Total Number Of Fibers Research Articles

Design and In Vivo Testing of an Anatomic 3D-Printed Peripheral Nerve Conduit in a Rat Sciatic Nerve Model.

Background: Three-dimensional (3D) printer technology has seen a surge in use in medicine, particularly in orthopedics. A recent area of research is its use in peripheral nerve repair, which often requires a graft or conduit to bridge segmental defects. Currently, nerve gaps are bridged using autografts, allografts, or synthetic conduits. Purpose: We sought to improve upon the current design of simple hollow, cylindrical conduits that often result in poor nerve regeneration. Previous attempts were made at reducing axonal dispersion with the use of multichanneled conduits. To our knowledge, none has attempted to mimic and test the anatomical topography of the nerve. Methods: Using serial histology sections, 3D reconstruction software, and computer-aided design, a scaffold was created based on the fascicular topography of a rat sciatic nerve. A 3D printer produced both cylindrical conduits and topography-based scaffolds. These were implanted in 12 Lewis rats: 6 rats with the topographical scaffold and 6 rats with the cylindrical conduit. Each rodent's uninjured contralateral limb was used as a control for comparison of functional and histologic outcomes. Walking track analysis was performed, and the Sciatic Functional Index (SFI) was calculated with the Image J software. After 6 weeks, rats were sacrificed and analyses performed on the regenerated nerve tissue. Primary outcomes measured included nerve (fiber) density, nerve fiber width, total number of nerve fibers, G-ratio (ratio of axon width to total fiber width), and percent debris. Secondary outcomes measured included electrophysiology studies of electromyography (EMG) latency and EMG amplitude and isometric force output by the gastrocnemius and tibialis anterior. Results: There were no differences observed between the cylindrical conduit and topographical scaffold in terms of histological outcomes, muscle force, EMG, or SFI. Conclusion: This study of regeneration of the sciatic nerve in a rat model suggests the feasibility of 3D-printed topographical scaffolds. More research is required to quantify the functional outcomes of this technology for peripheral nerve regeneration.

Parallel Analogy Method for Measuring FRD of the FASOT-IFU

A fiber integral field unit (IFU) was chosen for the Fiber Array Solar Optical Telescope (FASOT) to obtain high-spectral-resolution polarization solar spectral images. This IFU features a dual-array-end design, complemented by a dozen slit ends. Each consists of 2 sub-slits corresponding to the dual array ends. In order to accurately and quickly measure the focal ratio degradation of 8064 fibers in FASOT-IFU, a parallel analogy method (PAM) for FASOT-IFU was proposed. This method primarily relies on characterizing the focal ratio based on the full-width at half-maximum (FWHM) of the fiber’s output spot, and the linear relationship between the output focal ratio of the spot and the FWHM. By precisely calculating the focal ratio of the positioning fiber in the FASOT-IFU and treating it as a reference, the output focal ratio of the working fiber can be obtained by comparing the FWHM of the working fiber spot and the positioning fiber spot at the same emission distance. The average value of the output focal ratio by PAM corresponding to the 4032 fibers from Array A of the IFU is 6.0 and the standard deviation is 0.6. The values corresponding to the Array B are 6.2 and 0.40, respectively. The mean value exceeds the contractually specified F/5.5, and the proportion of optical fibers with a focal ratio greater than 5.5 accounts for 88% of the total number of optical fibers, meeting the design requirements of the FASOT system.

Precise quantification of skeletal muscle fibers reveals the physiological basis for growth rate discrepancies in broilers1

Skeletal muscle is composed of multinucleated muscle fibers, which play a crucial role in determining the quality of meat products in livestock. Quantifying the total number of muscle fibers (TNM) is essential for understanding muscle composition, yet remains challenging in poultry, particularly due to the size of the livestock that complicates the preparation of tissue sections for analysis and renders the counting process laborious. Our previous study developed an automatic muscle fiber quantification tool powered by deep learning, named MyoV, which has addressed this bottleneck. This study aimed to employ the tool for the accurate quantification of the TNM in the pectoral muscles of slow-growing (SL), medium-growing (ML), and fast-growing (FL) broilers. Results showed that FL exhibited higher growth performance compared to ML and SL from embryonic to rearing stages. Processing of whole slide images of pectoral muscle revealed significantly higher TNM in FL and ML than in SL (P < 0.01). The TNM of FL, ML and SL were 693,568.00 ± 54,169.80, 652,122.00 ± 65,822.60 and 539,778.57±40,722.94 at 7 days of age (D7), respectively. And the TNM at D35 were 663,014.93±58,801.11, 645,784.76±80,204.34 and 507,280.29±98,092.16 of FL, ML and SL. Differences in cross-sectional area (CSA) of muscle fibers among the three groups were consistent with TNM results. Correlation analysis showed a correlation coefficient of 0.73-0.89 between body weight (BW) and TNM and a correlation coefficient of 0.78-0.87 between BW and CSA. These findings directly indicate that the number of muscle fibers in broilers is an important foundation for their rapid growth and development. This study precisely quantifies the muscle fiber number of important skeletal muscle in poultry for the first time, providing the direct evidence for the physiological basis of rapid development in broilers and offering important data support for further in-depth researches on muscle fiber development.

Differential Acute Adipogenic Signaling Changes Following Neuromusculoskeletal Injuries

Following traumatic injury, neuromusculoskeletal tissue undergoes extensive plastic modification. Changes can be observed at the local and systemic levels and can involve tissue function, signaling, and local composition. Currently there is limited understanding of early adipogenic changes following some traumatic injuries, which is needed to understand the long-term lack of functional muscle recovery. The objective of this project was to examine plasticity after injury, namely systemic and local adipogenic signaling and fat droplet deposition following volumetric muscle loss (VML) and denervation injuries. We hypothesized there would be differential changes in local and systemic adipogenic signaling, specifically changes in fat droplet accumulation following neuromusculoskeletal injuries. Adult C57B1/6J mice (n=36; 6 male, 6 female/group): posterior compartment VML, tibial nerve denervation, and naïve control. Both injury models target plantarflexor muscles. Mice were euthanized 72-hrs post-injury. In vivo muscle function was assessed, and gastrocnemius, liver, and serum were saved for analysis. Whole gastrocnemius muscles from a subset (n=4/group) were saved for histology, and five standardized sections were systematically obtained 1.5mm apart; muscle sections were stained with H&amp;E and Oil-Red-O to evaluate total fiber number and fat droplet accumulation, respectively. Data were analyzed by two- and three-way ANOVA with Tukey’s HSD post hoc. Maximal torque declined ~81 and 98% following VML and denervation injury, respectively (main effect p&lt;0.001), and VML-injured muscle was more fatigable than injury naïve (main effect p=0.001). Following denervation, liver insulin-like growth factor 1 (IGF-1) was increased ~52% compared to other groups, and was most pronounced in males (main effect injury p&lt;0.001; sex p=0.021). VML injury resulted in a 4-fold higher muscle IGF-1 regardless of sex (interaction p=0.021), and greater muscle interleukin-6 (IL-6), which was more pronounced in females (main effect injury p=0.001; sex p=0.049). Platelet-derived factor growth receptor (PDFGRα) expression was diminished following VML injury in both sexes (interaction p=0.016); suggesting a decrease in fibro-adipogenic progenitors (FAPs) and an alternative origin responsible for increases in IGF-1 and IL-6 rather than FAPs. Serum leptin concentrations were blunted following both VML- and denervation-injury (main effect p=0.002), which may illicit alterations in the regenerative process, specifically the maintenance of muscle quality. Serum IGF-1 and IL-6 concentrations were not affected by injury (p≥0.164). Histological analysis revealed a significant decrease in total fiber number across the middle three sections of the VML-injured muscle (i.e., the section initially injured) compared to other groups (p≤0.034). Findings provide a foundation for characterizing adipocyte development in the muscle remaining after injury and identify therapeutic targets for rehabilitative and nutritional approaches to address contractile and metabolic impairments following injury. Future work should elucidate the time course of adipogenic signaling following these injuries, with particular interest in their relationship to changes in metabolic and contractile impairments. R01-AR078903 (JAC &amp; SMG); University of Minnesota UROP (BAC). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Classification of South American Camelid and goat fiber samples based on fourier transform infrared spectroscopy and machine learning

Some animal fibers are considerably cheaper than others. Hence the existence of counterfeit products, which are detrimental to legitimate producers and consumers alike. Fourier-Transform Infrared (FTIR) spectroscopy can extract a characteristic waveform from fibers that can be later used for classification. However, visually inspecting such waveforms is imprecise. Previous research has complemented FTIR with other mathematical or physical methods to improve accuracy. In parallel, Artificial Intelligence (AI) is an emerging field that could be helpful in this domain. The objective of this work is therefore to develop and validate two machine learning models, namely, Deep Neural Networks (DNN) and Support Vector Machine (SVM) to classify spectra of fibers by species. The spectra are acquired using an FTIR spectrometer in Attenuated Total Reflectance (ATR) mode (FTIR-ATR). Camelid (alpaca: n = 51, llama: n = 50, vicuña: n = 50) and goat (mohair: n = 35 and cashmere: n = 20) samples were evaluated, from which 1236 FTIR-ATR spectra were obtained. Some visual differences were observed between the spectra of the different species. Accuracies up to 96.75% and 95.12% were obtained when evaluating the DNN and SVM models. Furthermore, an accuracy of 97.8% was obtained when evaluating the FTIR-ATR spectra of South American Camelids (SAC) fibers with DNN, and 97.2% when evaluating them with SVM. A 100% accuracy was obtained when evaluating the FTIR-ATR spectra of vicuña fibers with both models. No significant differences were found (p-value = 0.368) by comparing the number of hits against the total number of alpaca, llama, vicuña, mohair and cashmere fibers using DNN. As per the results, it seems that DNN is more accurate than SVM. In conclusion, FTIR-ATR spectrometry techniques combined with machine learning models are a reliable alternative for the identification of SAC and goats through the spectrum of their fibers.

Emergence of Dynamic Instability by Hybridizing Synthetic Self-Assembled Dipeptide Fibers with Surfactant Micelles.

Supramolecular chemistry currently faces the challenge of controlling nonequilibrium dynamics such as the dynamic instability of microtubules. In this study, we explored the emergence of dynamic instability through the hybridization of peptide-type supramolecular nanofibers with surfactant micelles. Using real-time confocal imaging, we discovered that the addition of micelles to nanofibers induced the simultaneous but asynchronous growth and shrinkage of nanofibers during which the total number of fibers decreased monotonically. This dynamic phenomenon unexpectedly persisted for 6 days and was driven not by chemical reactions but by noncovalent supramolecular interactions between peptide-type nanofibers and surfactant micelles. This study demonstrates a strategy for inducing autonomous supramolecular dynamics, which will open up possibilities for developing soft materials applicable to biomedicine and soft robotics.

The Effect of Birth Weight on Fattening Performance, Meat Quality, and Muscle Fibre Characteristics in Lambs of the Karayaka Native Breed.

This investigation aimed to assess the influence of birth weight on post-weaning fattening performance, meat quality, muscle fibre characteristics, and carcass traits in Karayaka lambs. The study categorized the lambs into three distinct groups based on birth weight: low birth weight (LBW), medium birth weight (MBW), and high birth weight (HBW). Throughout the fattening phase, the lambs were given ad libitum access to food and water, culminating in the slaughter at the end of the study. Following slaughter, warm and cold carcasses were weighted, and specific muscles (longissimus thoracis et lumborum [LTL], semitendinosus [ST], and semimembranosus [SM]) were isolated for the evaluation of muscle weights, muscle fibre types (Type I, Type IIA, and Type IIB), and muscle fibre numbers. Carcass characteristics were also determined, including eye muscle (LTL) fat, loin thickness, and meat quality characteristics, such as pH, colour, texture, cooking loss, and water-holding capacity. The statistical analysis revealed highly significant differences among the experimental groups concerning muscle weights and warm and cold carcass weights (p < 0.01), with the lambs in the HBW group exhibiting a notably higher carcass yield (in females: 45.65 ± 1.34% and in males: 46.18 ± 0.77%) and LTL, ST, and SM (except for female lambs) muscle weights than the lambs in LBW group (p < 0.01). However, apart from the texture of LTL and ST muscles, no significant differences in meat quality parameters were observed among the treatment groups (p > 0.05). Notably, the birth weight of lambs did not impart a discernible effect on the total number and metabolic activity of muscle fibres in LTL, ST, and SM muscles. Nonetheless, a noteworthy distinction in the fibre area of Type I fibres in the LTL muscle of male lambs (LBW: 30.4 ± 8.9, MBW: 29.1 ± 7.3 and HBW; 77.3 ± 15.4) and in the ST muscle of female lambs (LBW: 44.1 ± 8.1, MBW: 38.8 ± 7.7 and HBW: 36.9 ± 7.1) were evident among the birth weight groups (p < 0.05). The study also found that the mean fat thickness values of eye muscles in Karayaka lambs, as obtained by ultrasonic tests, were below the typical range for sheep. In synthesis, the outcomes of this study underscore the considerable impact of birth weight on slaughtered and carcass weights, emphasizing the positive association between higher birth weights and enhanced carcass yield. Remarkably, despite these pronounced effects on carcass traits, the birth weight did not demonstrate a statistically significant influence on meat quality or overall muscle fibre characteristics, except for the area of Type I fibres in the LTL muscle. This nuanced understanding contributes valuable insights into the intricate relationship between birth weight and various physiological and carcass parameters in Karayaka lambs undergoing post-weaning fattening.

Dietary creatine promotes creatine reserves, protein deposition, and myofiber hyperplasia in muscle of juvenile largemouth bass (Micropterus salmoides)

Creatine can increase muscle mass, enhance performance, prevent disease-induced muscle atrophy, and improve overall cellular energy. This study investigated the effects of creatine as a feed additive on muscle growth and intrinsic molecular regulation mechanism in largemouth bass (Micropterus salmoides). Seven diets supplemented with different concentrations of creatine (0%, 0.1%, 0.25%, 0.5%, 1%, 2%, and 4%) were fed to juvenile largemouth bass (4.5–5.1 g) for eight weeks. Dietary creatine significantly increased body weight and body length, and reduced feed conversion ratio. High-performance liquid chromatography analysis revealed that dietary creatine addition notably increased creatine and phosphocreatine levels by 19.94% and 16.54% in the muscle of largemouth bass, respectively. Histological observation showed that dietary creatine significantly increased the total muscle fiber number and decreased the mean muscle fiber diameter. The Western blot results indicated that creatine ingestion significantly increased the protein level of MyoD1 in the muscle and promoted muscle fiber hyperplasia. In addition, dietary creatine also contributed to mTOR-S6K/4EBP1-mediated protein synthesis by maintaining AMPKα Thr172 dephosphorylation and AKT Thr308 phosphorylation. Moreover, the protein levels of the muscle-specific E3 ligases Atrogin1 and Murf1 responsible for ubiquitination degradation exhibited no significant change after feeding with creatine in largemouth bass. Overall, our data showed that creatine as a feed additive increased creatine and phosphocreatine contents, thus promoting muscle protein deposition and myofiber hyperplasia, eventually elevating growth performance and feed utilization efficiency in juvenile largemouth bass. The regression analysis of weight gain rate, specific growth rate, and feed conversion ratio determined 0.46%–0.54% creatine concentration range as optimal supplementation concentration for the culture of juvenile largemouth bass.

Expression of calcitonin gene-related peptide in atopic dermatitis and correlation with distress

Background Atopic dermatitis (AD) is a chronic, inflammatory, often severely itching skin disorder. It may worsen due to stress, depression, or anxiety. Calcitonin gene-related peptide (CGRP) may be involved in inflammation signaling. CGRP has also been suggested in relation to stress, depression, and anxiety. This study aimed to investigate the expression of CGRP in the skin of patients with AD. Methods Twenty-seven adult patients with AD, characterized with clinical and psychodemographic parameters, were investigated regarding CGRP expression in skin biopsies, using an immunohistochemical technique. Results The total number of CGRP-positive nerve-like fibers was found to be higher in lesional skin than in non-lesional skin. Moreover, more inflammatory cells of dendritic shape intruded into the epidermis in lesional skin compared to non-lesional skin. Keratinocytes showing expression of CGRP were also found in lesional skin. Interestingly, the number of CGRP-positive nerve-like fibers in lesional skin correlated with depressive and anxiety scores. Correlation with depressive score was also found for round CGRP-positive inflammatory cells in the epidermis. Conclusions CGRP may have a role in both the inflammatory process and distress, in AD.

Skeletal muscle wasting after burn is regulated by a decrease in anabolic signaling in the early flow phase

Following burns a sustained catabolic stress response is activated, resulting in skeletal muscle wasting. A better understanding of the underlying mechanisms of postburn skeletal muscle wasting is essential for the development of preventive and/or therapeutic strategies. Six weeks old female rats underwent a sham, 10% or 40% total body surface area scald burn. Ten days post-injury, severely burned animals gained significantly less weight compared to sham treated and minor burned animals, reflected in a significantly lower ratio of muscle to total body weight for Soleus (SOL) and Extensor Digitorum Longus (EDL) in the severely burned group. Postburn, total fiber number was significantly lower in EDL, while in SOL the amount of type1 fibers significantly increased and type2 fibers significantly decreased. No signs of mitochondrial dysfunction (COX/SDH) or apoptosis (caspase-3) were found. In SOL and EDL, eEF2 and pAKT expression was significantly lower after severe burn. MURF1,2,3 and Atrogin-1 was significantly higher in SOL, whilst in EDL MURF1,2,3 was significantly lower postburn. In both muscles, FOXO3A was significantly lower postburn. This study identified postburn changes in muscle anthropomorphology and proteins involved in pathways regulating protein synthesis and breakdown, with more pronounced catabolic effects in SOL.

Muscle fiber characteristics and expression level of Troponin T3, Toll-like receptor 2, and Toll-like receptor 4 genes in chicken meat with white striping.

The poultry industry faces an emerging muscular defect in chicken meat called white striping (WS). The biological processes associated with WS myopathy are immune system activation, angiogenesis, hypoxia, cell death, and striated muscle contraction. We examined the Troponin T3 (TNNT3), Toll-like receptor 2 (TLR2), and Toll-like receptor 4 (TLR4) genes based on their functions related to muscle contraction and the innate immune system. This study aimed to determine the muscle fiber characteristics (MFCs) and expression level of TNNT3, TLR2, and TLR4 genes in white striping chicken meat (WSCM). A total of 428 breast samples were randomly collected from a commercial poultry processing plant. The samples were classified into four levels: 0 (normal), 1 (moderate WS), 2 (severe WS), and 3 (extreme WS). Five samples per group were selected to evaluate MFCs, including total number of muscle fibers, muscle fiber diameter, cross-sectional area, endomysium thickness, and perimysium thickness. Five samples per group were selected for ribonucleic acid (RNA) isolation to evaluate the messenger RNA (mRNA) expression levels of TNNT3, TLR2, and TLR4 genes related to WS. Statistical analysis revealed that the total number of fibers, endomysium thickness, and perimysium thickness significantly differed between groups (p < 0.05). Muscle fiber diameter and cross-sectional area did not significantly differ (p > 0.05). The expression of the TNNT3 gene did not significantly differ among groups (p > 0.05). Toll-like receptor 2 and TLR4 mRNA expression significantly differed among groups (p < 0.05). These detailed MFCs will provide baseline information to observe WS in chicken meat. Toll-like receptor 2 and TLR4 genes may play a role in the occurrence of WS in chicken meat through non-specific immune reactions.

(001) How many Nerve Fibers Innervate the Human Clitoris? A Histomorphometric Evaluation of the Dorsal Nerve of the Clitoris

Abstract Introduction It is frequently quoted in mainstream media that the clitoris has “8000 nerve endings”. However, no study has yet quantified the number of nerve fibers (axons) innervating the human clitoris. The dorsal nerve of the clitoris (DNC) is the primary source of somatic clitoral innervation. Reporting the number of axons in the DNC is an important step in our understanding of clitoral innervation and sexual response with implications for many fields of medical practice. Reconstruction following iatrogenic injuries to the dorsal clitoral nerve and restoration following cases of genital mutilation will benefit from a better understanding of the DNC. This knowledge will also be an important factor contributing to the optimization of nerve selection and sensory outcomes in gender-affirming genital surgery. Objective The purpose of this study is to quantify the number of nerve fibers in the human dorsal nerve of the clitoris (DNC) and report the approximate number of nerve fibers that innervate the human clitoris. Methods Following institutional approval and informed consent, dorsal clitoral nerve samples were obtained from 7 transmasculine patients undergoing gender-affirming phalloplasty surgery. In phalloplasty one of the two dorsal clitoral nerves is used to coapt to a sensory nerve in the phallus in order to provide for erogenous phallic sensation. At the time of nerve coaptation, a small excess of dorsal clitoral nerve (5 mm) was collected for analysis at the proximal level of the clitoral body, just after appearance of the dorsal clitoral nerve from underneath the pubic symphysis. The samples were placed into 3% glutaraldehyde fixative, post-fixed in 1% osmium tetroxide and serially dehydrate in ethanol and toluene. They were then embedded in araldite, sectioned on ultramicrotome into 1 μm cross sections and counter-stained with 1% toluidine blue. Histomorphometric evaluation was performed at 1000x magnification using a Leitz Laborlux S microscope and image analysis software (Clemex Vision Professional, Longueuil, Quebec) in order to obtain a nerve fiber count from each dorsal clitoral nerve specimen. Descriptive statistics were performed to yield a mean and range of the number of nerve fibers in the DNC. Assuming anatomic symmetry between bilateral DNC, the total number of somatic nerve fibers innervating the human clitoris was obtained by doubling the mean count of the DNC. Results 7 samples of the DNC were collected. The mean number of nerve fibers in the human dorsal clitoral nerve was 5140 with a range of 4926 to 5543. The mean number of myelinated nerve fibers innervating the human clitoris was 10281 (range 9852 to 11086). Conclusions This study is the first to report the number of myelinated nerve fibers in the human dorsal clitoral nerve and approximate the number of nerve fibers innervating the human clitoris. Findings demonstrate high and consistent myelinated axon counts and density. When taking into account the presence of uncounted unmyelinated axons, it is clear that far more than 8000 fibers innervate the human clitoris. Disclosure No

How many nerve fibers innervate the human glans clitoris: a histomorphometric evaluation of the dorsal nerve of the clitoris.

It is frequently quoted in mainstream media that the clitoris has "8000 nerve endings." However, no study has yet quantified the number of nerve fibers (axons) innervating the human clitoris. The dorsal nerves of the clitoris (DNCs) are the primary source of sensation and somatic clitoral innervation. Therefore, reporting the number of axons in the DNCs is an important step in our understanding of clitoral innervation and sexual response with implications for many fields of medical practice. The purpose of this study is to quantify the mean number of axons in the human DNCs and to report the approximate mean number of nerve fibers that innervate the human glans clitoris. DNC samples were obtained from 7 transmasculine patients undergoing gender-affirming phalloplasty surgery. At the time of nerve coaptation, a small excess of the DNC (5 mm) was collected for analysis at the proximal level of the clitoral body, just distal of the emergence of the DNCs from underneath the pubic symphysis. Samples were placed into 3% glutaraldehyde fixative, postfixed in 1% osmium tetroxide, and serially dehydrated in ethanol and toluene. Samples were then embedded in araldite, sectioned on an ultramicrotome into 1-μm cross sections, and counterstained with 1% toluidine blue. Histomorphometric evaluation was performed at 1000x magnification with a Leitz Laborlux S microscope and image analysis software (Clemex Vision Professional) to obtain an axon counts. Descriptive statistics were performed to yield a mean and standard deviation of the number of axons in the DNCs. Assuming anatomic symmetry between bilateral DNCs, mean total number of somatic nerve fibers innervating the human glans clitoris was obtained by doubling the mean count of the DNCs. Seven sample DNCs were collected. Of those, 5 were analyzed as 2 did not have sufficient nerve tissue present. The mean number of nerve fibers in the human DNCs was 5140 (SD = 218.4). The mean number of myelinated nerve fibers innervating the human clitoris was 10,281 (SD = 436.8). This study is the first to report the number of axons in the human DNC, at a mean 5140. Given the bilateral nature of clitoral innervation and symmetry of anatomic structures, the approximate mean number of myelinated axons that innervate the human glans clitoris is 10,280. When the uncaptured unmyelinated fibers and contributions from the cavernosal innervation are accounted for, it is clear that far Moree than 8000 axons innervate the human clitoris.

The different damage patterns of short-, middle- and long-range connections between patients with relapse-remitting multiple sclerosis and neuromyelitis optica spectrum disorder.

To investigate the differences in short-, middle- and long-range connections between patients with relapse-remitting multiple sclerosis (RRMS) and neuromyelitis optica spectrum disorder (NMOSD), and their correlation with brain tissue volume, structural and functional network parameters. A total of 51 RRMS, 42 NMOSD and 56 health controls (HC) were recruited. Of these 25 RRMS (median: 1.37 years) and 20 NMOSD (median: 1.25 years) patients were also studied at follow-up. The whole-brain fiber connection was divided into three groups according to the trisected lengths of the tract in HC group, including short-, middle- and long-range connections. The brain tissue features (including total brain tissue and deep grey matter volumes) and parameters of DTI and functional networks (including the shortest path, clustering coefficient, local efficiency and global efficiency) were calculated. The differences in fiber number (FN) and average fractional anisotropy (FA) were compared between RRMS and NMOSD by the One-way ANOVA and post hoc tests. The correlation between the FN or FA and the brain tissue volume, DTI and functional network parameters were further analyzed by Pearson analysis. Compared to HC and NMOSD, the total number of fibers in RRMS was decreased, including the reduced FN of middle- and long-range connections, but increased FN of short-range connections. Compared to HC, the FA of three fibers in RRMS and NMOSD were reduced significantly, and the decrease of FA in RRMS was greater than in NMOSD. There were correlations between the FN of short-, and long-range connections and the atrophy of whole brain tissue in two diseases and structural network topological parameters in RRMS. Additionally, there was no significant difference of FN and FA in short-, middle- and long-range connections between the baseline and follow-up in two diseases. RRMS and NMOSD patients have different patterns of fiber connection damage. The FN of different lengths in RRMS and NMOSD patients may be associated with brain atrophy. The FN and FA of different lengths may explain the decreased efficiency of the structural network in RRMS patients. In the short-term follow-up, neither has worsened damage of different fibers in two diseases.

Whole-genome sequence-based association analyses on an eight-breed crossed heterogeneous stock of pigs reveal the genetic basis of skeletal muscle fiber characteristics

Skeletal muscle fiber characteristics (MFCs) have been extensively studied due to their importance to human health and athletic ability, as well as to the quantity and quality of livestock meat production. Hence, we performed a genome-wide association study (GWAS) on nine muscle fiber traits by using whole genome sequence data in an eight-breed crossed heterogeneous stock pig population. This GWAS revealed 67 quantitative trait loci (QTLs) for these traits. The most significant GWAS signal was detected in the region of Sus scrofa chromosome 12 (SSC12) containing the MYH gene family. Notably, we identified a significant SNP rs322008693 (P = 7.52E-09) as the most likely causal mutation for the total number of muscle fibers (TNMF) QTL on SSC1. The results of EMSA and luciferase assays indicated that the rs322008693 SNP resided in a functional element. These findings provide valuable molecular markers for pig meat production selection as well as for deciphering the genetic mechanisms of the muscle fiber physiology.

Effects of intramuscular fat on meat quality and its regulation mechanism in Tan sheep.

Intramuscular fat (IMF) contributes importantly to various aspects of meat quality, and genetic regulation is an effective pathway to improve IMF deposition in sheep. In this study, we systematically explored the effect of IMF content on meat quality in Tan sheep and investigated the regulatory mechanism of flavor precursors metabolism and IMF deposition. The results revealed that IMF significantly affected meat color, total muscle fiber numbers, and muscle fiber types in Tan sheep. Widely-targeted metabolomic analysis showed that amino acids were the main differential flavor precursors between lambs with different IMF content. Importantly, the comparison of fatty acid profiles revealed that saturated fatty acids and monounsaturated fatty acids are beneficial for IMF deposition. Furthermore, integrated analysis between metabolome and transcriptome indicated that MME is a key gene resulting in the reduction of amino acids in lambs with high IMF content; and the joint analysis between fatty acid profiles and transcript profiles showed that ADIPOQ, FABP4, PLIN1, PPARGC1A, SLC2A1 accelerated IMF deposition through positive regulation of saturated fatty acids and monounsaturated fatty acids metabolism. These results revealed key changes in meat quality affected by IMF content and the corresponding genetic mechanism, which may provide a new insight for understanding the IMF differential deposition and for improving meat quality in Tan sheep.

A new concept of the fiber composition of cervical spinal dura mater: an investigation utilizing the P45 sheet plastination technique

PurposeFew reports have been published regarding the microanatomy of the dura mater located at the craniovertebral junction (CVJ). In clinic, the precise microanatomy of the CVJ dura mater would be taken into account, for reducing surgical complications and ineffective surgical outcomes. The main objective of the present investigation was to further elucidate the fiber composition and sources of the cervical spinal dura mater.MethodsThe formalin-fixed adult head and neck specimens (n = 21) were obtained and P45 plastinated section method was utilized for the present study. The fibers of the upper cervical spinal dura mater (SDM) were examined in the P45 sagittal sections in the CVJ area. All photographic documentation was performed via a Canon EOS 7D Mark camera.ResultsThe posterior wall of the SDM sac at CVJ was found to be composed of stratified fibers, which are derived from three sources: the cerebral dura mater, the occipital periosteum, and the myodural bridge (MDB). The proper layer of the cerebral dura mater passes over the brim of the foramen magnum and enters the vertebral canal to form the inner layer of the SDM, and the fibers originating from the periosteum of the brim of the foramen magnum form the middle layer. The fibers of the MDB are inserted into the SDM and form its outer layer. It was found that the total number of fibers from each origin varied in humans.ConclusionAt the CVJ, the posterior wall of the SDM is a multi-layered structure composed of three different originated fibers. The cerebral dura mater, the periosteum located at the brim of the foramen magnum, and MDB contribute to the formation of the SDM. The present study would be beneficial to the choice of surgical approach at the CVJ and the protection of the SDB.

Lidocaine Nerve Block Diminishes the Effects of Therapeutic Electrical Stimulation to Enhance Nerve Regeneration in Rats.

Although electrical stimulation (ES) can improve nerve regeneration, the impact of nerve block, such as lidocaine (Lido), on the therapeutic benefits of ES remains unclear. We used a rat tibial nerve transection-and-repair model to explore how either preoperative (PreOp) or postoperative (PostOp) nerve block affects ES-related improvement in regeneration. Lewis rats were used in 1 of 2 studies. The first evaluated the effects of extraneural Lido on both healthy and injured nerves. In the second study, rats were randomized to 5 experimental groups: No ES (negative control), PreOp Lido, ES + PreOp Lido, PostOp + ES, and ES (positive control). All groups underwent tibial nerve transection and repair. In both studies, nerves were harvested for histological analysis of regeneration distal to the injury site. Application of extraneural Lido did not damage healthy or injured nerve based on qualitative histological observations. In the context of nerve transection and repair, the ES group exhibited improved axon regeneration at 21 days measured by the total number of myelinated fibers compared with No ES. Fiber density and percentage of neural tissue in the ES group were greater than those in both No ES and PreOp Lido + ES groups. ES + PostOp Lido was not different from No ES or ES group. Extraneural application of Lido did not damage nerves. Electrical stimulation augmented nerve regeneration, but Lido diminished the ES-related improvement in nerve regeneration. Clinical studies on the effects of ES to nerve regeneration may need to consider nerve block as a variable affecting ES outcome.

Comment on: Purifying air over the operating field with a new mobile laminar airflow device to reduce the possibility of airborne contamination.

We were interested to read the recent article by Osher et al.1 We had also previously reviewed the poster by Osher and Figueiredo, “A New Technology for Purifying the Surgical Field”, at the 2019 ASCRS Annual Meeting in San Diego that had a nice picture of the Operio System located adjacent to the patient and the surgical field. Point 1, we wish that photograph had been included in this article and the reason for the orientation or of the machine discussed further in the article. Prior to the San Diego meeting, we became concerned with the plethora of lint-like fibers on the surgical field at our institution, both clear and blue, particularly after visualizing one in Bela Lugosi-like horror in the anterior chamber on the first postoperative day (Figure 1). After recovery and ensuring that the patient did not develop endophthalmitis, we initiated a Quality Assurance Project that sought to identify the number, risk factors, and location of these fibers during a senior resident's 3-month surgical rotation (A.H.). Eighty-nine surgeries were performed between the attending and the senior resident, and 15 fibers were identified. Most fibers were seen on the approach to the eye as an instrument was inserted, but 7 were seen in the eye during nucleus manipulation, capsulorhexis, and cortex removal. Similar to the article by Osher et al., we had no episodes of toxic anterior segment syndrome, chronic uveitis, or endophthalmitis (Table 1).Figure 1 Table 1. - Fiber Location During Phacoemulsification Surgery. Cataract procedure step Cases, n Intracameral moxifloxacin injection 3 Cortex removal 3 Capsulorhexis 2 Nuclear cracking and manipulation 2 Wound closure 2 IOL injection 1 Viscoelastic removal 1 Trabecular microbypass device 1 Regarding Table 2, the denominator is 99 in the laminar flow group and 50 in the control group. We noted on initial review that the total number of fibers seen in the laminar air flow group was 13 in 99 eyes vs the control group of 16 in 50 eyes, which is only a difference of 3, which if we increased the denominator to 100 in the control group, the total number of fibers would probably double. In personal communication with the primary author, it became clear that the salient point that the article conveyed is that in the laminar air flow group, the number of fibers directly on the field was zero. In other words, all fibers in the laminar air flow group were brought onto the surgical field by an instrument that is similar to our small series, which had a very high fiber rate of 16.9%. Watson et al. in their comment on this article focus on the trend to move toward office-based surgery and they discuss a laminar downflow hood that they have been using for 1 year.2 As such, Osher et al. and Watson et al. should be complimented for addressing important factors in our surgical microenvironments including air flow, ventilation systems, the revolving door-like atmosphere in a teaching environment, and our drapes and gowns. Point 2, we would go further, like our orthopedic colleagues, to attempt to close our operating rooms to transit to protect the laminar flow, locate our automated medication dispensing systems inside our operating rooms, and recommend that we seek to eliminate or find alternatives to article and cloth-based drapes and towels. We support the efforts by Osher et al. to eliminate what we aptly defined in our Quality Assurance Project as “Fibers, Fibers, Everywhere!”

Influence of fibers distribution on direct shear and flexural behavior of synthetic fiber-reinforced self-compacting concrete

The influence of fiber distribution on the direct shear and flexural behavior of Fiber-Reinforced Self-Compacting Concrete (FR-SCC) is investigated. This study characterizes FR-SCC reinforced with monofilament polypropylene fiber (P) and kinked multifilament polypropylene/polyethylene fiber (PP) at volumes of 0.6, 0.8, and 1.0%. The loss of workability in the FR-SCC mixtures increased the variation in the distribution of the fibers. The residual flexural strength and direct shear toughness increased linearly with the total number of fibers exposed on fracture cross-sections. In general, the P fiber provided better mechanical performance than the PP fiber due to its anchorage effectiveness, which improved the transfer of stress from the matrix to the fiber.