Adult Leg Research Articles

Long-Term Live Imaging of Drosophila Pupal Leg Development After Puparium Removal.

Over the past decades, significant progress has been made in understanding the mechanisms of cell fate determination. However, the process by which fate-determined cells form three-dimensional organismal shapes remains unclear. Recent advances in confocal microscopy have facilitated efforts to observe cell dynamics during development through live imaging. The Drosophila melanogaster pupa is ideal for live imaging due to its immobility, transparent pupal cuticle, and the availability of fluorescent reporter lines. A primary challenge for imaging is the puparium, the cuticle surrounding the pupa, which obstructs optical imaging. While previous methods involved either partial or complete removal of the puparium, maintaining pupal viability for extended periods after this procedure has remained challenging. Here, a simple method is presented for days-long live imaging of the Drosophila leg during the pupal stage, involving complete puparium removal. The method includes removing the puparium from a pupa adhered to double-sided tape, followed by assembling a small chamber on a glass-bottom dish to enclose the pupa and a drop of water. This setup is straightforward, reliable, and supports extended pupal survival by preventing desiccation. Long-term live imaging of the Drosophila pupa has significantly contributed to capturing how the adult leg undergoes dramatic three-dimensional structural changes over 2-3 days. These changes include the transient formation of an intriguing structure (the Parthenon-like structure) by epithelial cells, rapid tissue narrowing, joint formation, and bristle elongation. This method is applicable to the observation of various tissues and can potentially be combined with other techniques, such as optical gene induction, to advance the understanding of cell dynamics during the final shape formation of tissues in the pupal stage.

Free medial sural artery perforator flap for soft tissue defects in the hand: a cadaver study.

We carried out a cadaver study using 10 fresh-frozen adult legs and hands to explore technical feasibility and reproducibility of the free Medial Sural Artery Perforator flap and its applicability for covering soft tissue defects in the hand. A mean of 2 cutaneous perforators (1-4) were found. Each flap had a pedicle composed of a main perforator that arose from the medial sural artery. Distance between the middle of the popliteal fossa and the emergence of the main perforator was 10 ± 1.9 cm. The pedicle length was 13 ± 1.6 cm. It included an artery (diameter: 2.5 ± 0.6 mm) and a vein (diameter: 3.2 ± 1.2 mm). Skin paddle thickness was 8.5 ± 1.9 mm. Using an 8 x 8 cm skin paddle, it was always possible to cover the entire palmar and dorsal sides of the hand. Our findings suggest that this free flap is a reliable and reproducible option for large cutaneous defects of the hand, offering an effective alternative to conventional flaps. LEVEL OF EVIDENCE: IV.

NompC regulates locomotion and touch sensation in Bactrocera dorsalis.

No mechanoreceptor potential C (NompC) is a major mechanotransduction channel with an important role in sensing of external mechanical stimuli by insects, which help these organisms to avoid injury and adapt to environmental changes. To explore the biological functions of NompC in Bactrocera dorsalis, a notorious agricultural pest, we successfully generated NompC knockout strains using clustered regularly interspaced small palindromic repeats (CRISPR) / CRISPR-associated nuclease 9 (Cas9) technology. BdorNompC knockout led to an adult lethal phenotype, with approximately 100% mortality at 3 d after eclosion. Morphological observation revealed that the legs and wings of BdorNompC knockout insects were deformed, while behavioral assays showed that the locomotion was impaired in both adults and larvae, relative to that of the wild-type strain. Moreover, BdorNompC knockout reduced gentle-touch response in larvae. These results suggest that BdorNompC is critical for B. dorsalis survival, and that this mechanosensation channel represents a potential new target for pest control agents. Our findings also represent novel evidence indicating that insect NompC is involved in modulating adult wing and leg morphology.

Performance of Microsoft Azure Kinect DK as a tool for estimating human body segment lengths

The Microsoft Kinect depth sensor, with its built-in software that automatically captures joint coordinates without markers, could be a potential tool for ergonomic studies. This study investigates the performance of Kinect in limb segment lengths using dual-energy X-ray absorptiometry (DXA) as a reference. Healthy children and adults (n = 76) were recruited for limb length measurements by Kinect and DXA. The results showed consistent ratios of arm, forearm, thigh, and leg lengths to height, which were 0.16, 0.14, 0.23, and 0.22 respectively, for both age groups and methods. Kinect exhibited perfect correlation among all limb lengths, indicating fixed proportions assumed by its algorithm. Comparing the two methods, there was a strong correlation (R = 0.850–0.985) and good to excellent agreement (ICC = 0.829–0.977), except for the right leg in adults, where agreement was slightly lower but still moderate (ICC = 0.712). The measurement bias between the methods ranged from − 1.455 to 0.536 cm. In conclusion, Kinect yields outcomes similar to DXA, indicating its potential utility as a tool for ergonomic studies. However, the built-in algorithm of Kinect assumes fixed limb proportions for individuals, which may not be ideal for studies focusing on investigating limb discrepancies or anatomical differences.

Unveiling the cell dynamics during the final shape formation of the tarsus in Drosophila adult leg by live imaging

Organisms display a remarkable diversity in their shapes. Although substantial progress has been made in unraveling the mechanisms that govern cell fate determination during development, the mechanisms by which fate-determined cells give rise to the final shapes of organisms remain largely unknown. This study describes in detail the process of the final shape formation of the tarsus, which is near the distal tip of the adult leg, during the pupal stage in Drosophila melanogaster. Days-long live imaging revealed unexpectedly complicated cellular dynamics. The epithelial cells transiently form the intriguing structure, which we named the Parthenon-like structure. The basal surface of the epithelial cells and localization of the basement membrane protein initially show a mesh-like structure and rapidly shrink into the membranous structure during the formation and disappearance of the Parthenon-like structure. Furthermore, macrophage-like cells are observed moving around actively in the Parthenon-like structure and engulfing epithelial cells. The findings in this research are expected to significantly contribute to our understanding of the mechanisms involved in shaping the final structure of the adult tarsus.

Molecular Cloning and Expression Profiling of Minus-C Odorant Binding Proteins from Apocheima cinerarius (Lepidoptera: Geometridae)1

Abstract Based on transcriptome data of adults and pupae, 3 Minus-C OBPs (odorant binding proteins) genes were cloned and analyzed in various tissues (including head, thorax, abdomen, legs of female and male adults, and wings of males) of Apocheima cinerarius Erschoff (Lepidoptera: Geometridae). Expression patterns were examined across the developmental stages of egg, larva (1st–5th instars), pupa (non-diapause and diapause), and adults. The qRT-PCR results revealed a significant up-regulation of OBP8 in 3rd and 4th larval instars, with the highest expression level observed in 4th-instar larvae. OBP14 exhibited higher expression levels in diapausing pupal and adult stages, with highest levels in the female adult. Conversely, OBP18 displayed highest expression in the non-diapausing pupae, while exhibiting extremely low expression levels among other stages. The tissue expression profile revealed a gradual increase in the expression of OBP14, with highest levels in the male legs, whereas the expression pattern of OBP18 exhibited an inverse trend with maximum expression observed in the male head (including antennae). OBP8 exhibited high expression levels in the abdomen of the female adult, while OBP14 showed high expression in the legs of the male adult. Additionally, OBP18 displayed high expression in the female head. These findings suggest the crucial role played by OBP genes in both olfactory and non-olfactory tissues of A. cinerarius. The results provide a fundamental basis for further investigation into the recognition of odorant binding in A. cinerarius.

A Historical Overview of the Role of Benzodiazepines including Clonazepam in the Treatment of Adult Restless Legs Syndrome and Periodic Limb Movements in Sleep.

Benzodiazepines are frequently used as therapy in Restless Legs Syndrome (RLS) and Periodic Limb Movements in Sleep. The order of benefit is Sleep>RLS>PLMS and arousals > PLMS. For clonazepam dosages of 0.5 mg-2.0 mg/day are most frequently employed. Benzodiazepines exert their therapeutic effect through GABA-ergic mechanisms.

Symmetric unipedal balance in quiet stance and dynamic tasks in older individuals

Previous evidence of increased difference of muscular strength between the dominant and non-dominant legs in older adults suggests the possibility of dissimilar balance control between the legs (between-leg asymmetry) associated with aging. In the current investigation, we evaluated between-leg asymmetries in older adults when performing quiet and dynamic balance tasks. Fifty-two physically active and healthy older adults within the age range of 60 to 80 years were recruited. Participants performed balance tasks in unipedal stance, including quiet standing and cyclic sway (rhythmic oscillation) of the non-supporting leg in the anteroposterior or mediolateral directions, producing foot displacements with amplitudes of 20 cm paced in 1 Hz through a metronome. Body balance was evaluated through trunk accelerometry, by using the sensors embedded into a smartphone fixed at the height of the 10th-12th thoracic spines. Analysis revealed lack of significant differences in balance control between the legs either when comparing the right versus left or the preferred versus non-preferred legs, regardless of whether they were performing quiet stance or dynamic tasks. Further examination of the data showed high between-leg correlation coefficients (rs range: 0.71–0.84) across all tasks. Then, our results indicated symmetric and associated between-leg balance control in the examined older adults.

Anatomical considerations of the sural nerve in the distal leg: Side branch patterns and significance in nerve harvesting procedures

BackgroundThe sural nerve is a somatosensory nerve that provides sensation to the posterolateral aspect of the lower leg and the lateral part of the ankle and foot. Due to its location and anatomical properties, it is often used as an autologous nerve graft. However, the nerve harvest can be complicated by the presence of side branches. The objective of this study was to investigate the anatomy of the sural nerve and to map its side branches. This information can be used to predict the localization of separate incisions during the stair-step incisions technique for nerve harvest, thereby reducing the risk of complications. MethodsThe study involved the dissection of 50 adult cadaveric legs (25 left and 25 right) obtained from 27 Central European cadavers. The focus of the dissection was to identify the sural nerve, small saphenous vein, and surrounding anatomical structures. Detailed measurements were taken on the side branches of the sural nerve, tributaries of the small saphenous vein, and their interrelationship. ResultsThe average number of sural nerve side branches in a single leg was 4.2±1.9. These side branches were categorized into six groups based on their location and course: mediodistal, medioproximal, lateroproximal, laterodistal, medial perpendicular, and lateral perpendicular. Specific patterns of combination of these side branches were also identified and described. The branching point of the sural nerve was found to be 5.8±2.7 cm proximal to the lateral malleolus, whereas the small saphenous vein branching point was located more distally, 4.5 ± 2.8 cm proximal to the lateral malleolus. The highest density of sural nerve side branches was found 2.1–6.0 cm above the lateral malleolus. ConclusionThis study presents valuable data about the relationship between the sural nerve and the surrounding anatomical structures in the distal part of the leg, including the identification of its side branches and their relevance during nerve harvest procedures. On the basis of the most frequent locations of side branches, a three-incision-technique for nerve harvest is proposed.

Morphological and genetic differences in legs of a polygamous beetle between sexes, Glenea cantor (Coleopter: Cerambycidae: Lamiinae).

The legs of insects play an important role in their daily behaviour, especially reproduction. Entomologists have performed much research on the role of the leg in different behaviours of beetles, an important group in the insect family, but relatively little has been done to study the ultrastructure and transcriptome of their legs. Hence, we systematically studied the ultrastructure and gene expression of the leg of G. cantor, a polygynous beetle, and compared its male and female diversity. In this study, we found the fore-leg, mid-leg and hind-leg of the female were significantly longer than those of the male. From the perspective of intuitive structural differences, we also compared the ultrastructures of the adhesion structure (tarsal) of males and females. The tarsal functional structure of the adult leg mainly includes sensilla and an adhesion structure. The sensilla on the tarsal joint mainly include sensilla chaetica (SCh II, SCh III) and sensilla trichodea (ST II). The adhesion structure includes disc-shaped bristles (di), lanceolate bristles (la), serrated bristles (se), spatula-shaped bristles (spl) and mushroom-shaped bristles (mus). Although there was no significant difference in sensillum distribution or type between males and females, there were significant differences in the distribution and species of adhesion structures between the fore-leg, mid-leg, and hind-leg of the same sex and between males and females. Therefore, different adhesion structures play different roles in various behaviours of beetles. On the other hand, the transcriptome results of male and female legs were screened for a subset of olfaction- and mechanics-related genes. We discovered that the male leg showed upregulation of 1 odorant binding protein (OBP), 2 Olfactory receptors (ORs) and 2 Chemosensory proteins (CSPs). Meanwhile, the female leg showed upregulation of 3 OBPs, 1 OR, 1 Gustatory receptor (GR) and 3 Mechanosensitive proteins (MSPs). An in-depth examination of the ultrastructure and molecular composition of the legs can elucidate its function in the reproductive behavior of G. cantor. Moremore, this investigation will serve as a cornerstone for subsequent research into the underlying behavioral mechanisms.

Development of a Rapid Isothermal Amplification Assay for the Fall Armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), Using Species-Specific Genomic Sequences

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), is native to tropical and subtropical regions of the Western Hemisphere, but is now regularly appearing in crop fields across South Korea, particularly in corn fields. Therefore, it is crucial to promptly and accurately identify the presence of FAW in crop fields to effectively eradicate it as a regulated quarantine species. We developed a loop-mediated isothermal amplification (LAMP) assay, which allows for rapid in-filed identification. To develop the LAMP assay, we selected FAW-specific genomic regions from the whole-genome sequences of one FAW and 13 other lepidopteran species and validated five primer sets that consistently produced positive reactions in ten FAW samples collected from eight different locations in four countries. The assay successfully identified FAW in a maximum of 45 min, starting from crude DNA extraction (~15 min) to diagnosis (30 min) from the following samples, which were deposited outdoors for 30 days: a 1st-instar larva, an adult leg, an adult antenna, and 1/16 and 1/8 of an adult thorax. The five assays can be used selectively or in combination to cross-check and provide further confidence in the in-field diagnosis of FAW.

The Effects of Nine Compounds on Aldehyde-Oxidase-Related Genes in Bactrocera dorsalis (Hendel).

Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) (B. dorsalis) is an important agricultural, major invasive, and quarantine pest that can cause significant damage to the economic value of the fruit and vegetable industry. Male bait is one of the most effective methods of surveying, monitoring, and controlling B. dorsalis. In our study, we constructed cDNA libraries using total RNA extracted independently from the antennae, mouthparts, and thoracic legs of male and female adults and the ovipositors of female adults and screened out four aldehyde-oxidase-related genes (AOX-related), C58800, C66700, C67485, and C67698. Molecular docking predictions showed that eight compounds, including 3,4-dimethoxycinnamyl alcohol, 3,4-dimethoxy-cinnamaldehyde, deet, ethyl N-acetyl-N-butyl-β-alaninate, n-butyl butyrate, n-butyl butyrate, ethyl butyrate, methyl eugenol, and ethyl acetate, could combine with proteins encoded by the four B. dorsalis AOX-related genes. Furthermore, QPCR was performed to confirm that four compounds, including 3,4-dimethoxy cinnamic aldehyde, butyl levulinic acid ethyl ester (mosquito repellent), butyl butyrate, and methyl eugenol, induced significant changes in the AOX-related genes of B. dorsalis. These results provide useful information and guidance for the batch screening of potentially useful compounds and the search for effective attractants of B. dorsalis.

Twist is required for muscle development of the adult legs in Henosepilachna vigintioctopunctata.

Although muscle development has been widely studied in Drosophila melanogaster, it was a great challenge to apply to developmental processes of other insect muscles. This study was focused on the functional characterization of a basic helix-loop-helix transcription factor gene twist in an herbivorous ladybird Henosepilachna vigintioctopunctata. Its transcript (Hvtwist) levels were detected in all developmental stages. RNA interference (RNAi)-aidedknockdown of Hvtwist at the penultimate larval instar stage impaired pupation, and caused a deformed adult in the legs. The tarsi were malformed and did not support the bodies in an upright position. The climbing ability was impaired. Moreover, around 50% of the impaired adults had a malformed elytrum. In addition, they consumed less foliage and did not lay eggs. A hematoxylin-eosin staining of the leg demonstrated that the tibial extensor (TE)and the tibial flexor (TF)muscles were originated from the femurs while levator and depressor muscles of the tarsus (TLand TD) were located in the tibia in the control adults, in which tarsal segments were devoid of muscles. RNAi treatment specific to Hvtwist expression markedly impaired TE and TF muscles in the femurs, and prevented the development of TL and TD muscles in the tibia. Therefore, our findings demonstrate Twist plays a vital role in the myogenesis in H. vigintioctopunctata adult legs.

MiR-188-5p regulates the proliferation and differentiation of goat skeletal muscle satellite cells by targeting calcium/calmodulin dependent protein kinase II beta.

The aim of this study was to reveal the role and regulatory mechanism of miR-188-5p in the proliferation and differentiation of goat muscle satellite cells. Goat skeletal muscle satellite cells isolated in the pre-laboratory were used as the test material. First, the expression of miR-188-5p in goat muscle tissues at different developmental stages was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). In addition, miR-188-5p was transfected into goat skeletal muscle satellite cells by constructing mimics and inhibitors of miR-188-5p, respectively. The changes of differentiation marker gene expression were detected by qPCR method. It was highly expressed in adult goat latissimus dorsi and leg muscles, goat fetal skeletal muscle, and at the differentiation stage of muscle satellite cells. Overexpression and interference of miR-188-5p showed that miR-188-5p inhibited the proliferation and promoted the differentiation of goat muscle satellite cells. Target gene prediction and dual luciferase assays showed that miR-188-5p could target the 3'untranslated region of the calcium/calmodulin dependent protein kinase II beta (CAMK2B) gene and inhibit luciferase activity. Further functional studies revealed that CAMK2B promoted the proliferation and inhibited the differentiation of goat muscle satellite cells, whereas si-CAMK2B restored the function of miR-188-5p inhibitor. These results suggest that miR-188-5p inhibits the proliferation and promotes the differentiation of goat muscle satellite cells by targeting CAMK2B. This study will provide a theoretical reference for future studies on the molecular mechanisms of skeletal muscle development in goats.

Compositional Variations between Adult and Infant Skin Microbiome: An Update.

Human skin and its commensal microbiome form the first layer of protection to the outside world. A dynamic microbial ecosystem of bacteria, fungi and viruses, with the potential to respond to external insult, the skin microbiome has been shown to evolve over the life course with an alteration in taxonomic composition responding to altered microenvironmental conditions on human skin. This work sought to investigate the taxonomic, diversity and functional differences between infant and adult leg skin microbiomes. A 16S rRNA gene-based metataxonomic analysis revealed significant differences between the infant and adult skin groups, highlighting differential microbiome profiles at both the genus and species level. Diversity analysis reveals differences in the overall community structure and associated differential predicted functional profiles between the infant and adult skin microbiome suggest differing metabolic processes are present between the groups. These data add to the available information on the dynamic nature of skin microbiome during the life course and highlight the predicted differential microbial metabolic process that exists on infant and adult skin, which may have an impact on the future design and use of cosmetic products that are produced to work in consort with the skin microbiome.

The effects of single-leg disuse on skeletal muscle strength and size in the nonimmobilized leg of uninjured adults: a meta-analysis.

The effects of single-leg immobilization on changes in skeletal muscle strength and size in the nonimmobilized leg remain controversial. Some studies have shown decreases, or even increases, in skeletal muscle strength and size of the nonimmobilized leg, thus challenging its role as an internal control. Here, we meta-analyze changes in knee extensor strength and size in the nonimmobilized leg of noninjured adults who participated in single-leg disuse studies. We extracted data from the nonimmobilized leg of participants from 15 of 40 studies included in our previous meta-analysis on single-leg disuse. Single-leg disuse had a trivial effect on knee extensor strength (Hedges' gav = -0.13 [-0.23, -0.03], P < 0.01, -3.6 ± 5.6%, N = 13 studies, n = 194 participants) and no impact on knee extensor size (0.06 [-0.06, 0.19], P = 0.21, 0.8 ± 2.9%, N = 9, n = 107) in the nonimmobilized leg. By comparison, single-leg disuse had a large effect on knee extensor strength (-0.85 [-1.01, -0.69], P < 0.01, -20.4 ± 6.4%; mean difference between legs = 16.8 ± 7.8% [12.8, 20.8], P < 0.001) and a medium effect on knee extensor size (-0.40 [-0.55, -0.25], P < 0.01, -7.0 ± 4%; mean difference = 7.8 ± 5.6% [11.6, 4.0], P < 0.002) in the immobilized leg. These results highlight the utility of the nonimmobilized leg to act as an internal control in single-leg immobilization studies.NEW & NOTEWORTHY Our meta-analyses show a trivial effect of single-leg immobilization on leg extensor strength and no effect on leg extensor size in the nonimmobilized leg in uninjured adults. Thus, the nonimmobilized leg in single-leg immobilization studies can serve as useful internal control when examining changes in knee extensor strength and size.

Case study of a special burial resulting from obstetric death at the Sanbulijia site, Shandong Province, China

AbstractMany young women were believed to die due to pregnancy and childbirth in the past, yet few cases of pregnant female burials have been reported in bioarcheological literature. Therefore, this paper reports the burial of an adult female (H49‐1) and her infant (H49‐2), who were buried together in an early Western Zhou pit at the Sanbulijia site, Jiaodong Peninsula, Shandong Province, China. It is the first reported case of obstetric death in thePre‐Qin Period in Shandong Province. The mother–child relationship was proved by ancient DNA evidence and archeological context. The infant's remains were placed between the adult's lower legs. Skeletal histological evidence suggests that the infant died during or shortly after childbirth. Sacroiliac fusion of individual H49‐1 may have resulted in dystocia. Furthermore, a special postmortem burial ritual—pit burial, was carried out for both the infant and the mother. H49 is the first Zhou Dynasty pit burial (multiple burial) with an exact radiocarbon date in the Shandong Peninsula. The case under review suggests that both the adult and the infant may have died due to special events, which may be related to obstetric death.

Long-term Safety, Dose Stability, and Efficacy of Opioids for Patients With Restless Legs Syndrome in the National RLS Opioid Registry.

Restless legs syndrome (RLS) is a sensory-motor neurologic disorder. Low-dose opioids are prescribed for patients with refractory or augmented RLS. The long-term safety, dose stability, and efficacy of these medications for RLS treatment is still unclear. In this study, we report the 2-year longitudinal data in a sample of patients treated with opioids for RLS in the community. The National RLS Opioid Registry is an observational longitudinal study consisting of individuals taking a prescribed opioid for diagnosed and confirmed RLS, most of whom experienced augmented symptoms from dopamine agonists. Information on opioid dosages, side effects, past and current concomitant RLS treatments, RLS severity, psychiatric symptoms, and opioid abuse risk factors was collected at initial Registry entry and every 6 months thereafter by surveys on REDCap. No feedback or intervention was provided by the study staff to local providers. Registry participants (n = 448) with 2-year longitudinal data available were mostly White, female, older than 60 years, and, at Registry entry, had been on opioids for a median of 1-3 years at a mean morphine milligram equivalent (MME) of 38.4 (SD = 43.5). No change in RLS severity in the overall cohort was observed over the 2-year follow-up period. The median change in daily opioid dose from baseline to 2 years was 0 MME (interquartile range = 0-10). While 41.1% of participants increased their dose during the follow-up period (median increase = 10 MME), 58.9% decreased their dose or saw no change. Only 8% and 4% saw increases of >25 MME and >50 MME, respectively. Ninety-five percent of those who increased opioid dose >25 or >50 MME had one of the following features: switching opioids, discontinuation of nonopioid RLS treatment medications, at least mild insomnia at baseline, a history of depression, male sex, younger than 45 years, and opioid use for comorbid pain. Low-dose opioid medications continue to adequately control symptoms of refractory RLS over 2 years of follow-up in most of the participants. A minority of patients did see larger dose increases, which were invariably associated with a limited number of factors, most notably changes in opioid and nonopioid RLS medications and opioid use for a non-RLS condition. Continued longitudinal observations will provide insight into the long-term safety and efficacy of opioid treatment of severe, augmented RLS. This study provides Class IV evidence that opioid doses increase in roughly 40% of patients, in most by small amounts, over a 2-year period when prescribed for adult refractory restless leg syndrome.

Comparison of contraction intensity and perceived intensity between dominant and non-dominant leg in sedentary adults

IntroductionAccurate measurement of isometric contraction intensity is a prerequisite for establishing an exercise program and developing a rehabilitation plan. Despite numerous studies performed previously, there is no research on sedentary populations susceptible to injury during exercise. Additionally, although dominant and non-dominant legs showed differences in muscle properties, the legs were not separately investigated. The purposes of this study were to compare the contraction intensity with target intensity and with perceived intensity across 3 different target intensities in sedentary adults and examine the difference between the dominant and non-dominant leg.MethodsVoluntary isometric contractions were performed with resistance provided by a sling rope and measured with a strain gauge during hip extension. First, maximum voluntary contraction (MVC) was executed; subsequently, submaximal contractions at target intensities (75%, 50%, and 25% of MVC) were randomly performed. Perceived intensity was measured at each target intensity.ResultsHip extension forces were significantly different across the 3 intensities (&lt;i&gt;p&lt;/i&gt; &lt; 0.001), with no significant difference between target intensity and contraction intensity or between perceived intensity and contraction intensity. There was no significant difference between the dominant and non-dominant leg. Bland-Altman analysis of the agreement between perceived and contraction intensities revealed a proportional bias for the values within each target intensity (mean bias: –1.15%, standard deviation of bias: 20.96).ConclusionsSedentary subjects were able to distinguish 3 different contraction intensities. Perceived intensity could statistically significantly predict contraction intensity. However, clinicians should note that under- or overestimation can occur regardless of the level of target intensity.

The morphogen Hedgehog is essential for proper adult morphogenesis in Bombyx mori

The well-known morphogen Hedgehog (Hh) is indispensable for embryo patterning and organ development from invertebrates to vertebrates. The role of Hh signaling pathway has been extensively investigated in the model organism Drosophila melanogaster, whereas its biological functions are still poorly understood in non-drosophilid insects. In the current study, we describe comprehensive investigation of Hh biological roles in the model lepidopteran insect Bombyx mori by using both CRISPR/Cas9-mediated gene ablation and Gal4/UAS-mediated ectopic expression. Direct injection of Cas9 protein and Hh-specific sgRNAs into preblastoderm embryos induced complete lethality. In contrast, Hh mutants obtained by the binary transgenic CRISPR/Cas9 system showed no deleterious phenotypes during embryonic and larval stages. However, mutants showed abnormalities from the pupal stage and most of adult body appendages exhibited severe developmental defects. Molecular analysis focused on wing development reveal that Hh signaling, Imd signaling and Wnt signaling pathways were distorted in Hh mutant wings. Ectopic expression by using the binary Gal4/UAS system induce early larval lethality. On contrary, moderate overexpression of Hh by using a unitary transgenic system resulted in severe defects in adult leg and antenna development. Our data directly provide genetic evidence that Hh plays vital roles in imaginal discs development and proper adult morphogenesis in B. mori.