Protamines and the sperm nuclear basic proteins Pandora's Box of insects

Insects are the largest group of animals when it comes to the number and diversity of species. Yet, with the exception of Drosophila, no information is currently available on the primary structure of their sperm nuclear basic proteins (SNBPs). This paper represents the first attempt in this regard and provides information about six species of Neoptera: Poecillimon thessalicus, Graptosaltria nigrofuscata, Apis mellifera, Nasonia vitripennis, Parachauliodes continentalis, and Tribolium castaneum. The SNBPs of these species were characterized by acetic acid urea gel electrophoresis (AU-PAGE) and high-performance liquid chromatography fractionated. Protein sequencing was obtained using a combination of mass spectrometry sequencing, Edman N-terminal degradation sequencing and genome mining. While the SNBPs of several of these species exhibit a canonical arginine-rich protamine nature, a few of them exhibit a protamine-like composition. They appear to be the products of extensive cleavage processing from a precursor protein which are sometimes further processed by other post-translational modifications that are likely involved in the chromatin transitions observed during spermiogenesis in these organisms.

Favorite Parts of a Single Leaf for Giant Flying Squirrels to Eat in Three Species of Food Trees

To examine the effect of leaf chemical composition on selective herbivory by the Japanese giant flying squirrels (Petaurista leucogenys), we measured and compared the total phenolic, glucose, and water contents of leaves among their main food tree species, deciduous Quercus acutissima, and evergreen Q. sessilifolia and Phonitia serratifolia. Leaves of these three tree species were available in the warm season (April to October), but the flying squirrels mostly preferred the leaves of Q. acutissima, having higher glucose and water contents than those of the other two tree species. In the cold season (November to the next March), the two evergreen tree species were available, and the flying squirrels used both leaves without any apparent influence of the chemical compositions. On the other hand, the favorite parts of a single leaf differed among the three tree species. Flying squirrels dropped the individual leaves after partial consumption. Their feeding marks on the dropped leaves were distinguished into four types: apical, basal, central, and marginal parts of consumption. The basal parts of consumption were most frequent in Q. acutissima leaves in which more water was contained at the basal part, and the central part consumption followed, which may be related to a lower phenolic content and more glucose and water at the leaf center than its margin. In contrast, the apically consumed leaves dominated in Q. sessilifolia, with relatively homogeneous leaf chemical distribution except for more water at the center. In P. serratifolia, leaves consumed at the center were frequent, but those with marginal consumption were also observed, which may be related to its specific chemical distribution with less phenolics and more glucose at the leaf margin. Thus, the chemical distributions within the single leaf differ among tree species, and the flying squirrel's selectivity of the tree species and the part of each leaf depends partly on the relative compositions of preferable glucose and water and unpreferable phenolics.

Retarded Diffusion and Confinement of Membrane-Bound Molecules in a Patterned Hybrid Membrane of Phospholipid Bilayers and Monolayers

The biological membrane is a complex two-dimensional fluid, in which various molecular interactions regulate the lateral diffusion of membrane-associated molecules. Pinning of membrane proteins or lipids by extra-membrane proteins impedes the diffusion. In addition, coupling between two monolayer leaflets within a phospholipid bilayer via interdigitation plays important roles, though this effect remains elusive. Here, we fabricate a substrate-supported model membrane with patterned bilayer/monolayer regions to explore the influences of interleaflet coupling. A patterned monolayer of polymerized diacetylene phospholipid, 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DiynePC), was lithographically generated and used to form patterned lipid bilayers and monolayers. A phospholipid monolayer was formed on top of the polymerized monolayer. The bilayer/monolayer hybrid membrane was continuous and fluid, but lateral diffusion in the monolayer region was significantly retarded, suggesting the influences of interleaflet coupling. We reconstituted photoreceptor rhodopsin (Rh) and G-protein transducin (G_t) as model transmembrane and peripheral proteins. Rh diffused laterally only in the bilayer region, whereas G_t diffused in both bilayer and monolayer regions. The patterned hybrid bilayer/monolayer membrane reproduces the retarded diffusion and confinement of membrane-bound molecules in a controlled manner and provides insight into the physicochemical and functional roles of semipermeable corrals in the cell membrane.

Adults of Alderflies, Fishflies, and Dobsonflies (Megaloptera) Expel Meconial Fluid When Disturbed

Chemical secretions are an effective means by which insects may deter potential enemies, already being studied extensively with regard to their chemicals, synthesis, toxicity, and functions. However, these defensive secretions have been little studied in Megaloptera. Herein, the fluid expelling behavior of adult alderflies (Sialidae), fishflies (Corydalidae: Chauliodinae), and dobsonflies (Corydalidae: Corydalinae), all of the order Megaloptera, is described in detail regarding the timing and possible function of this behavior. When disturbed artificially, both males and females could expel fluid from the anus. However, the frequency of expelling was much lower in alderflies than in fishflies and dobsonflies. The amount of expelled fluid relative to body weight was also smaller in alderflies. In fishflies and dobsonflies, the amount of expelled fluid decreased with adult age, probably because the fluid is little replenished once expelled. The cream-colored fluid seems to be meconial fluid produced via the Malpighian tubules at the pupal stage, which is usually discharged at adult emergence in most other holometabolous insects. However, adult fishflies and dobsonflies often expel it vigorously by bending their abdomen when disturbed after emergence. Thus, the fluid expelling may be an anti-predatory behavior, particularly in younger adults that can expel a relatively large amount of fluid.

Pupal Warning Coloration of Three Species of Cystidia (Lepidoptera: Geometridae: Ennominae) in Relation to Their Pupation Sites

Many insects display a cryptic color to avoid detection by predators that search for prey by sight. However, some species with chemicals that predators dislike may display a warning color (aposematism) to predators. The predators can learn easier that the species is unsuitable as prey if the color is more conspicuous. Therefore, it is assumed that the acquisition of the warning color requires not only unpalatability, but also exposure of the color to predators and the ability of predators to recognize and learn it unpalatable. In the moths of the subfamily Ennominae, almost all of genera produce uniformly brown or green pupae, but the pupae of the genus Cystidia have conspicuous coloration of yellow background and black spots. In this study, to clarify whether the color of these pupae is the warning color or not, we compared the coloration, pupation site, and palatability among the three species of this genus: C. couaggaria, C. truncangulata, and C. stratonice. Learning by the predators was also examined using lizards as a potential predator of the moths. The results showed that all three species were repelled (unpalatable) by the lizards, and that repeated providing of the pupae to the lizards decreased their willingness to prey on them (probably due to learning). Pupation sites of C. couaggaria and C. truncangulata were located on the surface of branches and leaves high above the ground, whereas C. stratonice pupated in the space of leaves spun with course silk at lower site above the ground. Thus, the conspicuous coloration of pupal Cystidia is considered to be a warning color, but the pupae of C. stratonice are more blackish than those of the most closely related C. truncangulata. The pupal color of C. stratonice is likely to have a dual meaning as cryptic and warning colors. The dark colored pupa may be inconspicuous when hidden within the leaf space, but once detected by the predators, the yellow color of the pupa may function as a warning color.

Nowcasting Japan's GDP

This paper backtests a nowcast of Japan's real GDP growth. It has three contributions: (i) use of genuine real-time data, (ii) implementation of a new method for the revision analysis that relates the revision of the nowcast to not only new observations but also data revisions, and (iii) a benchmarking of the nowcast to a market consensus forecast at monthly forecasting horizons. Our nowcast's forecast accuracy is comparable to that of the consensus at most, but not all, monthly horizons. Our revision analysis of the March 2011 earthquake finds the nowcast reacting to a steep post-quake decline in car production. In contrast, the consensus hardly budged, most likely because the decline was correctly viewed as temporary. The onset of COVID-19 triggers the consensus to take a precipitous descent. The nowcast, despite timely red flags from "soft" (i.e., survey-based) indicators, does not respond immediately in full, because it took a month or more for "hard" (i.e., non-survey-based) indicators to register sharply reduced economic activities.

Functions of Egg-Coating Substances Secreted by Female Accessory Glands in Alderflies, Fishflies and Dobsonflies (Megaloptera)

Eggs of insects are immobile and must endure harsh environmental conditions (e.g., low temperatures in winter and aridity in summer) and avoid attack by egg-eating predators, egg parasites, and microbes. Females of Megaloptera lay their eggs as a single- or multi-layered egg mass, which is coated with chemical substances secreted from the female reproductive accessory glands. In this study, we observed the egg masses laid by females of two species of Sialidae (alderflies), nine species of Chauliodinae (fishflies), and 23 species of Corydalinae (dobsonflies) belonging to the order Megaloptera and examined the functions of accessory gland substances coating the laid eggs. The female accessory gland is a single tube in alderflies and fishflies but a paired pouch in dobsonflies. The amount and color of the gland substances differ greatly among species. These substances prevent egg desiccation, inhibit egg feeding by ladybird beetles, and repel ants. Most characteristics of the egg mass structures and the effectiveness of accessory gland substances reflect the phylogeny of Megaloptera, although some differ among closely related taxa.

Nanofluidic Model Membrane for the Single-Molecule Observation of Membrane Proteins

Membrane proteins play essential roles in the cell, and they constitute one of the most important targets of drugs. Studying membrane proteins in a controlled model membrane environment can provide unambiguous, quantitative information on their molecular properties and functions. However, reconstituting membrane proteins in a model system poses formidable technological challenges. Here, we developed a novel model membrane platform for highly sensitive observation of membrane proteins by combining a micropatterned lipid membrane and a nanofluidic channel. A micropatterned model membrane was generated by lithographically integrating a polymerized lipid bilayer and a natural (fluid) lipid bilayer. A nanofluidic channel having a defined thickness was formed between the fluid bilayer and a polydimethylsiloxane (PDMS) slab by attaching the polymeric bilayer and PDMS slab using an adhesion layer composed of silica nanoparticles that are coated with a biocompatible polymer brush. As we reconstituted rhodopsin (Rh), a G-protein-coupled receptor (GPCR), from a detergent-solubilized state into the fluid bilayer, only successfully reconstituted Rh molecules diffused laterally in the lipid bilayer and migrated into the nanogap junction, where they could be observed with a vastly improved signal-to-background ratio. The nanogap junction effectively separates the sites of reconstitution and observation and provides a novel platform for studying the molecular properties and functions of membrane proteins at the single-molecular level.

Myofibroblasts are increased in the dorsal layer of the hypertrophic ligamentum flavum in lumbar spinal canal stenosis

BACKGROUND CONTEXT

Hypertrophy of the ligamentum flavum (LF) is a major contributor to the development of lumbar spinal canal stenosis (LSS). Although previous studies have identified some factors related to hypertrophy of the LF, the etiology remains unclear. It is well known that myofibroblasts have a key role in the pathology of fibrosis in other tissues, including the skin, liver, kidney, and lung. We hypothesized that myofibroblasts were also important players in the pathology of fibrosis in the LF.

PURPOSE

To elucidate the distribution and role of myofibroblasts in the hypertrophic LF.

STUDY DESIGN

A histological, immunohistochemical, and gene expression analysis of the LF in the human lumbar spine.

PATIENT SAMPLE

Hypertrophic LF tissue samples were collected from patients with LSS.

OUTCOME MEASURES

Histology, immunohistochemistry, microarray, reverse transcription-quantitative polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay.

METHODS

The degree of fibrosis in the dural and dorsal layers of the LF was evaluated by Masson's trichrome tissue staining. Collagen gene expression was evaluated by quantitative reverse transcription polymerase chain reaction. Immunostaining of αSMA was performed to evaluate localization of myofibroblasts in LF tissue. The association between gene expression of alpha-smooth muscle actin (αSMA) and that of several types of collagen was investigated. The signal activated on the dorsal side of LF was examined by gene set enrichment analysis using microarray data. Expression levels of αSMA and several types of collagen in LF fibroblasts were investigated under hypoxic conditions.

RESULTS

In the histological study using Masson's trichrome staining, the fibrosis score was significantly higher in the dorsal layer than in the dural layer. Gene expression levels for several types of collagen (COL1A1, COL1A2, COL3A1, COL5A1, COL6A1, and COL11A1) and heat shock protein 47 (a collagen-specific chaperone) were significantly higher in the dorsal layer. Furthermore, immunohistochemistry revealed a significantly greater number of αSMA-stained cells in the dorsal layer. There was a strong correlation of αSMA mRNA expression with COL1A-1 in LF fibroblasts. Gene set enrichment analysis showed that the set of fibrosis-related gene signals, including those for epithelial-mesenchymal transition, hypoxia, and inflammation, were significantly upregulated in the dorsal layer compared with the dural layer. Under hypoxic stimulation, expression of αSMA and several types of collagen was increased in LF fibroblasts.

CONCLUSIONS

This study is the first to reveal that myofibroblast expression levels are higher in the dorsal layer of the LF than in the dural layer. We confirmed that hypertrophy of the LF in LSS is associated with increased expression of myofibroblasts in the dorsal layer. Hypoxia could be a cause of expression of myofibroblasts leading to fibrosis and finally to hypertrophy of the LF.

CLINICAL SIGNIFICANCE

The results of this study partially elucidate the molecular mechanisms of LF hypertrophy and suggest that myofibroblasts may be involved in age-related degeneration of the LF.

Toxicity of internalized polyalanine to cells depends on aggregation

In polyalanine (PA) diseases, the disease-causing transcription factors contain an expansion of alanine repeats. While aggregated proteins that are responsible for the pathogenesis of neurodegenerative disorders show cell-to-cell propagation and thereby exert toxic effects on the recipient cells, whether this is also the case with expanded PA has not been studied. It is also not known whether the internalized PA is toxic to recipient cells based on the degree of aggregation. In this study, we therefore prepared different degrees of aggregation of a peptide having 13 alanine repeats without flanking sequences of PA disease-causative proteins (13A). The aggregated 13A was spontaneously taken up by neuron-like cultured cells. Functionally, strong aggregates but not weak aggregates displayed a deficit in neuron-like differentiation in vitro. Moreover, the injection of strong but not weak 13A aggregates into the ventricle of mice during the neonatal stage led to enhanced spontaneous motor activity later in life. Thus, PA in the extracellular space has the potential to enter adjacent cells, and may exert toxicity depending on the degree of aggregation.

Similar pattern, different paths: tracing the biogeographical history of Megaloptera (Insecta: Neuropterida) using mitochondrial phylogenomics

The sequential breakup of the supercontinent Pangaea since the Middle Jurassic is one of the crucial factors that has driven the biogeographical patterns of terrestrial biotas. Despite decades of effort searching for concordant patterns between diversification and continental fragmentation among taxonomic groups, increasing evidence has revealed more complex and idiosyncratic scenarios resulting from a mixture of vicariance, dispersal and extinction. Aquatic insects with discreet ecological requirements, low vagility and disjunct distributions represent a valuable model for testing biogeographical hypotheses by reconstructing their distribution patterns and temporal divergences. Insects of the order Megaloptera have exclusively aquatic larvae, their adults have low vagility, and the group has a highly disjunct geographical distribution. Here we present a comprehensive phylogeny of Megaloptera based on a large-scale mitochondrial genome sequencing of 99 species representing >90% of the world genera from all major biogeographical regions. Molecular dating suggests that the deep divergence within Megaloptera pre-dates the breakup of Pangaea. Subsequently, the intergeneric divergences within Corydalinae (dobsonflies), Chauliodinae (fishflies) and Sialidae (alderflies) might have been driven by both vicariance and dispersal correlated with the shifting continent during the Cretaceous, but with strikingly different and incongruent biogeographical signals. The austral distribution of many corydalids appears to be a result of colonization from Eurasia through southward dispersal across Europe and Africa during the Cretaceous, whereas a nearly contemporaneous dispersal via northward rafting of Gondwanan landmasses may account for the colonization of extant Eurasian alderflies from the south.

Functional Reconstitution of Dopamine D2 Receptor into a Supported Model Membrane in a Nanometric Confinement

Dopamine D2 receptor (D2R), a G-protein-coupled receptor (GPCR), plays critical roles in neural functions and represents the target for a wide variety of drugs used to treat neurological diseases. However, its fundamental physicochemical properties, such as dimerization and affinity to different lipid environments, remain unknown. Here, reconstitution and characterization of D2R in a supported model membrane in nanometric confinement are reported. D2R is expressed in Chinese hamster ovary (CHO) cells and transferred into the supported model membrane as cell membrane blebs. D2R molecules are reconstituted with an elevated density in the cleft between the substrate and poly(dimethylsiloxane) (PDMS) elastomer. Reconstituted D2R retains the physiological functions, as evaluated from its binding to an antagonist and dimerization lifetime. The transient dimer formation of D2R, similar to the live cell, suggests that it is an innate property that does not depend on the cellular structures such as actin filaments. Although the mechanism of this unique reconstitution process is currently not fully understood, the finding points to a new possibility of using a nanometric space (<100 nm thick) as a platform for reconstituting and studying membrane proteins under the quasi-physiological conditions, which are difficult to be created by other methods.

Defensive spray by a semiaquatic osmylid larva (Insecta: Neuroptera) for both aquatic and terrestrial predators

Chemical secretions are an effective means by which insects can deter potential enemies. Several terrestrial insects spray these liquids directionally toward enemies, but little is known about spraying behavior in aquatic and semiaquatic insects. The larvae of Osmylus hyalinatus (Neuroptera: Osmylidae) are semiaquatic, inhabiting the edges of small streams and ponds where they encounter multiple enemies on land and in water. The larvae of this osmylid sprayed a hyaline liquid from the anal opening if disturbed in either air and water, although the spray appeared slightly viscous in water. The liquid was stored in the posterior half of the hindgut and sprayed directionally toward an artificial stimulus. Spraying allowed the larvae to escape biting by ants, and to repel them in 90% of encounters. Spraying caused the regurgitation of 71% and 60% of all larvae swallowed by terrestrial frogs and aquatic newts, respectively. Aquatic fishfly larvae released 30% of captured larvae due to spraying. Most of the larvae that repelled ants or were regurgitated by amphibians survived, but those released by fishfly larvae were killed by heavy biting with the mandibles. This is the first report of effective liquid spraying by insects in water, and also within the order Neuroptera.

Direct measurement of radiation exposure dose to individual organs during diagnostic computed tomography examination

Ionizing radiation from Computed tomography (CT) examinations and the associated health risks are growing concerns. The purpose of this study was to directly measure individual organ doses during routine clinical CT scanning protocols and to evaluate how these measurements vary with scanning conditions. Optically stimulated luminescence (OSL) dosimeters were surgically implanted into individual organs of fresh non-embalmed whole-body cadavers. Whole-body, head, chest, and abdomen CT scans were taken of 6 cadavers by simulating common clinical methods. The dosimeters were extracted and the radiation exposure doses for each organ were calculated. Average values were used for analysis. Measured individual organ doses for whole-body routine CT protocol were less than 20 mGy for all organs. The measured doses of surface/shallow organs were higher than those of deep organs under the same irradiation conditions. At the same tube voltage and tube current, all internal organ doses were significantly higher for whole-body scans compared with abdominal scans. This study could provide valuable information on individual organ doses and their trends under various scanning conditions. These data could be referenced and used when considering CT examination in daily clinical situations.

The effects of phospholipids and fatty acids on the oligomer formation of NAP-22

Recovery of various signal transduction molecules in the detergent-resistant membrane microdomain (DRM) fraction suggests the importance of this region in cellular functions. NAP-22 (also called BASP1 or CAP-23) is a neuron-enriched calmodulin-binding protein and one of the major proteins in the DRM fraction of the neuronal cell membrane. Previous studies showed tight binding activity of NAP-22 to acidic membrane lipids and the self-interaction of NAP-22, i.e., oligomerization. In this study, the effect of various phospholipids, lysophospholipids and fatty acids on the oligomerization of NAP-22 was studied through SDS-PAGE after chemical cross-linking and electron microscopic observation. High molecular mass oligomers were detected by SDS-PAGE after incubation in solutions containing over 20 mM NaCl at pH 6.5-8.5, even in the absence of lipid addition, and the addition of Ca²⁺/calmodulin abolished oligomerization. Higher molecular mass oligomer formation after incubation with acidic phospholipids was detected with gradient SDS-PAGE. Much higher mass oligomers were detected in the presence of polyunsaturated fatty acids. Electron microscopic analysis of the samples after SDS treatment showed tangled rope-like structures. Liposome-bound NAP-22 showed small oval or annular structures after cross-linking and SDS treatment. These oligomers were suggested to make the tangled rope-like structures, for annular structures of the same size were observed in the structure. These results suggest the participation of NAP-22 to liquid-liquid phase separation through oligomerization.

Surgical Treatment of Lumbar Herniated Nucleus Pulposus Combined with Residual Bony Fragment of Apophyseal Ring Fracture in High-Level Athletes : A Report of Two Cases

In this paper, we present 2 cases of herniated nucleus pulposus (HNP) combined with the residual bony fragment of apophyseal ring fracture. HNP typically exists at the narrow lateral recess formed by the bony fragment, and so it has been reported that symptoms may persist. Case 1 was a 22-year-old man, a high-level javelin thrower and Paralympic athlete. He had a history of persistent pain for 4 years due to HNP, and so we performed surgical removal. Case 2 was a 23-year-old male professional baseball player. He was referred to us only 17 days after the onset of pain and presented with muscle weakness, a feature which may prolong the clinical course in addition other features such as pain. Thus, we performed a comparatively quick intervention of surgical removal. In both cases, we had excellent clinical outcomes and better function and performance. In conclusion, in cases with HNP and apophyseal ring separation, surgical intervention in the comparatively early phase can be recommended, particularly if the patients desire quick return to their original level of activity. J. Med. Invest. 66 : 358-361, August, 2019.

Affinity of rhodopsin to raft enables the aligned oligomer formation from dimers: Coarse-grained molecular dynamics simulation of disk membranes

The visual photopigment protein rhodopsin (Rh) is a typical G protein-coupled receptor (GPCR) that initiates the phototransduction cascade in retinal disk membrane of rod-photoreceptor cells. Rh molecule has a tendency to form dimer, and the dimer tends to form rows, which is suggested to heighten phototransduction efficiency in single-photon regime. In addition, the dimerization confers Rh an affinity for lipid raft, i.e. raftophilicity. However, the mechanism by which Rh-dimer raftophilicity contributes to the organization of the higher order structure remains unknown. In this study, we performed coarse-grained molecular dynamics simulations of a disk membrane model containing unsaturated lipids, saturated lipids with cholesterol, and Rh-dimers. We described the Rh-dimers by two-dimensional particle populations where the palmitoyl moieties of each Rh exhibits raftophilicity. We simulated the structuring of Rh in a disk for two types of Rh-dimer, i.e., the most and second most stable Rh dimers, which exposes the raftophilic regions at the dimerization-interface (H1/H8 dimer) and two edges away from the interface (H4/H5 dimer), respectively. Our simulations revealed that only the H1/H8 dimer could form a row structure. A small number of raftophilic lipids recruited to and intercalated in a narrow space between H1/H8 dimers stabilize the side-by-side interaction between dimers in a row. Our results implicate that the nano-sized lipid raft domains act as a “glue” to organize the long row structures of Rh-dimers.

The Origin of the Anterior Lateral Malleolar Artery From the Anterior Tibial Artery: A Fresh Cadaveric Study

The anterior lateral malleolar artery (ALMA), which usually originates from the anterior tibial artery (ATA), courses transversely and laterally, passing under the extensor digitorum longus and peroneus tertius tendons. Variations in the origin of the ALMA from the ATA can occur. Branches of the ATA, such as the ALMA, are prone to pseudoaneurysm. This study reviewed the origin of the ALMA from the ATA and aimed to identify problems in anterior ankle arthroscopy that might cause injury to the ALMA. Enhanced computed tomography scans of 24 feet of 24 fresh cadavers (13 males, 11 females; average age 78.1 years) were assessed. The limb was injected with barium sulfate suspension through the external iliac artery; the origin of the ALMA from the ATA on the sagittal plane was recorded. The origin was at the ankle joint level in 4 specimens and below the ankle joint in 17 specimens. The distance from the ankle joint to the branching point of the ALMA on the sagittal plane was 5.2 mm distal to the joint. The level of origin of the ALMA from the ATA was established. Instruments should not be inserted from the distal direction when placing anterolateral portals. Levels of Evidence: Level IV, cadaveric study.

First description of the larvae of the fishfly genus Anachauliodes Kimmins, 1954 (Megaloptera: Corydalidae: Chauliodinae)

Anachauliodes Kimmins, 1954 (Megaloptera: Corydalidae: Chauliodinae) is a fishfly genus endemic to the Oriental Region with only one recognized species, Anachauliodes laboissierei (Navás, 1913). Currently, the immature stages of this genus are completely unknown. Here we describe the larvae of A. laboissierei for the first time. The larval characters, especially the strongly developed respiratory tubes on the abdominal segment VIII, support a close relationship between Anachauliodes and the eastern Nearctic Chauliodes Latreille, 1796.

Self-Spreading of Phospholipid Bilayer in a Patterned Framework of Polymeric Bilayer

Phospholipid bilayers spontaneously spread on a hydrophilic substrate such as glass in aqueous solution due to the energetic gain of surface wetting. This process (self-spreading) was utilized to form a patterned model biological membrane containing reconstituted membrane proteins. A mechanically stable framework of a polymerized lipid bilayer was first generated by the lithographic polymerization of a diacetylene phospholipid. Then, natural lipid membranes (fluid bilayers) were introduced into the channels between polymeric bilayers by the self-spreading from a phospholipid reservoir. The spreading velocity could be fitted into a slope of -0.5 in a double logarithmic plot versus time due to the balance between the spreading force and resistive drag. The preformed polymeric bilayer accelerated the spreading by the energetic gain of covering hydrophobic edges with a lipid bilayer. At the same time, the domains of the polymeric bilayer obstructed spreading, and the spreading velocity linearly decreased with their fractional coverage. Above the critical coverage of ca. 50%, self-spreading was completely blocked (percolation threshold) and the fluid bilayer was confined in the polymer-free regions. Nonspecific adsorption of lipids onto the surface of polymeric bilayers was negligible, which enabled a heightened signal-to-background ratio in the reconstitution and observation of membrane proteins. Self-spread bilayers had a higher density of lipids than those formed by the spontaneous rupture of vesicles (vesicle fusion), presumably due to the continual supply of lipid molecules from the reservoir. These features give the self-spreading important advantages for preparing patterned model membranes with reconstituted membrane proteins.

P2623Measurement of liver fibrosis marker: type IV collagen 7S among patients with acute heart failure and its relationship with the Enhanced Liver Fibrosis (ELF) score

Background

Hemodynamic disturbance in acute heart failure (HF) can cause injury to extra-cardiac organs such as the liver. Organ injury in HF might evoke a profibrotic response, which could adversely affect the prognosis.

Methods

Among 189 patients with acute HF, we simultaneously determined the liver fibrosis marker, type IV collagen 7S (P4NP 7S) and the Enhanced Liver Fibrosis (ELF) Score consisting of tissue inhibitor of metalloproteinases 1 (TIMP-1), amino-terminal propeptide of type III procollagen (PIIINP) and hyaluronic acid (HA) on admission and at discharge.

Results

During hospitalization, P4NP 7S and ELF score significantly decreased from 7.1 ng/mL to 6.1 ng/mL (P<0.001) and 10.39 to 10.13 (P<0.001), respectively. P4NP 7S and ELF score were correlated with each other on admission (r=0.4, P<0.001) and at discharge (r=0.4, P<0.001). %Change of (Δ) P4NP 7S during hospitalization was correlated with ΔBNP and ΔELF score (r=0.3, P<0.001 and r=0.4, P<0.001, respectively). Among the components of ELF score, PIIINP and HA were correlated with P4NP 7S on admission (r=0.5, P<0.001 and r=0.3, P<0.001, respectively) and at discharge (r=0.4, P<0.001 and r=0.3, P<0.001, respectively). ΔP4NP 7S was also correlated with ΔTIMP-1, ΔPIIINP and ΔHA (r=0.3, P<0.001, r=0.4, P<0.001 and r=0.3, P<0.001, respectively). Each patient was followed up up to 365 days after discharge. 69 patients died or were hospitalized for HF. When the patients were divided into two groups according to the median value of each marker at discharge, the cumulative 1-year incidences of all cause death or HF hospitalization were 32.0% and 45.5% in P4NP 7S-low and P4NP 7S-high group, respectively (log-rank P=0.051) and 43.2% and 34.9% in ELF score-low and ELF score-high group, respectively (log-rank P=0.44). After adjustment by the clinically relevant factors including age, sex, hemoglobin, sodium and left ventricular ejection fraction, P4NP 7S showed independent prognostic value (adjusted hazard ratio: 1.12, P=0.02), while ELF score did not (adjusted hazard ratio: 1.04, P=0.79).

Conclusion

Parallel elevation of P4NP 7S and ELF score were documented during acute phase of HF. P4NP 7S at discharge may identify patients at high risk for subsequent HF related events.

Transforaminal full-endoscopic lumbar discectomy under local anesthesia in awake and aware conditions: the inside-out and outside-in techniques

PURPOSE OF THE REVIEW

Transforaminal full-endoscopic lumbar discectomy (TELD) under local anesthesia was first introduced in Japan in 2003. Initially referred to as percutaneous endoscopic discectomy, in 2018, a consensus was reached worldwide and the preferred term is now TELD. The procedure requires only an 8-mm skin incision and causes minimal damage to the paravertebral muscles. Thus, it is the least invasive disc surgery. In this review, we introduce two types of the TELD surgery.

RECENT FINDINGS

Initially, TELD was performed as the "inside-out" technique but was associated with reports of postoperative dysesthesia due to exiting nerve injury. Recently, the "outside-in" technique after foraminoplasty was proposed for safer insertion of the cannula into the disc. Foraminoplasty can widen the narrow foramen, thereby allowing the 8-mm cannula to pass through easily and safely, and thus injury to the exiting nerve root can be theoretically avoided. We described two types of the TELD in this review. Surgeons should be familiar with the inside-out and outside-in techniques for TELD; therefore, we can select appropriate technique for each case.

Raftophilic rhodopsin-clusters offer stochastic platforms for G protein signalling in retinal discs

Rhodopsin is a G protein-coupled receptor (GPCR) that initiates the phototransduction cascade in retinal disc membrane. Recent studies have suggested that rhodopsin forms highly ordered rows of dimers responsible for single-photon detection by rod photoreceptors. Dimerization is also known to confer to rhodopsin a high affinity for ordered lipids (raftophilicity). However, the role of rhodopsin organization and its raftophilicity in phototransduction remains obscure, owing to the lack of direct observation of rhodopsin dynamics and distribution in native discs. Here, we explore the single-molecule and semi-multimolecule behaviour of rhodopsin in native discs. Rhodopsin forms transient meso-scale clusters, even in darkness, which are loosely confined to the disc centre. Cognate G protein transducin co-distributes with rhodopsin, and exhibits lateral translocation to the disc periphery upon activation. We demonstrate that rhodopsin offers inherently distributed and stochastic platforms for G protein signalling by self-organizing raftophilic clusters, which continually repeat generation/extinction in the disc membrane.

Allometry and morphological trait relationship in the sexually dimorphic Chinese dobsonfly, Acanthacorydalisasiatica (Wood-Mason, 1884) (Megaloptera, Corydalidae)

Male insects with large weapons such as horns and elongate mandibles would be expected to invest more on such structures than other parts of the body for advantages in male to male competition for mating. In male genitalia, however, intermediate size provides a better fit for more females than small or large sizes, and such a male would leave more offspring regardless of their body size. These predictions were tested using a static allometry analysis between body size and other trait sizes. Acanthacorydalisasiatica is a large dobsonfly (Megalotera) and males have conspicuously large mandibles used as weapons. We examined the hypothesis that the male mandibles of this sexually dimorphic species are sexually selected to enlarge, whereas the male genitalia are stable to be intermediate regardless of a great variation in body size. The results, as predicted, showed positive allometry between male body size and mandible length but negative allometry between male body size and ectoproct length (a male grasping structure). Sperm are transferred through a small spermatophore attached externally to the female genital opening, so it may be evolutionarily unnecessary to develop an enlarged male genital size. In contrast, there may be a trade-off between male mandible size and wing length, because of negative allometry between body size and wing length in males but isometry between them in females.

Direction and location of the nutrient artery to the fifth metatarsal at risk in osteotomy for bunionette

BACKGROUND

The aims of this study were to identify the artery feeding the fifth metatarsal and determine how bunionette osteotomy could injure this vessel.

METHODS

The nutrient artery entering the fifth metatarsal was investigated in 10 adult cadaveric lower limbs by barium injection and enhanced computed tomography.

RESULTS

The nutrient artery entered the medial aspect of the fifth metatarsal around the junction of the middle and proximal thirds obliquely from a distal direction (mean angle 36°) in the coronal plane in all cases; in the axial plane, the point of entry and direction of the artery was medial-plantar (mean angle 49°).

CONCLUSIONS

This report revealed direction and location of the nutrient artery entering the fifth metatarsal.

Examination of the Origin and Branching Direction of the Anterior Medial Malleolar Artery From the Anterior Tibial Artery: A Cadaveric Study

BACKGROUND

This study characterized the anterior medial malleolar artery (AMMA) branching from the anterior tibial artery (ATA) to identify problems in anterior ankle arthroscopy possibly contributing to injury to the AMMA.

METHODS

Barium was injected into 12 adult cadaveric feet via the external iliac artery and the origin and branching direction of the AMMA were identified on computed tomography.

RESULTS

The AMMA originated from the level of the ankle joint and below and above the ankle joint line (AJL) in 4 (33.3%), 6 (50.0%), and 1 (8.3%) specimen, respectively. Mean distance from the AJL to the branching point of the AMMA on the sagittal plane was 2.5 mm distal to the AJL. Mean angle between the distal longitudinal axis of the ATA and AMMA was 83.2°.

CONCLUSIONS

This study established the origin and branching of the AMMA from the ATA. The AMMA should be examined carefully during ankle arthroscopy.

LEVELS OF EVIDENCE

Level IV: Cadaveric study.

Distances from the deep plantar arch to the lesser metatarsals at risk during osteotomy: a fresh cadaveric study

Background

The deep plantar arch is formed by anastomosis of the lateral and deep plantar arteries. Osteotomy of the lesser metatarsals is often used to treat metatarsalgia and forefoot deformity. Although it is known that some blood vessels supplying the lesser metatarsals are prone to damage during osteotomy, there is little information on the distances between the deep plantar arch and the three lesser metatarsals. The aims of this study were to identify the distances between the deep plantar arch and the lesser metatarsals and to determine how osteotomy could damage the arch.

Methods

Enhanced computed tomography scans of 20 fresh cadaveric feet (male, n = 10; female, n = 10; mean age 78.6 years at the time of death) were assessed. The specimens were injected with barium via the external iliac artery, and the distance from the deep plantar arch to each lesser metatarsal was measured on axial and sagittal images.

Results

The shortest distances from the deep plantar arch to the second, third, and fourth metatarsals in the axial plane were 0.5, 2.2, and 2.8 mm, respectively. The shortest distances from the distal epiphysis to a line passing through the deep plantar arch perpendicular to the longitudinal axis of the lesser metatarsal in the sagittal plane were 47.0, 45.7, and 46.4 mm, respectively, and those from the tarsometatarsal joint were 23.0, 21.0, and 18.6 mm. The deep plantar arch ran at the level of the middle third, within the proximal portion of this third in 11/20 (55.0%), 7/20 (35.0%), and 5/16 (31.2%) specimens, respectively, and at the level of the proximal third in 9/20 (45.0%), 13/20 (65.0%), and 11/16 (68.8%).

Conclusions

Overpenetration into the medial and plantar aspect of the second metatarsal or the proximal and plantar aspect of the fourth metatarsal during shaft or proximal osteotomy could easily damage the deep plantar arch. Shaft or proximal osteotomy approximately 45-47 mm proximal to the distal epiphysis or 18-23 mm distal to the tarsometatarsal joint on the plantar aspect could interrupt blood flow in the deep plantar arch.

Anatomic Study of Anterior and Posterior Ankle Portal Sites for Ankle Arthroscopy in Plantarflexion and Dorsiflexion: A Cadaveric Study in the Japanese Population

Arthroscopy is an important and minimally invasive diagnostic and therapeutic tool. However, the risk of injury to the neurovascular structures around the portals exists during arthroscopy of the ankle. In the present study, we measured the distance between each portal and the adjacent neurovascular structures with the foot in plantarflexion and dorsiflexion in the Japanese population. Standard anterolateral (AL), anteromedial, posterolateral (PL), and posteromedial portal positions were identified in 6 fresh adult cadaveric feet. The skin was dissected from the underlying tissue to visualize the adjacent neurovascular structures as noninvasively as possible. The superficial peroneal nerve was the structure closest to an anterior (i.e., AL) portal (3.2 ± 4.2 and 8.3 ± 3.9 mm in plantarflexion and 5.2 ± 4.3 and 10.8 ± 4.1 mm in dorsiflexion), followed by the saphenous nerve and great saphenous vein (SpV). The distance from the superficial peroneal nerve to the AL portal and from the saphenous nerve and great SpV to the anteromedial portal increased significantly with dorsiflexion and decreased significantly with plantarflexion. The sural nerve was the structure closest to the posterior (i.e., PL) portal (10.4 ± 4.8 mm in plantarflexion and 8.5 ± 3.9 mm in dorsiflexion), followed by the lesser SpV. The distance from the sural nerve, saphenous nerve, and lesser SpV to the PL portal and from flexor hallucis longus, posterior tibial artery, and tibial nerve to the posteromedial portal increased significantly in plantarflexion and decreased significantly in dorsiflexion. These findings could help to prevent damage to the neurovascular structures during ankle arthroscopy.

Successful Endoscopic Surgery for L5 Radiculopathy Caused by Far-Lateral Disc Herniation at L5-S1 and L5 Isthmic Grade 2 Spondylolisthesis in a Professional Baseball Player

Background

We report the case of a professional baseball player who had severe leg pain due to lumbar lateral disc herniation at L4-5 and isthmic spondylolisthesis at L5 (double crash syndrome). For early recovery to competitive level, we performed minimally invasive endoscopic decompression surgery without fusion. There are few reports to discuss the usefulness of minimally invasive treatment for top athletes.

Methods

A 29-year-old professional baseball player who played catcher was referred to us with a complaint of right leg pain. The previous doctor diagnosed far-lateral disc herniation and Grade 2 isthmic spondylolisthesis and recommended arthrodesis at L5-S1 as treatment for both pathologies. Radiological imaging showed that the right L5 nerve root was impinged by the 2 lumbar disorders, namely, far-lateral disc herniation and a ragged edge around a pars defect. We had taken into account the patient's occupation and his wish to avoid a lengthy sick leave, and we had performed endoscopic decompression surgery during the offseason. The far-lateral disc herniation at L5-S1 was removed under local anesthesia by percutaneous endoscopic discectomy, after which the ragged edge at the pars defect was removed under general anesthesia using a microendoscopic discectomy system. Given that the patient did not have any low back pain, arthrodesis was not considered.

Results

The leg pain resolved after surgery. The following year (2015), the patient resumed playing baseball from the beginning of the season and played in 41 games. In the 2016 season, he played in 71 games without any symptoms. No further slippage was observed at radiological follow up 1 year after the surgery.

Conclusions

Minimally invasive endoscopic surgery is an option for radiculopathy in very active patients who need an early return to their previous level of physical activity.

Role of Epiligament in Ligamentum Flavum Hypertrophy in Patients with Lumbar Spinal Canal Stenosis:a Pilot Study

Ligamentum flavum (LF) hypertrophy is one of the main factors of lumbar spinal canal stenosis (LSCS). The primary object of this study is to clarify the existence of epiligament in the LF and its role in hypertrophy, and to develop an LF hypertrophy animal model. A cadaveric spine from a 30-year-old man was used to investigate the existence of epiligament in LF. Five LF samples from LSCS patients were obtained to evaluate hypertrophied LF. To create a rat model, we destabilized the lumbar spine. Each LF was sagittally cut for histological evaluation. The epiligament was clearly evident in normal LF specimens, which stained pink on Elastica van Gieson and green on Masson Trichrome. One layer was observed on the dural side and another on the dorsal side of the LF. LSCS patients had an enlarged dorsal epiligament, at around 30 times that of the regular thin epiligament on the dural side. The destabilized rat model showed an enlarged dorsal epiligament, with a mean thickness 8-fold that of the control. LF hypertrophy may be due to enlargement of the dorsal epiligament. Mechanical loading of the LF is an important factor for inducing hypertrophy in the rat model. J. Med. Invest. 65:85-89, February, 2018.

Entry points of nutrient arteries at risk during osteotomy of the lesser metatarsals: a fresh cadaveric study

Background

Osteotomies of the lesser (second to fourth) metatarsals are often used to correct forefoot deformities. However, certain areas of the lesser metatarsals where arteries may be prone to damage during surgery, and the resulting nonunion and delayed union could cause serious problems. This study sought to identify the nutrient arteries of the lesser metatarsals and to determine how osteotomy could injure these vessels.

Methods

Enhanced computed tomography scans of 21 ft (male, n = 10; female, n = 11; mean age 78.6 years at the time of death) were assessed. Twenty-one lower limbs in 21 cadaveric specimens were injected with barium via the external iliac artery, and the points at which the nutrient arteries entered the lesser metatarsals were identified on axial and coronal images.

Results

Each nutrient artery entered the lateral or medial plantar aspect of the lesser metatarsal in the middle third (just proximal to the middle point of the metatarsal) or proximal third obliquely from a distal direction. The mean ± standard deviation (SD) distances from the dorsal plane of the second, third, and fourth metatarsals to the point of entry of the nutrient artery in the axial plane were 8.2 ± 1.5, 7.6 ± 1.2, and 7.6 ± 1.5 mm, respectively. The mean ± SD distances from the distal epiphysis to the point of entry of the nutrient artery into the second, third, and fourth metatarsals in the coronal plane were 3.3 ± 1.1, 3.1 ± 1.0, and 2.8 ± 1.2 mm, respectively. The mean ± SD distances from the distal epiphysis to the point of entry of the nutrient artery into the second, third, and fourth metatarsals in the coronal plane were 46.0 ± 5.2, 40.9 ± 2.6, and 39.1 ± 3.7 mm, respectively. The mean ± SD distances from the proximal epiphysis to the entry point of the nutrient artery into the second, third, and fourth metatarsals in the coronal plane were 23.8 ± 4.7, 25.8 ± 4.3, and 25.0 ± 3.2 mm, respectively.

Conclusions

Distal metatarsal osteotomies might be safer than shaft or proximal osteotomy to avoid disruption of the nutrient artery, leading to delayed consolidation of the osteotomy and nonunion.

Platelet-rich plasma does not reduce skeletal muscle fibrosis after distraction osteogenesis

Background

Skeletal muscle fibrosis caused by an increase in collagen deposition often occurs after distraction osteogenesis. Although studies are available reporting the effects of platelet-rich plasma (PRP) on tissue healing following injury, current findings remain controversial. This study focused on determining whether PRP reduces skeletal muscle fibrosis caused by distraction osteogenesis.

Methods

Tibial osteotomies were performed on 8-week-old wild type mice, and tibiae were distracted at a rate of 0.42 mm/day for 2 weeks, starting 1 week after osteotomy. Immediately after distraction was completed (3 weeks after osteotomy), PRP or phosphate buffered saline (as a sham) was injected into the gastrocnemius (GC) muscle. The GC muscles were harvested and analyzed.

Results

The amount and area of collagenous tissue increased in both the PRP and control groups following distraction osteogenesis, but the changes were not significantly different between both groups at all time points (p = 0.89, 0.45, 0.33 and 0.52 at 4, 6, 8 and 10 weeks).

Conclusion

From this study, our results suggest that PRP did not significantly reduce skeletal muscle fibrosis due to distraction osteogenesis.

Inhibitory effect of several sphingolipid metabolites on calcineurin

Neurons have well-developed membrane microdomains called "rafts" that are recovered as a detergent-resistant membrane microdomain fraction (DRM). NAP-22 is one of the major protein components of neuronal DRM. In a previous study, we showed that DRM-derived NAP-22 binds ganglioside and the inhibitory effect of ganglioside to calcineurin (CaN), a neuron-enriched calmodulin-regulated phosphoprotein phosphatase. Considering the important roles of CaN in neurons, identification of other cellular regulators of CaN could be a good clue to understand the molecular background of neuronal function. In this study, we screened the effect of several membrane lipid-derived molecules on the CaN activity and found sphingosine and some sphingosine-derived metabolites such as sphingosylphosphorylcholine, galactosylsphingosine (psychosine), and glucosylsphingosine, have inhibitory effect on CaN through the interaction with calmodulin.

Utility of STIR-MRI in Detecting the Pain Generator in Asymmetric Bilateral Pars Fracture: A Report of 5 Cases

Lumbar spondylolysis usually occurs as a stress fracture in the pars interarticularis of the vertebra. It is a prevalent sports-related disorder and a common cause of low back pain. We encountered five athletes (4 males, 1 female) with severe low back pain. Mean age was 14.5 years. All five patients were found to have bilateral pars fracture. In all cases, staging based on the findings from computed tomography scan of the right and left pars fracture was different. On short tau inversion recovery magnetic resonance imaging (STIR-MRI) of the comparatively newer more recently injured side, high signal intensity changes were obvious and dominant at the intra- and extraosseous area, which would indicate tissue edema and/or bleeding. Furthermore, the imaging findings corresponded to the side of the low back pain. In conclusion, STIR-MRI can effectively distinguish between painful pars fracture and painless pars fracture.

Comparison of Ankle Joint Visualization Between the 70° and 30° Arthroscopes: A Cadaveric Study

Ankle arthroscopy is an important diagnostic and therapeutic tool. Arthroscopic ankle surgery for anterior ankle impingement or osteochondral lesions (OCLs) is mostly performed with a 30° arthroscope; however, visualization of lesions is sometimes difficult. This study sought to compare ankle joint visualization between 70° and 30° arthroscopes and clarify the effectiveness of 70° arthroscopy. Standard anterolateral and anteromedial portals were placed with 4-mm 70° or 30° angled arthroscopes in a fresh 77-year-old male cadaveric ankle. The medial ligament and surrounding tissue were dissected via a medial malleolar skin incision. Kirschner wires were inserted into the distal tibia anterior edge; 5-mm diameter OCLs were created on the medial talar gutter anteriorly, midway, and posteriorly. The talar dome and distal tibia anterior edge were visualized using both arthroscopes. The 70° arthroscope displayed the anterior edge of the distal tibia immediately in front of the arthroscope, allowing full visualization of the posterior OCL of the medial talar gutter more clearly than the 30° arthroscope. This study revealed better ankle joint visualization with the 70° arthroscope, and may enable accurate, safe, and complete debridement, especially in treatment of medial talar gutter posterior OCLs and removal of anterior distal tibial edge bony impediments.

LEVELS OF EVIDENCE

Level IV, Anatomic study.