid process. The length of the right medial fiber before merging was 5.67 ± 0.04 cm, while that of the right lateral fiber was 6.68 ± 0.05 cm. The distance between the two fibers was measured as 0.43 cm, with a length of 3.33 ± 0.02 cm. The length and diameter of the muscle fibers extending to the 6th costa were 2.63 ± 0.01 cm and 0.46 cm, respectively.
CONCLUSIONS
Potential variations in PMi arising from impairment during development may occasionally manifest as asymptomatic conditions or predispose individuals to shoulder impingement, rotator cuff dysfunction, shoulder-related disorders, and functional impairments. Therefore, careful attention to this variation is considered in surgical planning.
PubMed: 38858313
DOI: 10.1007/s00276-024-03407-9 -
Annals of Plastic Surgery Jun 2024Ultrasound-guided regional field blocks are not widely used in outpatient plastic surgeries. The efficacy of truncal blocks (PEC1 + SAP) has not been established in... (Comparative Study)
Comparative Study
Local Infiltration Anesthesia Versus Ultrasound-Guided Pectoralis (PEC1) + Serratus Anterior Plane (SAP) Blocks on Postanesthetic Care Unit Pain Control in Patients Undergoing Primary Submuscular Augmentation Mammoplasty.
BACKGROUND
Ultrasound-guided regional field blocks are not widely used in outpatient plastic surgeries. The efficacy of truncal blocks (PEC1 + SAP) has not been established in plastic surgery. The purpose of this study was to analyze the outcomes of these newer anesthetic techniques compared with traditional blind local anesthetic infiltration in patients undergoing breast augmentation.
METHODS
This retrospective institutional review board-approved cohort study compared the outcomes of the different practices of 2 plastic surgeons at the same accredited outpatient surgery center between 2018 and 2022. Group 1 received an intraoperative blind local infiltration anesthetic. Group 2 underwent surgeon-led, intraoperative, ultrasound-guided PEC1 (Pectoralis 1) + SAP (serratus anterior plane) blocks. Patients who underwent any procedure other than primary submuscular augmentation mammoplasty were excluded from the study. The outcomes measured included operative time, opioid utilization in morphine milligram equivalents (MME), pain level at discharge, and time spent in the post anesthetic care unit (PACU).
RESULTS
Sixty patients met the inclusion criteria for each group for a total of 120 patients. The study groups were similar to each other. Patients receiving PEC1 + SAP blocks (group 2) had significantly lower average MME requirements in the PACU (3.04 MME vs 4.52 MME, P = 0.041) and required a shorter average PACU stay (70.13 minutes vs 80.38 minutes, P = 0.008). There were no significant differences in the pain level at discharge, operative time, or implant size between the 2 groups.
CONCLUSIONS
Surgeon-led, intraoperative, ultrasound-guided PEC1 + SAP blocks significantly decreased opioid utilization in the PACU by 33% and patient time in the PACU by 13%, while achieving similar patient pain scores and operating times.
Topics: Humans; Female; Retrospective Studies; Ultrasonography, Interventional; Adult; Nerve Block; Pain, Postoperative; Anesthesia, Local; Mammaplasty; Pain Management; Pectoralis Muscles; Middle Aged; Pain Measurement; Anesthesia Recovery Period; Anesthetics, Local; Cohort Studies
PubMed: 38857002
DOI: 10.1097/SAP.0000000000003948 -
Breast Cancer Research and Treatment Jun 2024An increasing number of women are choosing mastectomy and subpectoral implant (SI) breast reconstruction over breast-conserving therapy (BCT). It is unclear to what...
BACKGROUND
An increasing number of women are choosing mastectomy and subpectoral implant (SI) breast reconstruction over breast-conserving therapy (BCT). It is unclear to what extent these procedures differ in their effect on the pectoralis major (PM). The purpose of this study was to assess the impact of choosing BCT or SI breast reconstruction on PM function.
METHODS
Ultrasound shear wave elastography images were acquired from the PM fiber regions and surface electromyography obtained activity from six shoulder muscles, while 14 BCT participants, 14 SI participants, and 14 age-matched controls remained at rest or generated submaximal shoulder torques.
RESULTS
BCT and SI participants were significantly weaker in shoulder adduction, while BCT participants were also weaker in internal and external rotation (all p ≤ 0.003). PM function was altered following either BCT or SI. In all treatment groups, the clavicular fiber region contributed primarily to flexion, and the sternocostal primarily contributed to adduction. However, healthy participants utilized the clavicular region more during adduction and the sternocostal region more during flexion when compared to BCT or SI participants (all p ≤ 0.049). The still intact clavicular region increased its contributions to flexion torques in SI participants compared to controls (p = 0.016). Finally, BCT and SI participants compensated for changes in PM function using synergistic shoulder musculature.
CONCLUSION
Both BCT and SI breast reconstruction result in significant long-term upper extremity strength deficits. Our results suggest changes to the underlying function of the PM and the adoption of unique but inadequate neuromuscular compensation strategies drive these deficits.
PubMed: 38851662
DOI: 10.1007/s10549-024-07381-z -
Journal of Orthopaedic Surgery and... Jun 2024Existing studies have shown that computed tomography (CT) attenuation and skeletal muscle tissue are strongly associated with osteoporosis; however, few studies have...
BACKGROUND
Existing studies have shown that computed tomography (CT) attenuation and skeletal muscle tissue are strongly associated with osteoporosis; however, few studies have examined whether vertebral HU values and the pectoral muscle index (PMI) measured at the level of the 4th thoracic vertebra (T4) are strongly associated with bone mineral density (BMD). In this study, we demonstrate that vertebral HU values and the PMI based on chest CT can be used to opportunistically screen for osteoporosis and reduce fracture risk through prompt treatment.
METHODS
We retrospectively evaluated 1000 patients who underwent chest CT and DXA scans from August 2020-2022. The T4 HU value and PMI were obtained using manual chest CT measurements. The participants were classified into normal, osteopenia, and osteoporosis groups based on the results of dual-energy X-ray (DXA) absorptiometry. We compared the clinical baseline data, T4 HU value, and PMI between the three groups of patients and analyzed the correlation between the T4 HU value, PMI, and BMD to further evaluate the diagnostic efficacy of the T4 HU value and PMI for patients with low BMD and osteoporosis.
RESULTS
The study ultimately enrolled 469 participants. The T4 HU value and PMI had a high screening capacity for both low BMD and osteoporosis. The combined diagnostic model-incorporating sex, age, BMI, T4 HU value, and PMI-demonstrated the best diagnostic efficacy, with areas under the receiver operating characteristic curve (AUC) of 0.887 and 0.892 for identifying low BMD and osteoporosis, respectively.
CONCLUSIONS
The measurement of T4 HU value and PMI on chest CT can be used as an opportunistic screening tool for osteoporosis with excellent diagnostic efficacy. This approach allows the early prevention of osteoporotic fractures via the timely screening of individuals at high risk of osteoporosis without requiring additional radiation.
Topics: Humans; Female; Osteoporosis; Male; Thoracic Vertebrae; Retrospective Studies; Middle Aged; Tomography, X-Ray Computed; Aged; Bone Density; Absorptiometry, Photon; Pectoralis Muscles; Mass Screening; Aged, 80 and over; Radiography, Thoracic; Adult
PubMed: 38845012
DOI: 10.1186/s13018-024-04825-6 -
Frontiers in Sports and Active Living 2024Unstable surfaces are commonly utilized to enhance the flexibility of the musculoskeletal system for achieving training or rehabilitation goals. However, their effects...
Electromyography of shoulder muscles in individuals without scapular dyskinesis during closed kinetic chain exercises on stable and unstable surfaces: a systematic review and meta-analysis.
INTRODUCTION
Unstable surfaces are commonly utilized to enhance the flexibility of the musculoskeletal system for achieving training or rehabilitation goals. However, their effects on shoulder muscle activation during various push-up (PU) exercises have not been thoroughly investigated. Therefore, the purpose of this study was to synthesize electromyography (EMG) data of shoulder muscles in individuals without scapular dyskinesis performing different PU exercises on both stable and unstable surfaces.
METHODS
A systematic online search was conducted in electronic databases, including Web of Science, PubMed, Scopus, and Google Scholar, up to January 16, 2024, using predefined sets of keywords. Out of the 1,971 titles and abstracts screened, 80 articles were reviewed in detail by two independent researchers to check the eligibility, of which 28 eligible studies were ultimately included. Following assessment of the quality and risk of bias, the studies were categorized based on exercises and muscle groups, and a meta-analysis using a random-effects model was performed to estimate the overall effect size.
RESULTS
The use of unstable surfaces led to a decrease in anterior deltoid activity during PU [ = 0.032; = 91.34%; SMD = -0.630 (95% CI -1.205, -0.055)], an increase in pectoralis major activity during PU [ = 0.006; = 63.72%; SMD = 0.282 (95% CI 0.079, 0.484)], as well as during knee PU [ = 0.018; = 32.29%; SMD = 0.309 (95% CI 0.052, 0.565)], and an increase in triceps brachii activity during PU [ = 0.000; = 85.05%; SMD = 0.813 (95% CI 0.457, 1.168)], knee PU [ = 0.000; = 0.00%; SMD = 0.589 (95% CI 0.288, 0.891)], as well as during push-up plus [ = 0.006; = 13.16%; SMD = 0.563 (95% CI 0.161, 0.965)]. However, the use of unstable surfaces did not show a significant effect on the EMG activity of the pectoralis major during push-up plus [ = 0.312; = 22.82%; SMD = 0.207 (95% CI -0.194, 0.609)].
CONCLUSIONS
Unstable surfaces can modulate muscle activity in different PU exercises, while the effects on the targeted muscles depend on the type of exercise. The findings of this review provide a framework based on the level of activity of each shoulder muscle during different PU exercises, which can help coaches, trainers, and sports therapists select the most suitable type of PU for designing training or rehabilitation programs. Particularly, the most suitable exercise for increasing anterior deltoid activity is PU on a stable surface. To concurrently increase activity of the pectoralis major and triceps brachii, adding unstable surfaces under hands during knee PU and standard PU is recommended.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO, identifier CRD42021268465.
PubMed: 38840951
DOI: 10.3389/fspor.2024.1385693 -
Frontiers in Physiology 2024The objective of this study was to examine the effects of nicotinamide riboside (NR) feeding on high-yield broiler growth and meat quality. Fertilized Cobb 700...
The objective of this study was to examine the effects of nicotinamide riboside (NR) feeding on high-yield broiler growth and meat quality. Fertilized Cobb 700 by-product eggs ( = 3,240) were randomly assigned to one of four in ovo treatments and injected with 0 (), 250 (), 500 (), or 1,000 () mM NR at incubation-day 10. Chicks were hatched, vent sexed, and randomly placed 18 per pen in one of 32 floor pens. On day 48, birds were processed and deboned. There were dose effects for all part weights ( < 0.05). Pectoralis major weight of 250, 500, and 1,000NR carcasses were heavier than 0NR ( < 0.03) but did not differ from remaining NR doses ( > 0.26). Pectoralis minor weight of 250NR carcasses was greater ( < 0.01) than 0NR and did not differ from other NR tenders ( > 0.21). Pectoralis minor weight of 500 and 1,000NR carcasses was greater than 0NR ( < 0.09), but did not differ ( = 0.82) from each other. There were no dose effects for all Pectoralis major and minor myopathy scores and incidence except incidence of tenders scoring "0" and "1" for woody-like tender. Percentage of NR1,000 tenders scoring 0 and 1 for woody-like tender were less than and greater than all other treatments, respectively ( < 0.05). There were no differences among remaining NR doses and NR0 tenders ( > 0.10). There were dose effects for muscle fiber number ( = 0.03). There tended to be more muscle fibers within 250 and 1,000NR muscles compared to 0NR ( < 0.09). Pectoralis major muscle from 500NR did not differ in muscle fiber number compared to 250 and 1,000NR ( > 0.18), but had more ( < 0.01) fibers than 0NR muscle. There tended to be more fibers in 250 and 1,000NR muscles compared to 0NR muscle ( < 0.09). Nicotinamide riboside in ovo feeding caused birds to produce heavier parts; however, myopathy scores and incidence were minimally affected which may have been due greater muscle fiber number.
PubMed: 38835727
DOI: 10.3389/fphys.2024.1397442