Fiber Layer Research Articles

Characterization and potential of periosteum-derived cells: an overview.

As a thin fibrous layer covering the bone surface, the periosteum plays a significant role in bone physiology during growth, development and remodeling. Over the past several decades, the periosteum has received considerable scientific attention as a source of mesenchymal stem cells (MSCs). Periosteum-derived cells (PDCs) have emerged as a promising strategy for tissue engineering due to their chondrogenic, osteogenic and adipogenic differentiation capacities. Starting from the history of PDCs, the present review provides an overview of their characterization and the procedures used for their isolation. This study also summarizes the chondrogenic, osteogenic, and adipogenic abilities of PDCs, serving as a reference about their potential therapeutic applications in various clinical scenarios, with particular emphasis on the comparison with other common sources of MSCs. As techniques continue to develop, a comprehensive analysis of the characterization and regulation of PDCs can be conducted, further demonstrating their role in tissue engineering. PDCs present promising potentials in terms of their osteogenic, chondrogenic, and adipogenic capacities. Further studies should focus on exploring their utility under multiple clinical scenarios to confirm their comparative benefit over other commonly used sources of MSCs.

Characterization of myosin heavy chain (MYH) genes and their differential expression in white and red muscles of Chinese perch, Siniperca chuatsi

Fish skeletal muscle is composed of two anatomically and functionally different fiber layers, white or fast and red or slow muscles. Myosin, the major structural protein of fish skeletal muscle, contains multiple myosin heavy chain (MYH) isoforms involved in the high plasticity of muscle in response to varying functional demands and/or environmental changes. In this study, we comparatively assayed the cellular and ultrastructural feature of white and red skeletal muscles. Then, a total of 28 class II myosin heavy chain genes were identified in by searching the Chinese perch genome database. Among them, 14 genes code for the fast-muscle-type myosin heavy chain, and 7 genes code for the slow-muscle-type myosin heavy chain. Further, the different isoform gene structures, function domains, phylogenetic relations, and muscle-fiber type-specific expression were characterized. This is the first systematic work on the molecular characterization of class II myosin heavy chain isoforms and the differential analysis of their expression in red and white muscle tissues in Chinese perch Siniperca chuatsi. Our work provided valuable information for a better understanding of myh genes and their molecular characteristics, and the correlations of multiple myosin isoforms with potential functions in response to varying functional demands and/or environmental changes.

Crushing behavior of CFRP/AL hybrid tubes under oblique lateral loading

AbstractThis work aims to research the oblique lateral crushing behavior of CFRP/AL hybrid tubes under different parameter configurations. First, a finite element model was established based on the maximum stress criterion and the traction‐separation law. The reliability of the numerical models for pure aluminum, pure composite, and hybrid tubes was verified by rigorous comparison with experimental data, respectively. Second, the influence of loading conditions and geometric characteristics on crashworthiness were studied. The results show that the damage modes of the hybrid tube under oblique lateral loading are mainly concentrated in the horizontal and vertical ends, specifically in the form of plastic hinge and fiber, matrix fracture. The CFRP layers has positive effect on improving the specific energy absorption (SEA). High ratio thickness of aluminum tubes can effectively improve the energy absorption (EA) and crush force efficiency (CFE). It is found that the sandwich structure is not conducive to resist lateral crushing, while the CFRP without external constraints can absorb more impact energy.Highlights The oblique lateral crushing behavior of CFRP/AL hybrid tube was studied. A numerical simulation method was proposed and verified. The effects of loading angle, fiber layers and AL thickness were studied. The hybrid ratio and hybrid method were designed and discussed.

Detection of Mast Cells in Human Superficial Fascia.

The recent findings showed that the superficial fascia is a fibrous layer in the middle of hypodermis, richly innervated and vascularized, and more complex than so far demonstrated. This study showed the presence of mast cells in the superficial fascia of the human abdomen wall of three adult volunteer patients (mean age 42 ± 4 years; 2 females, 1 male), by Toluidine Blue and Safranin-O stains and Transmission Electron Microscopy. Mast cells are distributed among the collagen bundles and the elastic fibers, near the vessels and close to the nerves supplying the tissue, with an average density of 20.4 ± 9.4/mm2. The demonstration of the presence of mast cells in the human superficial fascia highlights the possible involvement of the tissue in the inflammatory process, and in tissue healing and regeneration processes. A clear knowledge of this anatomical structure of the hypodermis is fundamental for a good comprehension of some fascial dysfunctions and for a better-targeted clinical practice.

A drug-incorporated-microparticle-eggshell-membrane-scaffold (DIMES) dressing: A novel biomaterial for localised wound regeneration

Chronic wounds affect millions of people annually and have emotional and financial implications in addition to health issues. The current treatment for chronic wounds involves the repeated use of bandages and drugs such as antibiotics over an extended period. A cost-effective and convenient solution for wound healing is the development of drug-incorporated bandages. This study aimed to develop a biocompatible bandage made of drug-incorporated poly (lactic-co-glycolic acid) (PLGA) microparticles (MPs) and eggshell membrane (ESM) for cornea wound healing. ESM has desirable properties for wound healing and can be isolated from eggshells using acetic acid or ethylenediaminetetraacetic acid (EDTA) protocols. Fluorescein isothiocyanate-labelled Bovine Serum Albumin (FITC-BSA) was used as a model drug, and the PLGA MPs were fabricated using a solvent extraction method. The MPs were successfully attached to the fibrous layer of the ESM using NaOH. The surface features of the ESM samples containing MPs were studied using a field emission scanning electron microscope (FESEM) and compared with blank ESM images. The findings indicated that the MPs were attached to the ESM fibres and had similar shapes and sizes as the control MPs. The fibre diameters of the MPs samples were assessed using Fiji-ImageJ software, and no significant changes were observed compared to the blank ESM. The surface roughness, Ra values, of the MPs incorporated ESM samples were evaluated and compared to the blank ESM, and no significant changes were found. Fourier transform infrared (FTIR) spectroscopy was used to analyse the chemical Composition of the bandage, and the spectra showed that the FBM were effectively incorporated into the ESM. The FTIR spectra identified the major peaks of the natural ESM and the PLGA polymer in the bandage. The bandage was transparent but had a reduced visibility in the waterproof test card method. The bandage achieved sustained drug release up to 10 days and was found to be biocompatible and non-toxic in a chorioallantoic membrane (CAM) assay. Overall, the drug-incorporated PLGA MPs-ESM bandage has great potential for treating chronic wounds.

Interspecies comparison of temporomandibular joint condylar cartilage extracellular matrix from macro to microscopy

Interspecies comparisons of the extracellular matrix of temporomandibular joint (TMJ) condylar cartilage are necessary to elucidate the mechanisms underlying its superior mechanical properties, to guide the construction of animal models of TMJ-related diseases, and to establish standards for the engineering of TMJ condylar cartilage. Here we characterize and compare TMJ condylar cartilage from six different species from a materials science perspective, including structure, composition and mechanical properties from the macroscopic to the microscopic level. The gross morphology showed obvious interspecies differences in size and shape, which may be related to the different joint motion patterns. Although the condylar cartilage of all species can be divided histologically into a superficial fibrous layer and a deep hyaline layer, there are significant interspecies differences in the microstructure of the fibrils in the two layers, mainly in the diameter of the fibrils. Compositionally, there were no significant differences in collagen composition between species, but the content of glycosaminoglycans (GAGs) decreased progressively with increasing body size, with the same results obtained by Safranin O staining and biochemical analysis. Mechanically, the elastic modulus of mouse condylar cartilage was significantly higher than that of the other species and tended to decrease with increasing body size. This study shows that the TMJ condylar cartilage of different species has its own specific structure-composition-mechanics matching characteristics for their unique masticatory stress dissipation, and differences in fibril diameter and GAGs content may be the two ultimate factors influencing the differences in cartilage mechanical properties between species, while the condylar cartilage of pigs is most similar to that of humans, suggesting that pigs may be a suitable animal model for TMJ studies.

Recent Advances in Smart Epidural Spinal Needles.

Lumbar puncture is a minimally invasive procedure that utilizes a spinal needle to puncture the lumbar epidural space to take a sample from the cerebrospinal fluid or inject drugs for diagnostic and therapeutic purposes. Physicians rely on their expertise to localize epidural space. Due to its critical procedure, the failure rate can reach up to 28%. Hence, a high level of experience and caution is required to correctly insert the needle without puncturing the dura mater, which is a fibrous layer protecting the spinal cord. Failure of spinal anesthesia is, in some cases, related to faulty needle placement techniques since it is blindly inserted. Therefore, advanced techniques for localization of the epidural space are essential to avoid any possible side effects. As for epidural space localization, various ideas were carried out over recent years to provide accurate identification of the epidural space. Subsequently, several methodologies based on mechanical and optical schemes have been proposed. Several research groups worked from different aspects of the problem, namely, the clinical and engineering sides. Hence, the main goal of this paper is to review this research with the aim of remedying the gap between the clinical side of the problem and the engineering side by examining the main techniques in building sensors for such purposes. This manuscript provides an understanding of the clinical needs of spinal needles from an anatomical point of view. Most importantly, it discusses the mechanical and optical approaches in designing and building sensors to guide spinal needles. Finally, the standards that must be followed in building smart spinal needles for approval procedures are also presented, along with some insight into future directions.

Microstructure Evolution of the Near-Surface Deformed Layer and Corrosion Behavior of Hot Rolled AA7050 Aluminum Alloy.

The current study investigates the influence of hot rolling on the microstructure evolution of the near-surface region on AA7050 aluminum alloy and the corrosion performance of the alloy. It is revealed that hot rolling resulted in grain refinement in the near-surface region, caused by dynamic recrystallization, and equiaxed grains less than 500 nm can be clearly observed. Fibrous grains were evident in the hot rolled AA7050 aluminum alloy with relatively lower rolling temperature or larger rolling reduction, caused by the more severe elemental segregation at grain boundaries, which inhibited the progression of dynamic recrystallization. The density of the precipitates in the fibrous grain layer was higher, compared with those in the equiaxed grain layer, due to the increased dislocation density, combined with more severe elemental segregation, which significantly promoted the nucleation of precipitates. With the co-influence exerted by low density of precipitates and dislocations on the improvement of the corrosion performance of the alloy, the rolled AA7050 alloy with decreased density of precipitates and dislocations exhibited better corrosion resistance.

The dorsal portion of the bovine diaphragm as a useful tissue for producing a 3D muscle scaffold.

Three-dimensional (3D) organoids are an innovative approach to obtain an in vitro model for ex vivo studies to overcome the limitations of monolayer cell culture and reduce the use of animal models. An organoid of skeletal muscle requires the presence of the extracellular matrix to represent a functional muscle in vitro, which is why decellularized tissue is an optimal choice. Various muscles have been considered to produce a muscle organoid, most from rodents or small animals, and only recently some studies have been reported on the muscles of large animals. This work presents a muscular organoid produced from the bovine diaphragm, which has a peculiar multilayered structure with different fibre orientations depending on the considered area. This paper analyses the anatomical structure of the bovine diaphragm, selects the most appropriate portion, and presents a decellularization protocol for a multilayered muscle. In addition, a preliminary test of recellularization with primary bovine myocytes was presented with the future aim of obtaining a 3D muscle allogenic organoid, completely bovine-derived. The results demonstrate that the dorsal portion of bovine diaphragm presents a regular alternation of muscular and fibrous layers and that the complete decellularization does not affect the biocompatibility. These results provide a strong foundation for the potential application of this portion of tissue as a scaffold for in vitro studies of muscle organoids.

INGREDIENTS DEGRADATION IN STEEL FIBER REINFORCED CONCRETE AFTER THERMAL LOADING

The steel fiber reinforced concrete in structures provides good mechanical and physical characteristics and such material applications are increasing. At the same time, if structure is subjected to thermal load it is affecting both properties of reinforcement and matrix as well. The aim of the present research is to investigate the degradation of the characteristics of fibers, randomly distributed in the body of concrete block. A short steel fiber reinforced concrete slabs (400x300x18cm) [1], [2] with homogeneously distributed fibers was undergone to calefaction process from one side. dimension of 16.5x14.5x15 cm) Fiber fracture process was performed based on the single fiber pull-out test by preparing the specimens with fiber from calefacted SFRC block. Experimental curves from each layer were compared with different layer of fibers and investigation had shown that higher load-bearing capacity is there over the thermal loaded fiber. The conclusion were made with the microscopic results and the experimental data.

The continuous structure of the joint capsule and meniscus in the pig knee.

The knee joint capsules composed of a fibrous layer and a synovial layer. The knee meniscus consists of the superficial network, lamellar layer, tie fibre and circumferential bundles. However, the continuous structure of the knee joint capsule and meniscus has not been reported. Fetal and adult pigs were used to investigate the structural relationship between the stifle joint capsule and meniscus based on the gross anatomy and histological findings. In the gross anatomical examination, the joint capsule appeared to have separated attachments to the meniscus, except for the lower aspect of the popliteal hiatus. Histologically, the lower half of the popliteal hiatus was found to have separated attachments, with vessels running between the attachments of the joint capsules. The synovial layer of the joint capsule continued to the superficial network, and the fibrous layer of the joint capsule continued to the lamellar layer and tie fibres. There were two routes of arterial entry into the meniscus: intracapsular and intercapsular. It appeared that the presence of separated attachments of the joint capsule was necessary to allow the intercapsular route. This study clarified for the first time the routes of feeding vessels entering the meniscus and proposed to call this entry point the meniscus hilum. We consider that this detailed anatomical information is important for understanding the continuation between the joint capsule and the meniscus.

The Applicability of Machine Learning Methods to the Characterization of Fibrous Gas Diffusion Layers

Porous materials can be characterized by well-trained neural networks. In this study, fibrous paper-type gas diffusion layers were trained with artificial data created by a stochastic geometry model. The features of the data were calculated by means of transport simulations using the Lattice–Boltzmann method based on stochastic micro-structures. A convolutional neural network was developed that can predict the permeability and tortuosity of the material, through-plane and in-plane. The characteristics of real data, both uncompressed and compressed, were predicted. The data were represented by reconstructed images of different sizes and image resolutions. Image artifacts are also a source of potential errors in the prediction. The Kozeny–Carman trend was used to evaluate the prediction of permeability and tortuosity of compressed real data. Using this method, it was possible to decide if the predictions on compressed data were appropriate.

Novel oviduct endoscope combining optical coherence tomography with intratubal ultrasonography for fallopian tube exploration: An in vivo rabbit pilot study

Background and study aimCurrently, several limitations exist in the examination of the oviduct. In this study, the usefulness and feasibility of a novel ultrafine dual-modality oviduct endoscopy device for in vivo assessment of the oviduct were evaluated. MethodsFive Japanese white rabbits were selected to undergo oviduct probing using a combination of optical coherence tomography (OCT) and intratubal ultrasonography. The feasibility of the procedure was evaluated through 152 pairs of clear, clinically interpretable images obtained using spiral scanning via the pull-back method. OCT images were compared with the oviduct histopathology sections. ResultsVisualization of the oviduct using both OCT and ultrasound revealed a differentiated three-layer tissue; however, ultrasound showed a poorer clarity than OCT. By comparing OCT images with the histological morphology of the oviduct, the inner low-reflective layer of the oviduct corresponds to the mucosal layer, the middle high-reflective layer corresponds to the fibrous muscle layer, and the outer low-reflective layer corresponds to the connective tissue layer. Postoperatively, the general condition of the animals was good. ConclusionThis study demonstrated the feasibility and potential clinical value of the novel ultrafine dual-modality oviduct endoscope. Dual-modality imaging of OCT and intratubal ultrasonography can provide clearer microstructure of the oviduct wall.

PENGARUH SUDUT PAHAT PADA PENGGURDIAN KOMPOSIT SERAT DAUN NANAS / TERMOPLASTIK PADA PEMBENTUKAN DELAMINASI

This study aims to determine the effect of the Gurdi tool angle on delamination in composite laminates in the formation of delaminations. The spacing of the selected reinforcing fibers was 2.4 and 6 mm in a composite laminate of ethylene vinyl acetate (EVA) polymer matrix with reinforcing fibers from pineapple leaves. The method used in composite fabrication is hand lay-up, namely by direct casting on three layers of fiber that has been woven and tied to the sides of the mold. For cutting speed, Vf 72 mm / min, using a chisel with a diameter of 8 mm with a tool angle of 70o and 118o. Delamination was determined using the Feda method. The delamination sections were observed using a digital microscope and then processed using AutoCAD to measure Dmax and Ad. The delamination ratio in the top hole for the tool diameter of 8mm with a 70° angle at the variation of the distance of 2 mm, 4 mm and 6 mm were 1.268, 1.224 and 1.192 for the bottom hole were 1.078, 1.042 and 1.029, respectively. Meanwhile, the ratio of delamination in the upper hole for a tool diameter of 8mm with an angle of 118° at a distance variation of 2mm, 4mm and 6mm were 1.194, 1.194, 1.158 for the bottom hole, respectively, 1.046, 1.042 and 1.038.

Energy absorption and deformation modes of several thin-walled tubes under dynamic compression

Thin-walled tubes have shown extraordinary advantages in terms of light weight and energy absorbing impact scenarios. Based on hexagonal, re-entrant and square honeycombs, several new honeycomb thin-walled tubes were designed by reducing the wall thickness and increasing the number of webs with consistent quality. Low-velocity compression experiment and high-velocity impact finite element simulation were conducted on the honeycomb thin-walled tubes to study the effect of porous type on energy absorption and deformation behavior. Finite element model was established, and the finite element simulation results were verified with the experimental results. By comparing the thin-walled tubes with different porous types, the results show that the H0 has better energy absorption. The energy absorption of the re-entrant thin-walled tube is enhanced by adding web, and the RC has 38% higher energy absorption than the R0. The deformation modes of each structure were discussed and it was found that the thin-walled tubes of PLA material generally cracked at the fiber layer.

High-speed impact performance of a high-performance concrete with functionally gradient structure designs

Ultra-high performance concrete is characterized by its high strength and high toughness, and ceramsite concrete can absorb energy and function as a buffer. Based on the mechanical properties of both, the two kinds of concrete materials are combined in the spatial structure, and three structural models, namely, gradient structure group target, double stacked structure group target, and single material structure group target, are designed and prepared. Then, the dynamic characteristics and protection performance of the three targets are compared and analyzed via experiments and numerical simulations under different projectile penetration velocities. The results show that because the two transition layers and the fiber layer between the interfaces are set in the gradient structure group target, which largely improves the resistance in the process of projectile penetration, the cratering area, cratering depth, and penetration depth of the gradient structure group target are the smallest under the same projectile penetration velocity. The larger the projectile penetration velocity is, the more outstanding the penetration resistance of the gradient structure group target is.

Neutron Imaging Experiments to Study Mass Transport in Commercial Titanium Felt Porous Transport Layers

In this work, neutron imaging was used to visualize and study invasion phenomena in fibrous porous transport layers (PTLs) of titanium felt under different flow conditions of gas and liquid phase. The experiments were realized with flow cells that contained a gas and a liquid flow channel separated by PTLs with different thicknesses and pore size distributions. The invasion can be characterized by counter-current flow of water and air with joint imbibition and drainage processes. The dynamics were visualized with neutron radiography with a local resolution of 6.5 μm and a temporal resolution of 0.1 s. Individual static gas-liquid distributions were additionally studied by neutron tomography, with a local resolution of 22 μm and an exposure time of 1.5 s per image (projections: 800/360°). It is shown and discussed that the invasion occurred in continuously repeated imbibition/drainage cycles with frequencies depending on the flow conditions and the PTL structure as well. The change of the PTL saturation with air or water appeared almost independent from the specific PTL structure and the breakthrough of the gas phase occurred at almost constant positions.

Characterization of the rat pituitary capsule: Evidence that the cerebrospinal fluid filled the pituitary cleft and the inner side of the capsule.

In humans, the pituitary gland is covered by a fibrous capsule and is considered a continuation of the meningeal sheath. However, in rodents some studies concluded that only the pars tuberalis (PT) and pars nervosa (PN) are enwrapped by the pia mater, while others showed that the whole gland is covered by this sheath. At PT the median eminence subarachnoid drains cerebrospinal fluid (CSF) to its cisternal system representing a pathway to the hypothalamus. In the present study we examined the rat pituitary capsule to elucidate its configuration, its physical interaction with the pituitary border and its relationship with the CSF. Furthermore, we also revisited the histology of the pituitary cleft and looked whether CSF drained in it. To answer such questions, we used scanning and transmission electron microscopy, intracerebroventricular infusion of Evan´s blue, fluorescent beads, and sodium fluorescein. The latter was measured in the pars distalis (PD) and various intracranial tissues. We found a pituitary capsule resembling leptomeninges, thick at the dorsal side of the pars intermedia (PI) and PD, thicker at the level of PI in contiguity with the PN and thinner at the rostro-ventral side as a thin membrane of fibroblast-like cells embedded in a fibrous layer. The capsule has abundant capillaries on all sides. Our results showed that the CSFs bathe between the capsule and the surface of the whole gland, and ciliate cells are present in the pituitary border. Our data suggest that the pituitary gland intercommunicates with the central nervous system (CNS) through the CSF.

(112) An Experimental Animal Study of the Histopathological Effect of Collagen Fleece (TachoSil) Patch of Tunica Albuginea Defects Associated with Penile Surgery

Abstract Introduction A penile tunica defect may arise during penile prosthesis surgery or reconstruction of the penis in patients with Peyronie’s disease. Collagen fleece (TachoSil) was recently reported in penile surgery to cover the tunica defect with reported clinical success. However, it is not known what the histological outcomes of these grafts are in the penis. Objective We study the novel application of TachoSil graft in an experimental animal model. We looked at the regeneration of tunica albuginea, development of inflammation and fibrosis, and histopathological effect on the underlying cavernous tissue. Methods Seven adult male Sprague Dawley rats were used. All procedures were carried out under general inhalation anesthesia. The penis was degloved through a circumferential subcoronal incision. A longitudinal 1x10 mm defect was created at the base of the lateral aspect of the penis. A TachoSil patch (Takeda, Japan) was applied to the defect in six rats and Surgicel (Ethicon) in one. The penile skin covering is then restored and fixed with interrupted 5-6 zero absorbable sutures. At two months, the rat penis was evaluated for excision. Euthanasia was carried out with an overdose of inhalation anesthesia and chest opening. The excised penis was examined by hematoxylin and eosin and trichrome stains. Results At the time of surgery, the rats’ weight was 390 gm (SD 33.8). All rats with TachoSil showed normal-looking penis at two months with complete healing, no scaring, tethering, or gross inflammatory features. The penis of three rats with a Tachosil patch was harvested at two months postoperatively. It showed histopathology of fibrosis, chronic inflammation, and foreign body giant cell reaction at the site of the patch. There was no generation of a new tunica albuginea, no new vascularity or distinct fibrous layer development. The underlying corpus cavernous tissue was not affected by any inflammatory or pathological reaction. One rat died on the 6th postoperative day. Postmortem showed massive gastrointestinal bleeding, intraperitoneal hemorrhage, and punctate hemorrhages of the parenchyma of both suprarenal glands, both kidneys, and the liver. A clinical diagnosis of DIC was made. Histopathology of the penis, however, did not show micro thrombosis. The fifth rat with a Surgicel patch showed immediate hematoma of the penis controlled by compression. After two months, during harvesting of the penis, large pockets of pus were seen spreading from the site of the patch to surrounding structures. Histopathology showed chronic inflammation and fibrosis extending into the corpus cavernosum. The sixth and seventh rats showed normal penis external appearance at two months and were left surviving for harvest at four months. Conclusions Tachosil patching of penile tunica albuginea defect forms a distinctive barrier against inflammation protecting the underlying corpus cavernosum. However, no regeneration of tunica defect is observed at two months. DIC is a potential complication of systemic absorption of TachoSil. Disclosure No

Characteristics of Henle's fiber layer in healthy and glaucoma eyes assessed by polarization-sensitive optical coherence tomography.

Using conventional optical coherence tomography (OCT), it is difficult to image Henle fibers (HF) due to their low backscattering potential. However, fibrous structures exhibit form birefringence, which can be exploited to visualize the presence of HF by polarization-sensitive (PS) OCT. We found a slight asymmetry in the retardation pattern of HF in the fovea region that can be associated with the asymmetric decrease of cone density with eccentricity from the fovea. We introduce a new measure based on a PS-OCT assessment of optic axis orientation to estimate the presence of HF at various eccentricities from the fovea in a large cohort of 150 healthy subjects. By comparing a healthy age-matched sub-group (N = 87) to a cohort of 64 early-stage glaucoma patients, we found no significant difference in HF extension but a slightly decreased retardation at about 2° to 7.5° eccentricity from the fovea in the glaucoma patients. This potentially indicates that glaucoma affects this neuronal tissue at an early state.