Bovine Muscle Tissue Research Articles

Imaging high-intensity focused ultrasound-induced tissue denaturation by multispectral photoacoustic method: an ex vivo study

We present an ex vivo study for the first time, to the best of our knowledge, in multispectral photoacoustic imaging (PAI) of tissue denaturation induced by high-intensity focused ultrasound (HIFU) in this paper. Tissue of bovine muscle was thermally treated in a heated water bath and by HIFU, and then was imaged using a multispectral photoacoustic approach. Light at multiple optical wavelengths between 700 and 900 nm was delivered to the treated bovine muscle tissue to excite the photoacoustic signal. Apparent tissue denaturation has been observed in multispectral photoacoustic images after being treated in a water bath and by HIFU. It is interesting that the denaturation is more striking at shorter optical wavelength photoacoustic images than at longer optical wavelength photoacoustic images. Multispectral photoacoustic images of the tissue denaturation were further analyzed and the photoacoustic spectrums of the denaturized tissue were calculated in this paper. This study suggests that a multispectral PAI approach might be a promising tool to evaluate tissue denaturation induced by HIFU treatment.

Identification and profiling of conserved and novel microRNAs from Chinese Qinchuan bovine longissimus thoracis

BackgroundMicroRNAs (miRNAs) are a family of ~22 nucleotide small RNA molecules that regulate gene expression by fully or partially binding to their complementary sequences. Recently, a large number of miRNAs and their expression patterns have been identified in various species. However, to date no miRNAs have been reported to modulate muscle development in beef cattle.ResultsTotal RNAs from the Chinese Qinchuan bovine longissimus thoracis at fetal and adult stages were used to construct small RNA libraries for Solexa SBS technology sequencing. A total of 15,454,182 clean reads were obtained from the fetal bovine library and 13,558,164 clean reads from the adult bovine library. In total, 521 miRNAs including 104 novel miRNA candidates were identified. Furthermore, the nucleotide bias, base edit and family of the known miRNAs were also analyzed. Based on stem-loop qPCR, 25 high-read miRNAs were detected, and the results showed that bta-miRNA-206, miRNA-1, miRNA-133, miRNAn12, and miRNAn17 were highly expressed in muscle-related tissue or organs, suggesting that these miRNAs may play a role in the development of bovine muscle tissues.ConclusionsThis study confirmed the authenticity of 417 known miRNAs, discovered 104 novel miRNAs in bos taurus, and identified five muscle-specific miRNAs. The identification of novel miRNAs significantly expanded the repertoire of bovine miRNAs and could contribute to further studies on the muscle development of cattle.

Technique for measuring laser radiation intensity in biological tissues

AbstractLaser methods, such as laser-induced fluorescence diagnostics, photodynamic therapy (PDT), and hyperthermia, are finding increasing use in medicine. Irradiation can be performed both with and without contact on the tissue surface. In the case of contact irradiation, especially when laser radiation is introduced into biological tissue through an optical fiber, it is important to know the processes taking place at the irradiation fiber end. These processes affect diffusely reflected radiation which returns to the fiber. By analyzing backscattered radiation, we can evaluate the quality of the radiation procedure and the state of the fiber end. The objectives of this study were to develop a method and device for measuring backscattered radiation power and using this method, to determine the time and temperature ranges realized in PDT and hyperthermia.Light propagation is discussed in bent optical fibers. A technique is proposed for measuring laser radiation intensity in the optical fiber bend. Based on this technique, a system was developed for monitoring the laser radiation dose absorbed in biological tissues. We studied samples of bovine liver, muscle and brain tissues. Experiments were performed using a 675 nm, 100–2200 mW continuous wave semi-conductor laser. Laser radiation was delivered through a silica/polymer optical fiber. Data concerning the temperature and transmitted radiation intensity was acquired.Modeling of the light propagation in a bent optical fiber showed that the sensitivity of the method depends on the position of the photodetectors, but is independent of the loop number of the optical fiber. The results of experiments are presented using different types of biological tissues. We obtained the experimental dependencies of backward and transmitted radiation intensities and the temperature of the tissue surface in the irradiated region on the irradiation time measured with a flat-end fiber. The characteristic ranges of tissue heating caused by irradiation were determined for use in clinical practice.The optical parameters of biological tissues change with increasing temperature. This affects the intensity of transmitting radiation and diffuse radiation entering the fiber. The change in the backscattered radiation intensity greatly depend on the temperature of the irradiated area. The control of the irradiation of biological objects provides an efficient delivery of laser radiation to biological tissues and increases hyperthermia and PDT treatment effect.

Determination of Zeranol and its Metabolites in Bovine Muscle Tissue with Gas Chromatography-Mass Spectrometry

Abstract This paper describes the quantitative method of determination of chosen substances from resorcylic acid lactones group: zeranol, taleranol, α-zearalenol, β-zearalenol, and zearalanone in bovine muscle tissue. The presented method is based on double diethyl ether liquid-liquid extraction (LLE), solid phase extraction (SPE) clean up, and gas chromatography mass spectrometry (GC-MS) analysis. The residues were derivatised with a mixture of N-methyl-N-trimethylsilyltrifluoroacetamide, ammonium iodide, and DL-dithiothreitol (1,000:2:5, v/w/w). The GC-MS apparatus was operated in positive electron ionisation mode. The method was validated according to the European Union performance criteria pointed in Decision Commission 2002/657/EC. The average recoveries of all analytes at 1 μg kg-1 level were located between 83.7% and 94.5% values with the coefficients of variation values <25%. The decision limits (CCα) and detection capabilities (CCβ) for all analytes ranged from 0.58 to 0.82 μg kg-1 and from 0.64 to 0.94 μg kg-1, respectively. The procedure has been accredited and is used as a screening and confirmatory method in control of hormone residues in animal tissues.

Comparative Evaluation of Calcium Hypochlorite and Sodium Hypochlorite on Soft-tissue Dissolution

IntroductionThe aim of this study was to compare in vitro the tissue-dissolution properties of 5% and 10% calcium hypochlorite (Ca(OCl)2) with two concentrations (1.36% and 4.65%) of proprietary sodium hypochlorite (NaOCl) on bovine muscle tissue. MethodsThe available chlorine concentration of each solution was determined using iodometric titration. Tissue specimens from bovine muscle were weight adjusted (50 ± 5 mg). Ten tissue specimens in each group were immersed in 5 mL each test solution, removed after 5 minutes, blotted dry, and weighed. The process was repeated every 5 minutes with a fresh 5-mL aliquot of the test solution for 60 minutes or until complete tissue dissolution, whichever was quickest. The percentage weight loss of the specimens was calculated over the experimental period. ResultsAvailable chlorine concentrations of the irrigants ranged from 1.36% to 4.65%. All solutions dissolved tissue completely after 60 minutes except 5% Ca(OCl)2 (99.4% dissolution). Between the 35- and 60-minute test readings, there were no significant differences between the solutions. Chlorax (4.65% NaOCl) (Cerkamed Group, Nisko, Poland) dissolved tissue quicker during the first 35 minutes (P < .05). In this period, the weight loss with 10% Ca(OCl)2 differed from Chlorax at all time intervals except at 5 and 35 minutes (P < .05); 5% Ca(OCl)2 showed no significant differences with 10% Ca(OCl)2 and Tesco bleach (1.36% NaOCl) (Tesco Stores Ltd, Chestnut, UK) in the first 35 minutes except at the 5-minute measurement. ConclusionsWithin the limitations of this study, Chlorax (4.65% NaOCl) dissolved tissue faster than the Ca(OCl)2 solutions and Tesco thin bleach (1.36% NaOCl) over the first 35 minutes, but there were no significant differences among the solutions thereafter.

Multi residue determination of the penicillins regulated by the European Union, in bovine, porcine and chicken muscle, by LC–MS/MS

A multiresidue analysis method was developed to determine the content of penicillins in bovine, porcine and chicken muscle tissues. The procedure involves solid phase extraction (SPE) and subsequent analysis by liquid chromatography coupled with tandem mass spectrometry detection (LC–MS/MS) set by the European Union (EU) for all compounds. The method was validated according to EU guideline 2002/657/EC. The LOQ in tissues are below the maximum residue limits (MRLs) and appropriate quality parameters in terms of linearity, accuracy (recoveries higher than 70% for all antibiotics and animal tissues except for AMOX with 50% of recovery) and precision (in terms of intra and inter day with values lower than 12% in all cases) are obtained for the developed method.A study concerning to the matrix effect was made and it was concluded that similar matrix effect could be found in beef, pig and chicken.The method was applied to the analysis of samples of chicken from animals treated with amoxicillin.

Development and validation of two multiresidue liquid chromatography tandem mass spectrometry methods based on a versatile extraction procedure for isolating non-steroidal anti-inflammatory drugs from bovine milk and muscle tissue

The main difficulties in analysing non-steroidal anti-inflammatory drugs (NSAIDs) in food and biological samples are due to the tight non-covalent interactions established with matrix proteins and the amount of occurring fatty material. The present paper describes an effective extraction procedure able to isolate fifteen NSAIDs (acetaminophen, salicylic acid, ibuprofen, diclofenac, flunixin and its metabolite 5-hydroxy-flunixin, nimesulide, phenylbutazone, meclofenamic acid, tolfenamic acid, meloxicam, carprofen, ketoprofen, naproxen and etodolac) from bovine milk and muscle tissue through two succeeding steps: (a) deproteinisation/extraction with organic solvent, essential to lower the medium dielectric constant and, therefore, to release the analytes from matrix; (b) SPE clean-up on OASIS cartridges. Lipids were easily removed during low-temperature centrifugations. The advantages of the developed procedure pertain to the efficient removal of the fat substances (very low matrix effect and high recovery yields) and its versatility, since it can be applied both to milk and muscle with few adjustments due to the diversity of the two matrices. Ion-pairing reversed-phase chromatography combined with the negative electrospray detection was able to achieve low detection capabilities (CCβs) for all analytes and, in particular, for diclofenac whose Maximum Residue Limit (MRL) in milk is 0.1 μg kg(-1). The methods were validated according to the guidelines of the Commission Decision 2002/657/EC and then applied for a small monitoring study. A number of samples showed traces of salicylic acid (SA), but its occurrence was not ascribed to a misuse of drugs (aspirin, salicylic acid) since SA, accumulating in plants in response to a pathogen attack, may be introduced into the food chain.

Depot-specific gene expression profiles during differentiation and transdifferentiation of bovine muscle satellite cells, and differentiation of preadipocytes

We report a systematic study of gene expression during myogenesis and transdifferentiation in four bovine muscle tissues and of adipogenesis in three bovine fat tissues using DNA microarray analysis. One hundred hybridizations were performed and 7245 genes of known and unknown function were identified as being differentially expressed. Supervised hierarchical cluster analysis of gene expression patterns revealed the tissue specificity of genes. A close relationship in global gene expression observed for adipocyte-like cells derived from muscle and adipocytes derived from intramuscular fat suggests a common origin for these cells. The role of transthyretin in myogenesis is a novel finding. Different genes were highly induced during the transdifferentiation of myogenic satellite cells and in the adipogenesis of preadipocytes, indicating the involvement of different molecular mechanisms in these processes. Induction of CD36 and FABP4 expression in adipocyte-like cells and adipocytes may share a common pathway.

Evaluation of High Resolution Magic-Angle Coil Spinning NMR Spectroscopy for Metabolic Profiling of Nanoliter Tissue Biopsies

High-resolution magic-angle sample spinning (HR-MAS) (1)H NMR spectroscopy of tissue biopsies combined with chemometric techniques has emerged as a valuable methodology for disease diagnosis and environmental assessments. However, the tissue mass required for such experiments is of the order of 10 mg, and this can compromise the metabolic evaluation because of tissue heterogeneity. Tissue availability is often a limitation for clinical studies due to histopathological requirements, which are currently the gold standard for diagnosis, for example, in the case of tumors. Here, we introduce the use of a rotating micro-NMR detector that optimizes the coil filling factor such that mass-limited samples can be measured. We show the results for measuring nanoliter volume tissue biopsies using a commercial HR-MAS probe for the first time. The method has been tested with bovine muscle and human gastric mucosal tumor tissue samples. The gain in mass sensitivity is approximate up to 17-fold, and the adequate spectral resolution (3 Hz) allows the measurement of the metabolite profiles in nanoliter volume samples, thereby limiting the ambiguity resulting from heterogeneous tissues; thus, the approach presents diagnostic potential for studies by metabonomics of mass-limited biopsies.

X‐Ray fluorescence as an assay tool for musculoskeletal nutrition animal research

XRF techniques are well established for the measurement of the presence of lead and heavy metals in osseous tissue. The advent of compact pyroelectric crystal x‐ray generators and silicon drift detectors presents a new opportunity for nutrition research that studies muscular, vascular and epithelial tissue. We compare the measurable ratios of Fe/K, Fe/Ca, and Fe/Cl in different bovine muscle tissues to establish a baseline feasibility study in preparation for in‐vivo measurements. The low power and portability characteristics of new technology XRF systems make it possible to examine epithelial tissue characteristics of animals in‐vivo. Limited initial calculations and models with backscattered x‐rays utilizing non‐imaging optics indicate promise. Non‐imaging optics are used to increase the effective collecting area of the spectral detection system in the backscatter configuration. We propose the concept that strategically selected ion ratios in muscle and vascular tissues can aid in quantifying “nutritional health” in laboratory animals. We acknowledge institutional support.

Technical note: Determination of cell-specific gene expression in bovine skeletal muscle tissue using laser microdissection and reverse-transcription quantitative polymerase chain reaction1

Skeletal muscle is a very heterogeneous tissue consisting of diverse cell types with specific transcription profiles. Therefore, the measured mRNA abundance of a certain cell type marker is influenced by the transcriptional activity as well as by the usually unknown number of contributing cells in the sample. In studies on the transcriptional activity of adipogenic genes, as indicators for the development of intramuscular adipocytes, an altered number of adipocytes or respective progenitor cells can mask changes in transcriptional activity. To overcome this problem, we started to use laser microdissection to isolate RNA of adipocytes and muscle fibers separately for downstream analysis. Even muscle fiber types can be collected and analyzed separately. Laser microdissection in combination with biopsy techniques enables gene expression studies of particular cell types during the life cycle of an animal. First experiences using laser microdissection for adipogenic gene expression studies in bovine skeletal muscle are described, and the influence of sample preparation and future challenges are discussed.

Dietary n‐3 Fatty Acids Significantly Suppress Lipogenesis in Bovine Muscle and Adipose Tissue: A Functional Genomics Approach

Changes in fatty acid composition of longissimus muscle and subcutaneous adipose tissue of German Holstein bulls induced by a grass-silage/n-3 fatty acid based intervention diet versus a maize-silage/n-6 fatty acid based control diet were analyzed and related to shifts in lipogenic gene expression, protein expression, and enzyme activity patterns. Significantly higher amounts of n-3 fatty acids and by mean factors of 2.2-2.5 decreased n-6/n-3 fatty acid ratios in both tissues were obtained upon n-3 fatty acid intervention. In longissimus muscle, these changes of fatty acid profiles were associated with reduced SREBP1c (p=0.02), ACC (p=0.00), FAS (p=0.10) and SCD (p=0.03) gene expression, Δ6D (p=0.03) and SCD (p=0.03) protein expression as well as SCD enzyme activity (p=0.03). In subcutaneous adipose tissue, significantly reduced ACC (p=0.00) and FAS (p=0.01) gene expression, SCD protein expression (p=0.02) and SCD enzyme activity (p=0.03) were detected upon n-3 fatty acid intervention, although lower degrees of correlation between gene and corresponding gene products were obtained in relation to longissimus muscle. The study elucidates tissue-specific functional genomic responses to dietary fatty acid manipulation in regard to fatty acid profile tailoring of animal tissues.

Procedures for Antibiotic Residues in Bovine Muscle Tissues

Acetonitrile extraction followed by primary-secondary amine dispersive SPE cleanup QuEChERS (quick, easy, cheap, effective, rugged, and safe), was compared to pressurized liquid extraction (PLE) using water at 70 degrees C for 10 min at 1500 psi for the determination of 16 veterinary drugs in bovine muscle tissues by LC/MS/MS. PLE was significantly more effective for the extraction of veterinary drugs (ranging from 69 to 103% with RSD < or = 18%) than QuEChERS (ranging from 19 to 89% with RSD < or = 19%). Linearity of the calibration curves was obtained over the range considered from 10 microg/kg or LOQ to 1000, microg/kg) with r2 > or = 0.99 for all the analytes by both methods. Although an internal standard was used, matrix effects were corrected using matrix- matched standards. LODs were from 5 to 30 microg/kg for PLE and from 10 to 100 microg/kg for QuEChERS. To establish and assess the most efficient conditions for each extraction method, statistical parametric and nonparametric tests were used. PLE with water almost eliminates the use or generation of hazardous wastes. The two methods were applied successfully in a routine analysis during surveys in 2008.

Liquid chromatography tandem mass spectrometry with ion trap and triple quadrupole analyzers for determination of thyreostatic drugs in urine and muscle tissue

Liquid chromatography tandem mass spectrometry methods were developed and validated to screen for and confirm residues of the thyreostatic drugs: tapazole, thiouracil, methylthiouracil, propylthiouracil, and phenylthiouracil in bovine and porcine urine and muscle tissues using dimethylthiouracil as internal standard. Thyreostats were extracted from urine samples with diethyl ether after derivatisation with 3-iodobenzylbromide in basic medium (pH 8.0) and analyzed by gradient elution on a Nucleosil C18 column with ion trap mass spectrometry detection using an electrospray source and triple quadrupole MS detection with turbo spray source. Thyreostats were extracted from muscle tissue with methanol, the denaturation of matrix protein was performed and then the same steps as for the urine samples were carried out. The methods were validated in accordance with the Commission Decision 2002/657/EC. Good thyreostats recoveries were obtained (from 82% to 117%) as well as acceptable within-lab reproducibility. The values of the decision limit CCα and the detection capability CCβ of five thyreostatic drugs are found to be below the recommended concentration set at 10 μg L −1 (kg −1). The results of the validation demonstrate that liquid chromatography mass spectrometry with ion trap detection does not meet the criteria for confirmation for some thyreostats and therefore was applied for screening purpose only.

Development of a biodegradable tissue adhesive based on functionalized 1,2-ethylene glycol bis(dilactic acid). II.

In body regions where damage and bleeding must be avoided, a substitute for mechanical tissue fixation by sutures or staplers is needed. Since tissue adhesives provide easy and fast handling they are a promising alternative. The present study reports the development and analysis of a tissue adhesive that consists of two adhesive components: hexamethylene diisocyanate (HDI) functionalized 1,2-ethylene glycol bis(dilactic acid) (ELA-NCO) and chitosan chloride. This composition was chosen based on preliminary studies on several chain elongation agents. The present study evaluates this adhesive system by IR-spectroscopy, tensile tests, and gel point measurements in comparison to fibrin glue. The system's in vitro biocompatibility was tested with mouse fibroblasts (L929) according to ISO 10993-5. Furthermore, an implantation study was performed in SPF-Wistar rats. The adhesive strength of manually applied mixtures or mixtures applied by double chamber syringes with a mixing extruder was determined to be significantly higher than that of fibrin glue on bovine muscle tissue at 37°C. Tensile strength increased further when exposure time of the adhesive was increased from 10 min to 48 h. The rheological gel point determination showed that the mixture of ELA-NCO/DMSO and chitosan chloride offers a time window large enough to readjust the fused joint during surgery, as opposed to fibrin glue. Additionally, the in vitro and in vivo biocompatibility studies of the adhesive system revealed no toxic effects on the surrounding tissue.

In Vivo Noninvasive Temperature Measurement by B-Mode Ultrasound Imaging

This study investigated the use of ultrasound image analysis in quantifying temperature changes in tissue, both ex vivo and in vivo, undergoing local hyperthermia. Temperature estimation is based on the thermal dependence of the acoustic speed in a heated medium. Because standard beam-forming algorithms on clinical ultrasound scanners assume a constant acoustic speed, temperature-induced changes in acoustic speed produce apparent scatterer displacements in B-mode images. A cross-correlation algorithm computes axial speckle pattern displacement in B-mode images of heated tissue, and a theoretically derived temperature-displacement relationship is used to generate maps of temperature changes within the tissue. Validation experiments were performed on excised tissue and in murine subjects, wherein low-intensity ultrasound was used to thermally treat tissue for several minutes. Diagnostic temperature estimation was performed using a linear array ultrasound transducer, while a fine-wire thermocouple invasively measured the temperature change. Pearson correlations ± SDs between the image-derived and thermocouple-measured temperature changes were R² = 0.923 ± 0.066 for 4 thermal treatments of excised bovine muscle tissue and R² = 0.917 ± 0.036 for 4 treatments of in vivo murine tumor tissue. The average differences between the two temperature measurements were 0.87°C ± 0.72°C for ex vivo studies and 0.97°C ± 0.55°C for in vivo studies. Maps of the temperature change distribution in tissue were generated for each experiment. This study demonstrates that velocimetric measurement on B-mode images has potential to assess temperature changes noninvasively in clinical applications.

GC/MS detection of central nervous tissues as specified BSE risk material in meat products: validation by an externally controlled blind trial

The addition of central nervous tissues (CNT), such as brain and spinal cord, in the manufacturing of meat products is either forbidden--if the material falls under the legal definition of specified risk material (SRM)--or must be labelled on the packed product. To foster official food control, several CNT detection methods were developed, but only fatty acid patterns as detected by gas chromatography/mass spectrometry (GC/MS) allow the further characterization of the detected CNT as to both the animal species and--surprisingly--the age of the animal from which the CNT was derived in accordance with the legal definition. Complementing a previous report in this journal by Lücker et al. 2010 (doi: 10.1007/s00216-010-3956-5) on CNT quantification by GC/MS, we now report results of the validation of this new analytical approach by an externally controlled blind trial elucidating its potential to identify the species and age of the CNT detected. The 72 samples (24 standards of emulsion-type sausage, each heated in three different batches: 75°C, 30 min; 115°C, 25 min; 133°C, 40 min) containing porcine, ovine or bovine muscle tissue and differing amounts of CNT (bovine or ovine brain: 0, 0.1, 0.5, 1.0, 3.0% m/m) were produced externally and provided blind for analyses to our laboratory. In accordance with the previous study, heating had no detectable effect on the GC/MS analysis. Judged by the present sensitivity of this method (cut-off 0.2% CNT), all of the samples containing 0.5% or more CNT (n = 57, 100%) were identified correctly as CNT-positive. The CNT species was identified correctly in 54 samples (94.7%), with three samples of one specific standard (0.5% ovine CNT) falsely classified as bovine CNT. However, the CNT age of these samples was correctly classified (more than 12 months). Overall, 57 samples (100%) were correctly classified as SRM-positive and 15 samples (100%) as SRM-negative. To the best of our knowledge, this is the first time that a legal demand for the (1) detection of traces of a specific tissue in a food matrix, (2) the identification of its taxonomic origin and (3) the classification of its age has been shown to be analytically possible in totally blind samples. The very positive validation results of this externally controlled blind trial recommend the present GC/MS approach for the detection of CNT in meat products as a reference method. However, our results also demonstrate the need for further studies, in particular to increase sensitivity and to conduct ring trials including more than one laboratory.

Tissue Dissolution by Sodium Hypochlorite: Effect of Concentration, Temperature, Agitation, and Surfactant

Aim Sodium hypochlorite is the most commonly used endodontic irrigant because of its antimicrobial and tissue-dissolving activity. The aim of this study was to evaluate and compare the effects of concentration, temperature, and agitation on the tissue-dissolving ability of sodium hypochlorite. In addition, a hypochlorite product with added surface active agent was compared with conventional hypochlorite solutions. Methods Three sodium hypochlorite solutions from two different manufacturers in concentrations of 1%, 2%, 4%, and 5.8% were tested at room temperature, 37°C, and 45°C with and without agitation by ultrasonic and sonic energy and pipetting. Distilled and sterilized tap water was used as controls. Pieces of bovine muscle tissue (68 ± 3 mg) were placed in 10 mL of each solution for five minutes. In selected samples, agitation was performed for one, two, or four 15-second periods per each minute. The tissue specimens were weighed before and after treatment, and the percentage of weight loss was calculated. The contact angle on dentin of the three solutions at concentrations of 1% and 5.8% was measured. Results Weight loss (dissolution) of the tissue increased almost linearly with the concentration of sodium hypochlorite. Higher temperatures and agitation considerably enhanced the efficacy of sodium hypochlorite. The effect of agitation on tissue dissolution was greater than that of temperature; continuous agitation resulted in the fastest tissue dissolution. Hypochlorite with added surface active agent had the lowest contact angle on dentin and was most effective in tissue dissolution in all experimental situations. Conclusions Optimizing the concentration, temperature, flow, and surface tension can improve the tissue-dissolving effectiveness of hypochlorite even 50-fold.

Buffer optimization for bovine Longissimus muscle tissues: Proteome analysis of Korean native cattle using 2-dimensional gel electrophoresis

Because beef contains a high proportion of marbling, we sought to optimize the solubilization of the longissimus muscle proteome using modified lysis and isoelectric focusing (IEF) rehydration buffers. Of the 3 lysis buffers tested, those containing a thiourea-urea mixture provided superior resolution, whereas that which contained only urea yielded consistently poor results. In addition, we found that the IEF rehydration buffer containing a thiourea-urea mixture, a high dithiothreitol level, and Pharmalyte was able to generate sharper 2-dimensional (2-D) gels, whereas that which contained immobilized pH gradient (IPG) buffer had no an effect on protein resolution. The number of different protein spots between the muscle-development stage (11 months) and the fat-development stage (17 months) in Hanwoo steers was 39, whereas the use of normal buffer resulted in a detection of a difference of only 7 protein spots. This study provides a methodological tool for studying the proteome of bovine longissimus muscle with a high fat content using 2-D gel electrophoresis (2-DE) gels.

Development of a biodegradable tissue adhesive based on functionalized 1,2‐ethylene glycol bis(dilactic acid). I.

Tissue adhesives are a valuable alternative for mechanical tissue fixation by sutures or staples. Adhesives are desirable in body regions where damage and bleeding must be avoided. Tissue adhesives provide easy and fast handling. This study reports the development of a tissue adhesive based on 1,2-ethylene glycol bis(dilactic acid) (ELA) functionalized with hexamethylene diisocyanate (HDI) to produce isocyanate terminated ELA-NCO which was characterized by NMR and FTIR spectroscopy. ELA-NCO together with chain elongation agents forms an adhesive system suitable for tissue fixation. Several biodegradable polymers, such as hyaluronic acid, gelatin, chitosan acetate, and chitosan chloride were tested as chain elongation agents to obtain an adhesive system and studied on bovine muscle tissue to evaluate their adhesive strength and compared to fibrin glue. Tensile strength of glued joints was determined by a Zwick universal testing machine at ambient temperature. Mixtures of ELA-NCO and chitosan acetate or chloride, showed significantly higher adhesive strength than fibrin glue. Reaction between ELA-NCO and chitosan chloride produced polyurethane was traced by FTIR spectroscopy. NMR, FTIR, and rheological measurements demonstrated that ELA-NCO and chitosan chloride can be sterilized by gamma-rays or superheated water vapor without alterations, respectively. A mixture of ELA-NCO and chitosan chloride can be useful as medical tissue adhesive.