Varying of up-conversion nanoparticles luminescence from the muscle tissue depth during the compression

The current work is focused on the study of optical clearing of skeletal muscles under local compression.The experiments were performed on in vitro bovine skeletal muscle.The time dependence of optical clearing was studied by monitoring the luminescence intensity of NaYF_(4)∶Er,Yb upconverting particles located under tissue layers.This study shows the possibility to use upconverting nanoparticles(UCNPs)both for studying the dynamics of the optical clearing of biological tissue under compression and to detect moments of cell wall damage under excessive pressure.The advantage of using UCNPs is the presence of several bands in their luminescence spectra,located both at close wavelengths and far apart.

Three‑dimensional Modeling and Simulation of Muscle Tissue Puncture Process

Needle biopsy is an essential part of modern clinical medicine.The puncture accuracy and sampling success rate of puncture surgery can be effectively improved through virtual surgery.There are few three-dimensional puncture(3D)models,which have little significance for surgical guidance under complicated conditions and restrict the development of virtual surgery.In this paper,a 3D simulation of the muscle tissue puncture process is studied.Firstly,the mechanical properties of muscle tissue are measured.The Mooney-Rivlin(M-R)model is selected by considering the fitting accuracy and calculation speed.Subsequently,an accurate 3D dynamic puncture model is established.The failure criterion is used to define the breaking characteristics of the muscle,and the bilinear cohesion model defines the breaking process.Experiments with different puncture speeds are carried out through the built in vitro puncture platform.The experimental results are compared with the simulation results.The experimental and simulated reaction force curves are highly consistent,which verifies the accuracy of the model.Finally,the model under different parameters is studied.The simulation results of varying puncture depths and puncture speeds are analyzed.The 3D puncture model can provide more accurate model support for virtual surgery and help improve the success rate of puncture surgery.

Effects of high‑grain diet feeding on fatty acid profiles in milk,blood,muscle,and adipose tissue,and transcriptional expression of lipid‑related genes in muscle and adipose tissue of dairy cows

Background High-grain(HG)diets affect lipid metabolism in the liver and mammary tissue of dairy cows,but its effects on muscle and adipose tissue have not been wide evaluated.Thus,the aim of this study is to clarify this issue.Methods Twelve Holstein cows were randomly divided into two groups:conventional diet group(CON,n=6)and the HG diet group(n=6).On day 7 of week 4,rumen fluid was sampled to measure pH,milk was sampled to meas-ure components,and blood was sampled to measure biochemical parameters and fatty acid composition.After the experiment,cows were slaughtered to collect muscle and adipose tissue for fatty acid composition and transcriptome analysis.Results HG feeding decreased the ruminal pH,milk’s fat content and long-chain fatty acid proportion(P<0.05)and increased the proportion of short-and medium-chain fatty acids in the milk(P<0.05)as compared with CON diets.The concentrations of blood cholesterol,low-density lipoprotein,and polyunsaturated fatty acids in the HG cows were lower than those in CON cows(P<0.05).In muscle tissue,HG feeding tended to increase the triacylglycerol(TG)concentration(P<0.10).Transcriptome analysis revealed changes in the biosynthesis of the unsaturated fatty acids pathway,the regulation of lipolysis in the adipocytes pathway,and the PPAR signalling pathway.In adipose tissue,HG feeding increased the concentration of TG and decreased the concentration of C18:1 cis9(P<0.05).At the transcrip-tome level,the fatty acid biosynthesis pathway,linoleic acid metabolism pathway,and PPAR signalling pathway were activated.Conclusion HG feeding leads to subacute rumen acidosis and a decreased milk fat content.The fatty acid profiles in the milk and plasma of dairy cows were changed by HG feeding.In muscle and adipose tissue,HG feeding increased TG concentration and up-regulated the expression of genes related to adipogenesis,while down-regulated the expression of genes related to lipid transport.These results complement our knowledge of the fatty acid composi-tion of muscle and adipose tissue in dairy cows and expand our understanding of the mechanisms by which HG diets affect lipid metabolism in muscle and adipose tissue.

Direct-writing Process and in vivo Evaluation of Prevascularized Composite Constructs for Muscle Tissue Engineering Application

Tissue engineered skeletal muscle is expected to treat muscle defects caused by trauma and disease.However,designing and manufacturing thick and complex tissue engineered skeletal muscle requires vascularization to ensure its internal cell viability and nutrient supply in vitro.In this article,we developed a set of Direct-Writing(DW)bio-printing procedure to manufacture a prevascularized composite construct with Human Umbilical Vein Endothelial Cell(HUVEC)and C2C12 cells for muscle tissue engineering application.We put the cells into the construct during the DW process to obtain the prevascularization and intend to promote its vascularization in vivo later.The constructs with cells or without cells were implanted respectively into nude mice back for 3 weeks,after which the mice healthily live for all the time and all the implants are tightly bonded to the host.From immunohistochemical analysis,CD31-positive blood vessels existed in the implanted samples with cells are more substantial than those without cells,but the implanted samples with HUVEC and C2C12 cells have much more number of small blood vessels distributing evenly.Moreover,the implants with cells,especially that with HUVEC and C2C12 cells,are able to get better fusion with the host skin and subcutaneous tissues.Histological analysis demonstrates that our DW-based constructs have the potential to be getting to vascularize the tissue engineered muscle.

Disseminated soft tissue diffuse large B-cell lymphoma involving multiple abdominal wall muscles:A case report

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is the most common subtype of non�Hodgkin lymphoma,and patients with DLBCL typically present rapidly growing masses.Lymphoma involving muscle is rare and accounts for only 5%;furthermore,multiple muscles and soft tissue involvement of DLBCL is unusual.Due to unusual clinical manifestation,accurate diagnosis could be delayed.CASE SUMMARY A 61-year-old man complained of swelling,pain and erythematous changes in the lower abdomen.Initially,soft tissue infection was suspected,however,skin lesion did not respond to antibiotics.18Fluoro-2-deoxy-D-glucose(18F-FDG)positron emission tomography-computed tomography demonstrated FDG uptake not only in the skin and subcutaneous tissue of the abdomen but also in the abdominal wall muscles,peritoneum,perineum,penis and testis.DLBCL was confirmed by biopsy of the abdominal wall muscle and subcutaneous tissue.After intensive treatment including chemotherapy with rituximab,cyclophosphamide,doxorubicin,vincristine and prednisolone,central nervous system prophylaxis(intrathecal injection of methotrexate,cytarabine and hydrocortisone)and orchiectomy,he underwent peripheral blood stem cell mobilization for an autologous hematopoietic stem cell transplantation.Despite intensive treatment,the disease progressed rapidly and the patient showed poor outcome(overall survival,9 mo;disease free survival,3 mo).CONCLUSION The first clinical manifestation of soft tissue DLBCL involving multiple muscles was similar to the infection of the soft tissue.

Applied distally based peroneus brevis muscle flaps for coverage of the soft tissue defects over the lower one-third of the leg, ankle and foot

Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applied for coverage of the soft tissue defects over the lower one-third of the leg,the ankle and the foot. The muscle flaps were covered with split-thickness skin grafts. Results The distally based peroneus brevis muscle flaps were applied for coverage of the soft tissue defects over the lower one-third of the leg, the ankle and the foot in 16 cases. The larges area of the soft tissue defect was 5 cm × 7 cm. The smallest was 3 cm × 4 cm. Primary healing occured in 14 cases undergoing muscle flap construction, second-stage healing occured in 2 cases, no total flap necrosis occured in any cases. Conclusion ThisChina Medical Abstracts(Surgery) technigue is a simple and complication are lesser. The successful rates are higher. This muscle flap is suitable to the mudium or small soft tissue

Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis

Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous stiffness.Interestingly,these effects were also reported in response to various other active and passive interventions that induce responses such as enhanced muscle temperature.Therefore,we hypothesized that acute ROM enhancements could be induced by a wide variety of interventions other than stretching or foam rolling that promote an increase in muscle temperature.Methods:After a systematic search in PubMed,Web of Science,and SPORTDiscus databases,38 studies comparing the effects of stretching and foam rolling with several other interventions on ROM and passive properties were included.These studies had 1134 participants in total,and the data analysis resulted in 140 effect sizes(ESs).ES calculations were performed using robust variance estimation model with R-package.Results:Study quality of the included studies was classified as fair(PEDro score=4.58)with low to moderate certainty of evidence.Results showed no significant differences in ROM(ES=0.01,p=0.88),stiffness(ES=0.09,p=0.67),or passive peak torque(ES=-0.30,p=0.14)between stretching or foam rolling and the other identified activities.Funnel plots revealed no publication bias.Conclusion:Based on current literature,our results challenge the established view on stretching and foam rolling as a recommended component of warm-up programs.The lack of significant difference between interventions suggests there is no need to emphasize stretching or foam rolling to induce acute ROM,passive peak torque increases,or stiffness reductions.

Generation and Analysis of Expressed Sequence Tags(ESTs) from Muscle Full-Length cDNA Library of Wujin Pig

Porcine skeletal muscle genes play a major role in determining muscle growth and meat quality. Construction of a full-length cDNA library is an effective way to understand the expression of functional genes in muscle tissues. In addition, novel genes for further research could be identified in the library. In this study, we constructed a full-length cDNA library from porcine muscle tissue. The estimated average size of the cDNA inserts was 1 076 bp, and the cDNA fullness ratio was 86.2%. A total of 1 058 unique sequences with 342 contigs （32.3%） and 716 singleton （67.7%） expressed sequence tags （EST） were obtained by clustering and assembling. Meanwhile, 826 （78.1%） ESTs were categorized as known genes, and 232 （21.9%） ESTs were categorized as unknown genes. 65 novel porcine genes that exhibit no identity in the TIGR gene index of Sus scrofa and 124 full-length sequences with unknown functions were deposited in the dbEST division of GenBank （accession numbers： EU650784-EU650788, GE843306, GH228978-GH229100）. The abundantly expressed genes in porcine muscle tissue were related to muscle fiber development, energy metabolism and protein synthesis. Gene ontology analysis showed that sequences expressed in porcine muscle tissue contained a high percentage of binding activity, catalytic activity, structural molecule activity and motor activity, which involved mainly in metabolic, cellular and developmental process, distributed mainly in intracellular region. The sequence data generated in this study would provide valuable information for identifying porcine genes expressed in muscle tissue and help to advance the study on the structure and function of genes in pigs.

Comparative study on in vitro transformation of paralytic shellfish poisoning (PSP) toxins in different shellfish tissues

Dissected tissues of three shellfish species, the Chinese scallop, Chlamys farreri, Manila clam, Ruditapes philippinarurn, and Razor shell, Solen strictu were evaluated for in vitro transformation of paralytic shellfish poisoning （PSP） toxins. Tissue homogenates were incubated with extraction from toxic algae Alexandriurn rninutura to determine toxin conversion. The effects of heating and addition of a natural reductant （glutathione） on toxin conversion were also assessed. The toxin profile was investigated through high performance liquid chromatography with fluorescence detection （HPLC-FLD）. The evident variations in the toxin content were observed only in Chinese scallop viscera homogenates. The concentration of GTX4 was reduced by 45% （approximately 0.8 μmol/dm^3） and 25% （approximately 1 μmol/dm^3） for GTX1, while GTX2 and GTX3 increased by six times （approximately 1 μmol/dm^3） and 3 times （approximately 0.3μmol/dm^3） respectively. Simultaneously, the total toxicity decreased by 38% during the 48 h incubation period, the final toxicity was 20.4 nmol STXeq/g. Furthermore, heated Chinese scallop viscera homogenates samples were compared with non-heated samples. The concentration of the GTX4 and GTX1 was clearly 28% （approximately 0.53 μmol/dm^3） and 17% （approximately 0.69μmol/dm^3） higher in heated samples, GTX2 and GTX3 were four times （0.66 μmol/dm^3） and two times （0.187 μmol/dm^3） lower respectively. GSH （＋） Chinese scallop viscera homogenates samples were compared with GSH （-） samples, the concentration in the GTX4 and GTX1 was 9% （approximately 0.12 μmol/dm^3） and 11% （approximately 0.36 μmol/dm^3） lower respectively, GTX2 and GTX3 was 17% （approximately 0.14 μmol/dm^3） and 19% （approximately 0.006 μmol/dm^3） higher respectively. In contrast,there was a little change in the concentration of PSP toxins of Manila clam and Razor shell tissue ho- mogenates. These observations on three shellfish tissues confirmed that there were species-specific differences in PSP toxins transformation. PSP toxins transformation was more pronounced in viscera tissue than in muscle tissue. PSP toxins was possibly interfered by some carbamoylase enzyme, and the activity in Chinese scallop viscera tissue is more remarkable than in the other two species.

Muscle Biological Characteristics of Differentially Expressed Genes in Wujin and Landrace Pigs

The biological chemistry would be responsible for the meat quality. This study tried to investigate the transcript expression profile and explain the characteristics of differentially expressed genes between the Wujin and Landrace pigs. The results showed that 526 differentially expressed genes were found by comparing the transcript expression profile of muscle tissue between Wujin and Landrace pigs. Among them, 335 genes showed up-regulations and 191 genes showed down-regulations in Wujin pigs compared with the Landrace pigs. Gene ontology （GO） analysis indicated that the differentially expressed genes were clustered into three groups involving in protein synthesis, energy metabolism and immune response. Kyoto encyclopedia of genes and genomes （KEGG） pathway analysis found that these differentially expressed genes participated in protein synthesis metabolism, energy metabolism and immune response pathway. The Database for Annotation, Visualization and Integrated Discovery （DAVID） analysis of protein function and protein domains function also confirmed that differentially expressed genes belonged to protein synthesis, energy metabolism and immune response. Genes related protein synthesis metabolism pathway in Landrace was higher than in Wujin pigs. However, differentially expressed genes related energy metabolism and immune response was up-regulated in Wujin pigs compared with Landrace pigs. Quantitative real-time RT-PCR on selected genes was used to confirm the results from the microarray. These suggested that the genes related to protein synthesis, energy metabolism and immune response would contribute to the growth performance, meat quality as well as anti-disease capacity.

Artificial meat? Feasible approach based on the experience from cell culture studies

This short review is to list pros and cons which are based on the literature and personal experience in cell culture studies related to possible commercial production of artificial meat as functional food. The general view of muscle composition and determinants of meat quality are shortly described. Principles of muscle cell propagation in culture and mutual relationships between different cell types present in this organ are briefly discussed. Additionally, the effects of some cytokines and growth factors for muscle cell growth and muscle tissue development are indicated. Finally, conclusion remarks related to detrimental consequences of meat production to natural environment as well as personal opinion of author on the prospects of artificial meat production are declared.

Biomimetic glycosaminoglycan-based scaffolds improve skeletal muscle regeneration in a Murine volumetric muscle loss model

Volumetric muscle loss(VML)injuries characterized by critical loss of skeletal muscle tissues result in severe functional impairment.Current treatments involving use of muscle grafts are limited by tissue availability and donor site morbidity.In this study,we designed and synthesized an implantable glycosaminoglycan-based hydrogel system consisting of thiolated hyaluronic acid(HA)and thiolated chondroitin sulfate(CS)cross-linked with poly(ethylene glycol)diacrylate to promote skeletal muscle regeneration of VML injuries in mice.The HA-CS hydrogels were optimized with suitable biophysical properties by fine-tuning degree of thiol group substitution to support C2C12 myoblast proliferation,myogenic differentiation and expression of myogenic markers MyoD,MyoG and MYH8.Furthermore,in vivo studies using a murine quadriceps VML model demonstrated that the HA-CS hydrogels supported integration of implants with the surrounding host tissue and facilitated migration of Pax7+satellite cells,de novo myofiber formation,angiogenesis,and innervation with minimized scar tissue formation during 4-week implantation.The hydrogel-treated and autograft-treated mice showed similar functional improvements in treadmill performance as early as 1-week post-implantation compared to the untreated groups.Taken together,our results demonstrate the promise of HA-CS hydrogels as regenerative engineering matrices to accelerate healing of skeletal muscle injuries.

In Vivo Study on Degradation Behavior and Histologic Response of Pure Magnesium in Muscles

When an orthopedics device is implanted into bone injury site, it will contact the soft tissue （skeletal muscle, fascia, ligament etc.） except for bone. Magnesium based biodegradable metals are becoming an important research object in orthopedics due to their bioactivity to promote bone healing. In this study, pure Mg rods with and without chemical conversion coating were implanted into the muscle tissue of rabbits. Implants and their surrounding tissues were taken out for weight loss measurement, cross- sectional scanning electron microscopy observation, elemental distribution analysis and histological examination. The results showed that the chemical conversion coating would increase the in vivo cor- rosion resistance of pure Mg and decrease the accumulation of calcium （Ca） and phosphorus （P） elements around the implants. For the bare magnesium implant, both Ca and P contents in the surrounding tissues increased at the initial stage of implantation and then decreased at 12 weeks implantation, while for the magnesium with chemical conversion coating, Ca and P contents in the surrounding tissues de- creased with the implantation time, but were not significant. The histological results demonstrated that there was no calcification in the muscle tissue with implantation of magnesium for up to 12 weeks. The chemical conversion coating not only increased the in vivo corrosion resistance of pure Mg, but also avoided the depositions of Ca and P in the surrounding tissues, meaning that pure magnesium should be biosafe when contacting with muscle tissues,

Preparation and Endothelialization of Multi-level Vessel-like Network in Enzymated Gelatin Scaffolds

Loss of function of large tissues is an urgent clinical problem. Although the artificial microfluidic network fabricated in large tis- sue-engineered constructs has great promise, it is still difficult to develop an efficient vessel-like design to meet the requirements of the biomimetic vascular network for tissue engineering applications. In this study, we used a facile approach to fabricate a branched and multi-level vessel-like network in a large muscle scaffolds by combining stereolithography （SL） technology and enzymatic crosslinking mechanism. The morphology of microchannel cross-sections was characterized using micro-computed tomography. The square cross-sections were gradually changed to a seamless circular microfluidic network, which is similar to the natural blood vessel. In the different micro-channels, the velocity greatly affected the attachment and spread of Human Umbilical Vein Endothelial Cell （HUVEC）-Green Fluorescent Protein （GFP）. Our study demonstrated that the branched and multi-level microchannel network simulates biomimetic microenvironments to promote endothelialization. The gelatin scaffolds in the circular vessel-like networks will likely support myoblast and surrounding tissue for clinical use.

Analysis of monomeric and oligomeric organophosphorus flame retardants in fish muscle tissues using liquid chromatographyeelectrospray ionization tandem mass spectrometry:Application to Nile tilapia(Oreochromis niloticus)from an e-waste processing area in northern Vietnam

Using electrospray ionization tandem mass spectrometry combined with liquid chromatography(LC),a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants(m-PFRs)and three oligomeric organophosphorus flame retardants(o-PFRs)in fish muscle samples.The optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle samples.The recoveries of analytes in fish muscle samples were in the range of 74-105%.The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6-8.9%.The concentrations of analytes in procedural blanks were below the limit of quantification(LOQ)values.Furthermore,the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste(ewaste)processing area in northern Vietnam.The concentrations of m-PFRs such as tris(2-chloroethyl)phosphate(TCEP),tris(2-chloroisopropyl)phosphate(TCIPP),and triphenyl phosphate(TPHP)were dominant among the investigated m-PFRs.The respective concentrations of TCEP,TCIPP,and TPHP were up to 160,300,and 230 ng g^-1 lipid weight,respectively,whereas those of o-PFRs were up to 10 ng g^-1 lipid weight.The results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.