GDF5 as a rejuvenating treatment for age-related neuromuscular failure.

Sarcopenia involves a progressive loss of skeletal muscle force, quality and mass during ageing, which results in increased inability and death; however, no cure has been established thus far. Growth differentiation factor 5 (GDF5) has been described to modulate muscle mass maintenance in various contexts. For our proof of concept, we overexpressed GDF5 by AAV vector injection in Tibialis Anterior (TA) muscle of adult aged (20 months) mice and performed molecular and functional analysis of skeletal muscle. We analysed human Vastus Lateralis muscle biopsies from adult young (21-42 years) and aged (77-80 years) donors, quantifying the molecular markers modified by GDF5 overexpression (OE) in mouse muscle. We validated the major effects of GDF5 overexpression using human immortalized myotubes and Schwann Cells (SCs). We established a pre-clinical study by treating chronically (for 4 months) aged mice using recombinant GDF5 protein (rGDF5) in systemic administration and evaluated the long-term effect of this treatment on muscle mass and function. Here, we demonstrated that GDF5 OE in the old TAs promoted an increase of 16.5% of muscle weight (P = 0.0471) associated with a higher percentage of 5000-6000 µm2 large fibres (P = 0.0211), without the induction of muscle regeneration. Muscle mass gain was associated with an amelioration of 26.8% of rate of force generation (P = 0.0330) and a better neuromuscular connectivity (P = 0.0098). Moreover, GDF5 OE preserved neuromuscular junction (NMJ) morphology (38.5% of nerve terminal area increase, P < 0.0001) and stimulated the expression of re-innervation-related genes, in particular markers of SCs (fold change 3.19 for S100b gene expression, P = 0.0101). To further characterize the molecular events induced by GDF5 OE during ageing, we performed a genome-wide transcriptomic analysis of treated muscles and showed that this factor leads to a "rejuvenating" transcriptomic signature in aged mice, as 42% of the transcripts dysregulated by ageing reverted to youthful expression levels upon GDF5 OE (P < 0.05). Towards a pre-clinical approach, we performed a long-term systemic treatment using rGDF5 and showed its effectiveness in counteracting age-related muscle wasting, improving muscle function (17,8% of absolute maximal force increase, P = 0.0079), ensuring neuromuscular connectivity and preventing NMJ degeneration (7,96% of AchR area increase, P = 0.0125). In addition, in human muscle biopsies, we found the same age-related alterations than those observed in mice and improved by GDF5 and reproduced its major effects on human cells, suggesting this treatment as efficient in humans. Overall, these data provide a foundation to examine the curative potential of GDF5 drug in clinical trials for sarcopenia and, eventually, other neuromuscular diseases.

Late Ordovician eurypterid preserves oldest euchelicerate musculature in pyrite.

Pyritization of soft tissues of invertebrates is rare in the fossil record. In New York State, it occurs in black shales of the Lorraine Group (Late Ordovician), the best-known example of which is Beecher's Trilobite Bed. Exceptional preservation at the quarry where this bed is exposed allowed detailed examination of trilobite and ostracod soft-tissue anatomy. Here, we present the first example of a eurypterid (sea scorpion) currently ascribed to Carcinosomatidae from this deposit that also preserves the first evidence for mesosomal musculature in eurypterids. This specimen demonstrates that eurypterid musculature can be preserved in pyrite and evidences the oldest example of euchelicerate muscles within the fossil record. Sulfur isotope data illustrate that pyrite rapidly replicated muscle tissue in the early burial environment, prior to the pyritization of biomineralized exoskeleton and cuticular trilobite limbs. This discovery therefore expands the limited fossil record of euchelicerate musculature, while extending the taphonomic scope for preservation of detailed internal structures, more broadly, within arthropods.

A novel three-part pharynx and its parallel evolution within symbiotic marine nematodes (Desmodoroidea, Stilbonematinae).

Stilbonematinae are nematodes commonly found in shallow marine sands. They are overgrown by a genus- and species-specific coat of chemoautotrophic sulphur-oxidizing ectosymbiotic bacteria which profit from the vertical migration of their hosts through the chemocline by alternately gaining access to oxidizing and reducing chemical species, while in return, the host feeds on its symbionts. The subfamily exhibits a large morphological variability; e.g. the anterior pharynx is cylindrical in genera possessing a voluminous coat, but species with a bacterial monolayer possess a distinctly swollen corpus and therefore a tripartite pharynx. Since 18S-based phylogenetic analyses do not show close relationships between corpus-bearing species, we investigated the pharynx morphology using phalloidin staining in combination with confocal laser scanning microscopy, transmission electron microscopy and light microscopy in order to assess an independent evolution. The class-wide stable position of the subventral pharynx ampullae was used as a morphological marker. Ampullae are positioned at the anterior-most end of the isthmus in Cyathorobbea, further posterior in Catanema and Robbea and inside the corpus in Laxus oneistus. We therefore conclude an independent evolution of corpus enlargements within Stilbonematinae. This further suggests that pharynx morphology is driven by the volume of the symbiotic bacterial coat rather than phylogeny. Based on an existing mathematical model, an enlarged corpus should enable its bearer to ingest food in smaller quantities, in gourmet style, whereas a cylindrical pharynx would restrict its bearer to ancestral gourmand feeding. A review of pharynx types of Nematoda showed that the Stilbonematinae pharynx is substantially different compared to other tripartite pharynges. The lack of pharyngeal tubes and valves, the undivided corpus and evenly distributed nuclei in the isthmus warrant the definition of the "stilbonematoid" three-part pharynx.

Abdominal Etching-A Novel Classification Method for Surgical Approach.

BACKGROUND: The abdomen is the aesthetic and physical center of the body. Abdominal etching is used to enhance the appearance of the abdominal musculature. Body contouring and abdominal etching are popular among both men and women, and these procedures have been shown to result in high patient satisfaction and are considered safe. The aim of this study was to describe a novel classification for abdominal etching based on the senior author's technique and experience. METHODS: This single surgeon, nonrandomized, retrospective study was conducted from December 2016 to September 2022. Patients were classified into 4 groups based on their body habitus, abdominal skin pinch test and skin quality, and the surgical plan was tailored accordingly. RESULTS: Sixty-two patients (42 male) with an average age of 36 years underwent abdominal etching during the study period. Subgrouping included 4 (6.45%) in Class 1, 22 (35.5%) in Class 2, 32 (51.6%) in Class 3 and 4 (6.45%) in Class 4. The most common complication was seroma. Concomitant procedures included silicone implants to the pectoral region (male), fat injection to the buttocks, breast reduction and mastopexy and treatment of post-liposuction irregularities. CONCLUSIONS: The abdominal etching technique is safe and reproducible. It has demonstrated long-lasting results and high patient satisfaction. Our classification of patients will enable surgeons to better understand the problem presented and provide aesthetic and efficient results. Use of these guidelines and tailoring treatment options will further improve patient and physician satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266.

Impact of clear aligner therapy on masticatory musculature and stomatognathic system: a systematic review conducted according to PRISMA guidelines and the Cochrane handbook for systematic reviews of interventions.

BACKGROUND: Clear aligner therapy has gained popularity as a minimally invasive orthodontic treatment option. However, its impact on the masticatory musculature and the stomatognathic system is an area of growing interest, as it involves the adjustment of occlusion and tooth movement. This systematic review aims to comprehensively assess and synthesise existing evidence regarding the influence of clear aligner therapy on the masticatory musculature and the stomatognathic system. METHODS: An exhaustive search was performed on electronic databases that adhered to PRISMA guidelines. Clinical studies that evaluated the impact of patients receiving aligner orthodontic treatment on the muscles of the mastication and stomatognathic systems were included. A standardised data extraction form was devised for relevant variables. Two reviewers extracted the data variables. ROB-2 was used for bias evaluation in the selected studies. RESULTS: A total of six studies met the inclusion criteria. The wearing of clear aligners significantly impacted the muscles of mastication. Muscle activity and discomfort showed a significant alteration in the initial days of appliance placement. but this observation was temporary, with no significant changes thereafter in subsequent follow-up. Bite force reduction was also noted. All the studies evaluated showed good methodological quality. CONCLUSION: The review found that aligned orthodontic treatment may have a variable impact on muscles of mastication, with a potential for initial exacerbation of symptoms followed by possible improvement. However, due to the limited number of studies and their heterogeneous nature, further robust research is recommended to fully understand the relationship between aligned orthodontic treatment and masticatory muscles.

Paraspinal Muscle Changes in Individuals with and without Chronic Low Back Pain over a 4-Month Period: A Longitudinal MRI Study.

Background and Objectives: Previous research has shown associations between atrophy and fatty infiltration of the lumbar paraspinal musculature and low back pain (LBP). However, few studies have examined longitudinal changes in healthy controls and individuals with LBP without intervention. We aimed to investigate the natural variations in lumbar paraspinal musculature morphology and composition in this population over a 4-month period. Materials and Methods: Healthy controls and individuals with LBP were age- and sex-matched and completed several self-administered questionnaires. MRIs of L1-L5 were taken at baseline, 2 months, and 4 months to investigate cross-sectional area (CSA), along with DIXON fat and water images. A total of 29 participants had clear images for at least one level for all three time points. Means and standard deviations were calculated for the participant demographics. A two-way repeated measures ANOVA was performed to investigate CSA, fat signal fraction, and CSA asymmetry. Results: A total of 27 images at L3/L4, 28 images at L4/L5, and 15 images at L5/S1 were included in the final analysis. There were significant main effects of group for psoas CSA at the L3/L4 level (p = 0.02) and erector spinae (ES) CSA % asymmetry at the L3/L4 level (p < 0.001). There was a significant main effect of time for lumbar multifidus (LM) CSA % asymmetry at L4/L5 level (p = 0.03). Conclusions: This study provides insights into LM, ES, and psoas morphology in both healthy controls and affected individuals over a 4-month period without any intervention. Our findings suggest that psoas CSA at higher lumbar levels and CSA % asymmetry in general may be a better indicator of pathology and the development of pathology over time. Evaluating natural variations in paraspinal musculature over longer time frames may provide information on subtle changes in healthy controls and affected individuals and their potential role in chronic LBP.

Musculature of an Early Cambrian cycloneuralian animal.

Cycloneuralians are ecdysozoans with a fossil record extending to the Early Cambrian Fortunian Age and represented mostly by cuticular integuments. However, internal anatomies of Fortunian cycloneuralians are virtually unknown, hampering our understanding of their functional morphology and phylogenetic relationships. Here we report the exceptional preservation of cycloneuralian introvert musculature in Fortunian rocks of South China. The musculature consists of an introvert body-wall muscular grid of four circular and 36 radially arranged longitudinal muscle bundles, as well as an introvert circular muscle associated with 19 roughly radially arranged, short retractors. Collectively, these features support at least a scalidophoran affinity, and the absence of muscles associated with a mouth cone and scalids further indicates a priapulan affinity. As in modern scalidophorans, the fossil musculature, and particularly the introvert circular muscle retractors, may have controlled introvert inversion and facilitated locomotion and feeding. This work supports the evolution of scalidophoran-like or priapulan-like introvert musculature in cycloneuralians at the beginning of the Cambrian Period.

Antidromic and orthodromic reciprocating tachycardias over a novel left-sided accessory pathway involving the vein of Marshall and coronary sinus musculature.

INTRODUCTION: Herein, we present a rare case of the successful ablation of an accessory pathway (AP) involving the Marshall Bundle (MB) and coronary sinus musculature (CSM) in a 40-year-old man with Wolff-Parkinson-White syndrome. METHODS AND RESULTS: An orthodromic reciprocating tachycardia (ORT) was inducible with the earliest atrial activation site located at the posterolateral mitral annulus. The local conduction and the cycle length of ORT was prolonged by peri-mitral ablation; however, it failed to block the AP. The atrial insertion of the AP was identified by remapping during ORT at the left atrial ridge, which was away from the mitral annulus, where ablation was successful. Together with the electrophysiological findings in CSM potentials, we conclude that the epicardial MB-CSM connection functioned as the AP in this patient. CONCLUSION: The novel variant form of AP comprised of MB and CSM should be noted. The atrial insertion of the MB may be the target of catheter ablation.

Comparing male and female pelvic floor muscle function by the number and type of pelvic floor symptoms.

AIMS: Pelvic floor symptoms (PFS), including lower urinary tract symptoms, defecation problems, sexual dysfunction, and pelvic pain, are common in males and females. Comparing pelvic floor musculature (PFM) function between sexes may reveal important differences relevant to clinical care. This study aimed to compare male and female PFM function and to assess the function of both sexes with the number and type of PFS. METHODS: We purposively enrolled males and females aged ≥ 21 years with 0-4 PFS based on questionnaire responses in an observational cohort study. Participants then underwent PFM assessment, and muscle function in the external anal sphincter (EAS) and puborectal muscle (PRM) were compared between sexes. The relationships between muscle function and the number and type of PFS were explored. RESULTS: Of the invited 400 males and 608 females, 199 and 187 underwent PFM assessment, respectively. Compared with females, males more often showed increased EAS and PRM tone during assessments. Compared with males, females more often showed weaker maximum voluntary contraction (MVC) of the EAS and dysfunctional endurance of both muscles; additionally, those with zero or one PFS, sexual dysfunction, and pelvic pain more often showed a weak MVC of the PRM. CONCLUSIONS: Despite a few similarities between males and, females we found differences in muscle tone, MVC, and endurance between male and female PFM function. These findings provide useful insights into the differences in PFM function between males and females.

Magnetic Resonance Imaging of the Lumbar Spine: Recommendations for Acquisition and Image Evaluation from the BACPAC Spine Imaging Working Group.

Management of patients suffering from low back pain (LBP) is challenging and requires development of diagnostic techniques to identify specific patient subgroups and phenotypes in order to customize treatment and predict clinical outcome. The Back Pain Consortium (BACPAC) Research Program Spine Imaging Working Group has developed standard operating procedures (SOPs) for spinal imaging protocols to be used in all BACPAC studies. These SOPs include procedures to conduct spinal imaging assessments with guidelines for standardizing the collection, reading/grading (using structured reporting with semi-quantitative evaluation using ordinal rating scales), and storage of images. This article presents the approach to image acquisition and evaluation recommended by the BACPAC Spine Imaging Working Group. While the approach is specific to BACPAC studies, it is general enough to be applied at other centers performing magnetic resonance imaging (MRI) acquisitions in patients with LBP. The herein presented SOPs are meant to improve understanding of pain mechanisms and facilitate patient phenotyping by codifying MRI-based methods that provide standardized, non-invasive assessments of spinal pathologies. Finally, these recommended procedures may facilitate the integration of better harmonized MRI data of the lumbar spine across studies and sites within and outside of BACPAC studies.

Quantifying the effect of an endo-vaginal probe on position of the pelvic floor viscera and muscles.

INTRODUCTION AND HYPOTHESIS: Endovaginal ultrasound has long been hypothesized to have a significant effect on locations of what it visualizes. However, little work has directly quantified its effect. This study aimed to quantify it. METHODS: This cross-sectional study consisted of 20 healthy asymptomatic volunteers who underwent both endovaginal ultrasound and MRI. The urethra, vagina, rectum, pelvic floor, and pubic bone were segmented in both ultrasound and MRI using 3DSlicer. Then, using 3DSlicer's transform tool the volumes were rigidly aligned based on the posterior curvature of the pubic bone. The organs were then split into thirds along their long axis to compare their distal, middle, and proximal sections. Using Houdini, we compared the location of the centroid of each of the urethra, vagina, and rectum and the surface-to-surface difference of the urethra and rectum. The anterior curvature of the pelvic floor was also compared. Normality of all variables was assessed by Shapiro-Wilk test. RESULTS: The largest amount of surface-to-surface distance was observed in the proximal region for the urethra and rectum. Across all three organs, the majority of the deviation was in the anterior direction for geometries obtained from ultrasound versus those from MRI. For each subject, the trace defining the midline of the levator plate was more anterior for ultrasound compared to MRI. CONCLUSIONS: While it has often been assumed that placing a probe in the vagina probably distorts the anatomy, this study quantified the distortion and displacement of the pelvic viscera. This allows for better interpretation of clinical and research findings based on this modality.

Wear and tear of the intestinal visceral musculature by intrinsic and extrinsic factors.

BACKGROUND: The gut visceral musculature plays essential roles in not only moving substances through the lumen but also maintaining the function and physiology of the gut. Although the development of the visceral musculature has been studied in multiple model organisms, how it degenerates is poorly understood. RESULTS: Here, we employ the Drosophila midgut as a model to demonstrate that the visceral musculature is disrupted by intrinsic and extrinsic factors, such as aging, feeding, chemical-induced tissue damage, and oncogenic transformation in the epithelium. Notably, we define four prominent visceral musculature disruption phenotypes, which we refer as "sprout," "discontinuity," "furcation," and "crossover" of the longitudinal muscle. Given that the occurrence of these phenotypes is increased during aging and under various stresses, we propose that these phenotypes can be used as quantitative readouts of deterioration of the visceral musculature. Intriguingly, administration of a tissue-damaging chemical dextran sulfate sodium (DSS) induced similar visceral musculature disruption phenotypes in zebrafish larvae, indicating that ingestion of a tissue-damaging chemical can disrupt the visceral musculature in a vertebrate as well. CONCLUSIONS: Our study provides insights into the deterioration of the gut visceral musculature and lays a groundwork for investigating the underlying mechanisms in Drosophila as well as other animals.

Musculotendinous system of mesopelagic fishes: Stomiiformes (Teleostei).

Every night the greatest migration on Earth starts in the deep pelagic oceans where organisms move up to the meso- and epipelagic to find food and return to the deeper zones during the day. One of the dominant fish taxa undertaking vertical migrations are the dragonfishes (Stomiiformes). However, the functional aspects of locomotion and the architecture of the musculotendinous system (MTS) in these fishes have never been examined. In general, the MTS is organized in segmented blocks of specific three-dimensional 'W-shaped' foldings, the myomeres, separated by thin sheets of connective tissue, the myosepta. Within a myoseptum characteristic intermuscular bones or tendons may be developed. Together with the fins, the MTS forms the functional unit for locomotion in fishes. For this study, microdissections of cleared and double stained specimens of seven stomiiform species (Astronesthes sp., Chauliodus sloani, Malacosteus australis, Eustomias simplex, Polymetme sp., Sigmops elongatus, Argyropelecus affinis) were conducted to investigate their MTS. Soft tissue was investigated non-invasively in E. schmidti using a micro-CT scan of one specimen stained with iodine. Additionally, classical histological serial sections were consulted. The investigated stomiiforms are characterized by the absence of anterior cones in the anteriormost myosepta. These cones are developed in myosepta at the level of the dorsal fin and elongate gradually in more posterior myosepta. In all but one investigated stomiiform taxon the horizontal septum is reduced. The amount of connective tissue in the myosepta is very low anteriorly, but increases gradually with body length. Red musculature overlies laterally the white musculature and exhibits strong tendons in each myomere within the muscle bundles dorsal and ventral to the horizontal midline. The amount of red musculature increases immensely towards the caudal fin. The elongated lateral tendons of the posterior body segments attach in a highly complex pattern on the caudal-fin rays, which indicates that the posterior most myosepta are equipped for a multisegmental force transmission towards the caudal fin. This unique anatomical condition might be essential for steady swimming during diel vertical migrations, when prey is rarely available.

Paraspinal Muscle in Chronic Low Back Pain: Comparison Between Standard Parameters and Chemical Shift Encoding-Based Water-Fat MRI.

BACKGROUND: Paraspinal musculature (PSM) is increasingly recognized as a contributor to low back pain (LBP), but with conventional MRI sequences, assessment is limited. Chemical shift encoding-based water-fat MRI (CSE-MRI) enables the measurement of PSM fat fraction (FF), which may assist investigations of chronic LBP. PURPOSE: To investigate associations between PSM parameters from conventional MRI and CSE-MRI and between PSM parameters and pain. STUDY TYPE: Prospective, cross-sectional. POPULATION: Eighty-four adults with chronic LBP (44.6 ± 13.4 years; 48 males). FIELD STRENGTH/SEQUENCE: 3-T, T1-weighted fast spin-echo and iterative decomposition of water and fat with echo asymmetry and least squares estimation sequences. ASSESSMENT: T1-weighted images for Goutallier classification (GC), muscle volume, lumbar indentation value, and muscle-fat index, CSE-MRI for FF extraction (L1/2-L5/S1). Pain was self-reported using a visual analogue scale (VAS). Intra- and/or interreader agreement was assessed for MRI-derived parameters. STATISTICAL TESTS: Mixed-effects and linear regression models to 1) assess relationships between PSM parameters (entire cohort and subgroup with GC grades 0 and 1; statistical significance α = 0.0025) and 2) evaluate associations of PSM parameters with pain (α = 0.05). Intraclass correlation coefficients (ICCs) for intra- and/or interreader agreement. RESULTS: The FF showed excellent intra- and interreader agreement (ICC range: 0.97-0.99) and was significantly associated with GC at all spinal levels. Subgroup analysis suggested that early/subtle changes in PSM are detectable with FF but not with GC, given the absence of significant associations between FF and GC (P-value range: 0.036 at L5/S1 to 0.784 at L2/L3). Averaged over all spinal levels, FF and GC were significantly associated with VAS scores. DATA CONCLUSION: In the absence of FF, GC may be the best surrogate for PSM quality. Given the ability of CSE-MRI to detect muscle alterations at early stages of PSM degeneration, this technique may have potential for further investigations of the role of PSM in chronic LBP. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.

Exploring pelvic floor muscle function in men with and without pelvic floor symptoms: A population-based study.

BACKGROUND: Pelvic floor symptoms (PFS), such as lower urinary tract symptoms, defecation disorders, sexual problems, and genital-pelvic pain, are prevalent in men. Thorough physical assessments of the external anal sphincter (EAS) and the puborectal muscle (PRM) are the keys to unraveling the role of muscle dysfunction. OBJECTIVES: To explore associations within and between the EAS and PRM and between muscle (dys-) function and the number of male PFS. METHODS: This cross-sectional study purposively enrolled men aged ≥21 years with 0-4 symptoms from a larger study. After extensive external and internal digital pelvic floor assessment, we explored (1) agreement between muscle function of the EAS versus PRM (using cross tabulation), (2) associations within and between the EAS and PRM (using heatmaps), and (3) associations between muscle function and number of PFS (using a visual presentation [heatmaps] and χ2  tests). RESULTS: Overall, 42 out of 199 men (21%) had completely normal muscle function. Sixty-six (33.2%) had no symptoms, of which 53 (80%) had some degree of muscle dysfunction. No clear dose-response relationship existed between muscle (dys-) function and the number of symptoms. The PRM showed both more dysfunction and severer dysfunction than the EAS. CONCLUSIONS: No clear association exists between muscle dysfunction and the number of symptoms, and the absence of PFS does not indicate normal muscle function for all men. Dysfunction levels are highest for the PRM. Further pelvic floor muscle research is warranted in men with PFS.

Unique Features of River Lamprey (Lampetra fluviatilis) Myogenesis.

The river lamprey (L. fluviatilis) is a representative of the ancestral jawless vertebrate group. We performed a histological analysis of trunk muscle fiber differentiation during embryonal, larval, and adult musculature development in this previously unstudied species. Investigation using light, transmission electron (TEM), and confocal microscopy revealed that embryonal and larval musculature differs from adult muscle mass. Here, we present the morphological analysis of L. fluviatilis myogenesis, from unsegmented mesoderm through somite formation, and their differentiation into multinucleated muscle lamellae. Our analysis also revealed the presence of myogenic factors LfPax3/7 and Myf5 in the dermomyotome. In the next stages of development, two types of muscle lamellae can be distinguished: central surrounded by parietal. This pattern is maintained until adulthood, when parietal muscle fibers surround the central muscles on both sides. The two types show different morphological characteristics. Although lampreys are phylogenetically distant from jawed vertebrates, somite morphology, especially dermomyotome function, shows similarity. Here we demonstrate that somitogenesis is a conservative process among all vertebrates. We conclude that river lamprey myogenesis shares features with both ancestral and higher vertebrates.

Neuromuscular organization and haptoral armament of Polyclithrum ponticum (Monogenea: Gyrodactylidae).

Most gyrodactylids have a haptor armed with a pair of hamuli, two connecting bars and 16 marginal hooks. In some gyrodactylids, however, the haptor is disc-shaped and reinforced by additional sclerites. The genus Polyclithrum has arguably the most elaborate haptor in this group. This study aimed to gain better understanding of the anatomy of Polyclithrum by examining neuromusculature and haptoral armament of Polyclithrum ponticum, a species parasitizing Mugil cephalus in the Black Sea, with emphasis on haptoral sclerites and musculature in connection with host-attachment mechanisms. Musculature was stained by phalloidin, the nervous system by anti-serotonin and anti-FMRFamide antibodies, and haptoral sclerites were visualized in reflected light. The study provided new information on sclerites: in addition to previously described supplementary sclerites (A1-6), ear-shaped sclerites (ESSs) and two paired groups of ribs, reflected light revealed a rod-shaped process on the ESSs and a pair of small posterior sclerites. The sclerites were shown to be operated by 16 muscles, the most prominent of which were two transverse muscles connecting the hamular roots, three muscles attached to sclerite A2, the muscle fibres of anterior ribs and a set of extrinsic muscles. The nervous system consists of a pair of cerebral ganglia connected by a commissure and three pairs of nerve cords that unite in the haptor to form a loop between the opposite cords. The arrangement of sclerites and muscles suggests that Polyclithrum initiates the attachment by clamping a host's surface with longitudinally folded haptor and then secures its position with marginal hooks.

[Transfer of the pronator quadratus to restore opposition of the thumb: An anatomic study and a clinical report]. / Étude anatomique sur le lambeau de carré pronateur pédiculé réinnervé pour réanimer l'opposition du pouce et application clinique.

OBJECTIVE: The purpose of this study is to explore the feasibility of reconstructing the APB with a pedicled PQ flap, and to report results in a child presenting with bilateral radial deficiency. METHODS: Twenty-one injected cadaver upper extremities were dissected. The muscle was pedicled distally on the transverse carpal artery, and reinnervated with the flexor digiti minimi (FDM) motor branch. The transfer was evaluated on 3 parameters: surgical feasibility, length of the distal pedicle and distance from the coaptation site to the muscle entry of recipient nerve. A bilateral PQ pedicled transfer was accomplished in a 17-month old child with bilateral radial deficiency. RESULTS: In the cadaver study, transfer of PQ to the APB was feasible and the distal end of the PQ transfer was reaching the radial side of the first metacarpophalangeal joint in all cases. The length of the distal pedicle on the transverse carpal artery was 38.5±0.20mm. The distance from coaptation of the FDM to the PQ muscle entry was 43.0±3.77mm. At 7 months, there was a cosmetic improvement of the thenar eminence, a bilateral M3 abduction of the thumb and a functional improvement from bilateral PQ pedicled transfer. CONCLUSIONS: Reconstruction of the APB may be achieved with a PQ pedicled transfer reinnervated, improving the function and the cosmetic aspect of the thenar eminence without sacrificing any function of the hand.

Anatomical comparison across heads, fore- and hindlimbs in mammals using network models.

Animal body parts evolve with variable degrees of integration that nonetheless yield functional adult phenotypes: but, how? The analysis of modularity with Anatomical Network Analysis (AnNA) is used to quantitatively determine phenotypic modules based on the physical connection among anatomical elements, an approach that is valuable to understand developmental and evolutionary constraints. We created anatomical network models of the head, forelimb, and hindlimb of two taxa considered to represent a 'generalized' eutherian (placental: mouse) and metatherian (marsupial: opossum) anatomical configuration and compared them with our species, which has a derived eutherian configuration. In these models, nodes represent anatomical units and links represent their physical connection. Here, we aimed to identify: (1) the commonalities and differences in modularity between species, (2) whether modules present a potential phylogenetic character, and (3) whether modules preferentially reflect either developmental or functional aspects of anatomy, or a mix of both. We predicted differences between networks of metatherian and eutherian mammals that would best be explained by functional constraints, versus by constraints of development and/or phylogeny. The topology of contacts between bones, muscles, and bones + muscles showed that, among all three species, skeletal networks were more similar than musculoskeletal networks. There was no clear indication that humans and mice are more alike when compared to the opossum overall, even though their musculoskeletal and skeletal networks of fore- and hindlimbs are slightly more similar. Differences were greatest among musculoskeletal networks of heads and next of forelimbs, which showed more variation than hindlimbs, supporting previous anatomical studies indicating that in general the configuration of the hindlimbs changes less across evolutionary history. Most observations regarding the anatomical networks seem to be best explained by function, but an exception is the adult opossum ear ossicles. These ear bones might form an independent module because the incus and malleus are involved in forming a functional primary jaw that enables the neonate to attach to the teat, where this newborn will complete its development. Additionally, the human data show a specialized digit 1 module (thumb/big toe) in both limb types, likely the result of functional and evolutionary pressures, as our ape ancestors had highly movable big toes and thumbs.

A randomized comparison of training programs using a pelvic model designed to enhance pelvic floor examination in patients presenting with chronic pelvic pain.

INTRODUCTION: Pelvic floor myalgia is a common cause and contributor to chronic pelvic pain [Neurourol Urodyn 4:984-1008 (2017)]. The purpose of this study was to compare in-person versus video-based teaching methods of a comprehensive assessment of the pelvic floor musculature on a pelvic model. METHODS: A randomized controlled trial of 46 participants was conducted. The participants were randomized into two groups. Both groups were taught by the same pelvic floor physiotherapist using two different teaching methods on a pelvic model. Group 1 watched an instructional video, whereas group 2 had in-person training. Both groups underwent pre- and post-training assessments consisting of a written examination and an Objective Structured Clinical Examination (OSCE). Primary outcome measure was the change in participants' pre- and post-training assessment scores. Secondary outcome measures were perceived changes in both participants' comfort level in performing pelvic floor examination and applicability of the training program to clinical practice. RESULTS: There was no statistically significant difference between the teaching methods in the degree of improvement of the participants' mean written assessment scores (p = 0.58), OSCE scores (p = 0.15), and perceived comfort level (p = 0.19). Participants' mean pre- and post-assessment scores improved significantly (p < 0.001). Participants reported the training program to be applicable towards their clinical practice. CONCLUSIONS: This study demonstrates that learners' assessment of pelvic floor musculature can be enhanced using varied teaching methods on a pelvic model.