Simple preparation of plant epidermal tissue for laser microdissection and downstream quantitative proteome and carbohydrate analysis

Directory of Open Access Journals (Sweden)

Christian eFalter

2015-03-01

Full Text Available The outwardly directed cell wall and associated plasma membrane of epidermal cells represent the first layers of plant defense against intruding pathogens. Cell wall modifications and the formation of defense structures at sites of attempted pathogen penetration are decisive for plant defense. A precise isolation of these stress-induced structures would allow a specific analysis of regulatory mechanism and cell wall adaption. However, methods for large-scale epidermal tissue preparation from the model plant Arabidopsis thaliana, which would allow proteome and cell wall analysis of complete, laser-microdissected epidermal defense structures, have not been provided. We developed the adhesive tape – liquid cover glass technique for simple leaf epidermis preparation from A. thaliana, which is also applicable on grass leaves. This method is compatible with subsequent staining techniques to visualize stress-related cell wall structures, which were precisely isolated from the epidermal tissue layer by laser microdissection coupled to laser pressure catapulting. We successfully demonstrated that these specific epidermal tissue samples could be used for quantitative downstream proteome and cell wall analysis. The development of the adhesive tape – liquid cover glass technique for simple leaf epidermis preparation and the compatibility to laser microdissection and downstream quantitative analysis opens new possibilities in the precise examination of stress- and pathogen-related cell wall structures in epidermal cells. Because the developed tissue processing is also applicable on A. thaliana, well-established, model pathosystems that include the interaction with powdery mildews can be studied to determine principal regulatory mechanisms in plant-microbe interaction with their potential outreach into crop breeding.

A Method for Preparing Spaceflight RNAlater-Fixed Arabidopsis thaliana (Brassicaceae Tissue for Scanning Electron Microscopy

Directory of Open Access Journals (Sweden)

Eric R. Schultz

2013-07-01

Full Text Available Premise of the study: In spaceflight experiments, tissues for morphologic study are fixed in 3% glutaraldehyde, while tissues for molecular study are fixed in RNAlater; thus, an experiment containing both study components requires multiple fixation strategies. The possibility of using RNAlater-fixed materials for standard SEM-based morphometric investigation was explored to expand the library of tissues available for analysis and maximize usage of samples returned from spaceflight, but these technologies have wide application to any situation where recovery of biological resources is limited. Methods and Results: RNAlater-fixed samples were desalinated in distilled water, dehydrated through graded methanol, plunged into liquid ethane, and transferred to cryovials for freeze-substitution. Sample tissues were critical point dried, mounted, sputter-coated, and imaged. Conclusions: The protocol resulted in acceptable SEM images from RNAlater-fixed Arabidopsis thaliana tissue. The majority of the tissues remained intact, including general morphology and finer details such as root hairs and trichomes.

A method for the determination of potassium concentration in organic tissue samples

International Nuclear Information System (INIS)

Maciel, A.C.A.

1976-12-01

An original method has been developed to detect small variations of potassium in several samples of organic tissue. These variations are relative to elements that are biologically representative, such as carbon, oxygen, and nitrogen. The samples are irradiated with a beam of protons from a Van de Graaff accelerator (4MV). Vacancies are created in the K-shell of potassium, and x-rays are emitted when these vacancies are filled with outer electrons. These X-rays and the protons elastically scattered by the nuclei of carbon, nitrogen and oxygen are detected and their energy spectra are analysed by computer programs especially elaborated for this purpose. A technique for routine preparation of samples in the laboratory was developed including the production of aluminum support layers, and the preparation of organic tissue samples with a low temperature microtome. The unique features of this method are that it does not destroy the tissue, permitting further analysis with the microscope, and the normalization of the amount of potassium using other elements (C,O,N) instead of the total mass of the sample. (Author) [pt

Cardiac tissue slices: preparation, handling, and successful optical mapping.

Science.gov (United States)

Wang, Ken; Lee, Peter; Mirams, Gary R; Sarathchandra, Padmini; Borg, Thomas K; Gavaghan, David J; Kohl, Peter; Bollensdorff, Christian

2015-05-01

Cardiac tissue slices are becoming increasingly popular as a model system for cardiac electrophysiology and pharmacology research and development. Here, we describe in detail the preparation, handling, and optical mapping of transmembrane potential and intracellular free calcium concentration transients (CaT) in ventricular tissue slices from guinea pigs and rabbits. Slices cut in the epicardium-tangential plane contained well-aligned in-slice myocardial cell strands ("fibers") in subepicardial and midmyocardial sections. Cut with a high-precision slow-advancing microtome at a thickness of 350 to 400 μm, tissue slices preserved essential action potential (AP) properties of the precutting Langendorff-perfused heart. We identified the need for a postcutting recovery period of 36 min (guinea pig) and 63 min (rabbit) to reach 97.5% of final steady-state values for AP duration (APD) (identified by exponential fitting). There was no significant difference between the postcutting recovery dynamics in slices obtained using 2,3-butanedione 2-monoxime or blebistatin as electromechanical uncouplers during the cutting process. A rapid increase in APD, seen after cutting, was caused by exposure to ice-cold solution during the slicing procedure, not by tissue injury, differences in uncouplers, or pH-buffers (bicarbonate; HEPES). To characterize intrinsic patterns of CaT, AP, and conduction, a combination of multipoint and field stimulation should be used to avoid misinterpretation based on source-sink effects. In summary, we describe in detail the preparation, mapping, and data analysis approaches for reproducible cardiac tissue slice-based investigations into AP and CaT dynamics. Copyright © 2015 the American Physiological Society.

Determination of protein carbonyls in plasma, cell extracts, tissue homogenates, isolated proteins: Focus on sample preparation and derivatization conditions.

Science.gov (United States)

Weber, Daniela; Davies, Michael J; Grune, Tilman

2015-08-01

Protein oxidation is involved in regulatory physiological events as well as in damage to tissues and is thought to play a key role in the pathophysiology of diseases and in the aging process. Protein-bound carbonyls represent a marker of global protein oxidation, as they are generated by multiple different reactive oxygen species in blood, tissues and cells. Sample preparation and stabilization are key steps in the accurate quantification of oxidation-related products and examination of physiological/pathological processes. This review therefore focuses on the sample preparation processes used in the most relevant methods to detect protein carbonyls after derivatization with 2,4-dinitrophenylhydrazine with an emphasis on measurement in plasma, cells, organ homogenates, isolated proteins and organelles. Sample preparation, derivatization conditions and protein handling are presented for the spectrophotometric and HPLC method as well as for immunoblotting and ELISA. An extensive overview covering these methods in previously published articles is given for researchers who plan to measure protein carbonyls in different samples. © 2015 Published by Elsevier Ltd.

Preparation of Laponite Bioceramics for Potential Bone Tissue Engineering Applications

Science.gov (United States)

Li, Kai; Ju, Yaping; Li, Jipeng; Zhang, Yongxing; Li, Jinhua; Liu, Xuanyong; Shi, Xiangyang; Zhao, Qinghua

2014-01-01

We report a facile approach to preparing laponite (LAP) bioceramics via sintering LAP powder compacts for bone tissue engineering applications. The sintering behavior and mechanical properties of LAP compacts under different temperatures, heating rates, and soaking times were investigated. We show that LAP bioceramic with a smooth and porous surface can be formed at 800°C with a heating rate of 5°C/h for 6 h under air. The formed LAP bioceramic was systematically characterized via different methods. Our results reveal that the LAP bioceramic possesses an excellent surface hydrophilicity and serum absorption capacity, and good cytocompatibility and hemocompatibility as demonstrated by resazurin reduction assay of rat mesenchymal stem cells (rMSCs) and hemolytic assay of pig red blood cells, respectively. The potential bone tissue engineering applicability of LAP bioceramic was explored by studying the surface mineralization behavior via soaking in simulated body fluid (SBF), as well as the surface cellular response of rMSCs. Our results suggest that LAP bioceramic is able to induce hydroxyapatite deposition on its surface when soaked in SBF and rMSCs can proliferate well on the LAP bioceramic surface. Most strikingly, alkaline phosphatase activity together with alizarin red staining results reveal that the produced LAP bioceramic is able to induce osteoblast differentiation of rMSCs in growth medium without any inducing factors. Finally, in vivo animal implantation, acute systemic toxicity test and hematoxylin and eosin (H&E)-staining data demonstrate that the prepared LAP bioceramic displays an excellent biosafety and is able to heal the bone defect. Findings from this study suggest that the developed LAP bioceramic holds a great promise for treating bone defects in bone tissue engineering. PMID:24955961

No-cost manual method for preparation of tissue microarrays having high quality comparable to semiautomated methods.

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Foda, Abd Al-Rahman Mohammad

2013-05-01

Manual tissue microarray (TMA) construction had been introduced to avoid the high cost of automated and semiautomated techniques. The cheapest and simplest technique for constructing manual TMA was that of using mechanical pencil tips. This study was carried out to modify this method, aiming to raise its quality to reach that of expensive ones. Some modifications were introduced to Shebl's technique. Two conventional mechanical pencil tips of different diameters were used to construct the recipient blocks. A source of mild heat was used, and blocks were incubated at 38°C overnight. With our modifications, 3 high-density TMA blocks were constructed. We successfully performed immunostaining without substantial tissue loss. Our modifications increased the number of cores per block and improved the stability of the cores within the paraffin block. This new, modified technique is a good alternative for expensive machines in many laboratories.

Method for preparing 99mTc-labelled radiopharmaceuticals for myocardial scintigraphy

International Nuclear Information System (INIS)

Seifert, S.; Syhre, R.; Muenze, R.

1987-01-01

Radiopharmaceuticals which preferably concentrate in myocardial tissue are prepared, in particular technetium compounds with the reducing ligand molecule DMPE. A method is introduced to convert pertechnetate in one step into the proposed compound by means of a saline, slow-oxidizing and lyophilized form of the reducing ligand DMPE, preferably DMPE x 2HCl

Comparison of tissue processing methods for microvascular visualization in axolotls.

Science.gov (United States)

Montoro, Rodrigo; Dickie, Renee

2017-01-01

The vascular system, the pipeline for oxygen and nutrient delivery to tissues, is essential for vertebrate development, growth, injury repair, and regeneration. With their capacity to regenerate entire appendages throughout their lifespan, axolotls are an unparalleled model for vertebrate regeneration, but they lack many of the molecular tools that facilitate vascular imaging in other animal models. The determination of vascular metrics requires high quality image data for the discrimination of vessels from background tissue. Quantification of the vasculature using perfused, cleared specimens is well-established in mammalian systems, but has not been widely employed in amphibians. The objective of this study was to optimize tissue preparation methods for the visualization of the microvascular network in axolotls, providing a basis for the quantification of regenerative angiogenesis. To accomplish this aim, we performed intracardiac perfusion of pigment-based contrast agents and evaluated aqueous and non-aqueous clearing techniques. The methods were verified by comparing the quality of the vascular images and the observable vascular density across treatment groups. Simple and inexpensive, these tissue processing techniques will be of use in studies assessing vascular growth and remodeling within the context of regeneration. Advantages of this method include: •Higher contrast of the vasculature within the 3D context of the surrounding tissue •Enhanced detection of microvasculature facilitating vascular quantification •Compatibility with other labeling techniques.

A novel semi-quantitative method for measuring tissue bleeding.

Science.gov (United States)

Vukcevic, G; Volarevic, V; Raicevic, S; Tanaskovic, I; Milicic, B; Vulovic, T; Arsenijevic, S

2014-03-01

In this study, we describe a new semi-quantitative method for measuring the extent of bleeding in pathohistological tissue samples. To test our novel method, we recruited 120 female patients in their first trimester of pregnancy and divided them into three groups of 40. Group I was the control group, in which no dilation was applied. Group II was an experimental group, in which dilation was performed using classical mechanical dilators. Group III was also an experimental group, in which dilation was performed using a hydraulic dilator. Tissue samples were taken from the patients' cervical canals using a Novak's probe via energetic single-step curettage prior to any dilation in Group I and after dilation in Groups II and III. After the tissue samples were prepared, light microscopy was used to obtain microphotographs at 100x magnification. The surfaces affected by bleeding were measured in the microphotographs using the Autodesk AutoCAD 2009 program and its "polylines" function. The lines were used to mark the area around the entire sample (marked A) and to create "polyline" areas around each bleeding area on the sample (marked B). The percentage of the total area affected by bleeding was calculated using the formula: N = Bt x 100 / At where N is the percentage (%) of the tissue sample surface affected by bleeding, At (A total) is the sum of the surfaces of all of the tissue samples and Bt (B total) is the sum of all the surfaces affected by bleeding in all of the tissue samples. This novel semi-quantitative method utilizes the Autodesk AutoCAD 2009 program, which is simple to use and widely available, thereby offering a new, objective and precise approach to estimate the extent of bleeding in tissue samples.

Preparation Methods for Improving PEEK’s Bioactivity for Orthopedic and Dental Application: A Review

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Davood Almasi

2016-01-01

Full Text Available There is an increased interest in the use of polyether ether ketone (PEEK for orthopedic and dental implant applications due to its elastic modulus close to that of bone, biocompatibility, and its radiolucent properties. However, PEEK is still categorized as bioinert due to its low integration with surrounding tissues. Many studies have reported on methods to increase the bioactivity of PEEK, but there is still one-preparation method for preparing bioactive PEEK implant where the produced implant with desirable mechanical and bioactivity properties is required. The aim of this review is to present the progress of the preparation methods for improvement of the bioactivity of PEEK and to discuss the strengths and weaknesses of the existing methods.

NEW METHOD FOR DETERMINATION OF ACTINIDES AND STRONTIUM IN ANIMAL TISSUE

Energy Technology Data Exchange (ETDEWEB)

Maxwell, S; Jay Hutchison, J; Don Faison, D

2007-05-07

The analysis of actinides in animal tissue samples is very important for environmental monitoring. There is a need to measure actinide isotopes with very low detection limits in animal tissue samples, including fish, deer, hogs, beef and shellfish. A new, rapid actinide separation method has been developed and implemented that allows the measurement of plutonium, neptunium, uranium, americium, curium and strontium isotopes in large animal tissue samples (100-200 g) with high chemical recoveries and effective removal of matrix interferences. This method uses stacked TEVA Resin{reg_sign}, TRU Resin{reg_sign} and DGA-Resin{reg_sign} cartridges from Eichrom Technologies (Darien, IL, USA) that allows the rapid separation of plutonium (Pu), neptunium (Np), uranium (U), americium (Am), and curium (Cm) using a single multi-stage column combined with alpha spectrometry. Sr-90 is collected on Sr Resin{reg_sign} from Eichrom Technologies (Darien, IL, USA). After acid digestion and furnace heating of the animal tissue samples, the actinides and Sr-89/90 are separated using column extraction chromatography. This method has been shown to be effective over a wide range of animal tissue matrices. By using vacuum box cartridge technology with rapid flow rates, sample preparation time is minimized.

Soft tissue tumors - imaging methods

International Nuclear Information System (INIS)

Arlart, I.P.

1985-01-01

Soft Tissue Tumors - Imaging Methods: Imaging methods play an important diagnostic role in soft tissue tumors concerning a preoperative evaluation of localization, size, topographic relationship, dignity, and metastatic disease. The present paper gives an overview about diagnostic methods available today such as ultrasound, thermography, roentgenographic plain films and xeroradiography, radionuclide methods, computed tomography, lymphography, angiography, and magnetic resonance imaging. Besides sonography particularly computed tomography has the most important diagnostic value in soft tissue tumors. The application of a recently developed method, the magnetic resonance imaging, cannot yet be assessed in its significance. (orig.) [de

Estimation of induced secondary metabolites in chickpea tissues in response to elicitor preparation of seaweeds

International Nuclear Information System (INIS)

Bi, F.; Iqbal, S.

2000-01-01

Disease response of plants in terms of induced browning and phytoalexin (induced secondary metabolites) production were recorded in the tissues of Cicer arietinum (Chick pea) treated with the High Molecular Crude Elicitor Preparations, HMWCEP 'Polysaccharides' of Hypnea musciformis (red algae), Padina tetrastromatica (brown algae) and Ulva lactulus (green algae). A UV-visible spectrophotometric method has been developed for the quantification of induced secondary metabolites with time. (author)

Simple and high yielding method for preparing tissue specific extracellular matrix coatings for cell culture.

Science.gov (United States)

DeQuach, Jessica A; Mezzano, Valeria; Miglani, Amar; Lange, Stephan; Keller, Gordon M; Sheikh, Farah; Christman, Karen L

2010-09-27

The native extracellular matrix (ECM) consists of a highly complex, tissue-specific network of proteins and polysaccharides, which help regulate many cellular functions. Despite the complex nature of the ECM, in vitro cell-based studies traditionally assess cell behavior on single ECM component substrates, which do not adequately mimic the in vivo extracellular milieu. We present a simple approach for developing naturally derived ECM coatings for cell culture that provide important tissue-specific cues unlike traditional cell culture coatings, thereby enabling the maturation of committed C2C12 skeletal myoblast progenitors and human embryonic stem cells differentiated into cardiomyocytes. Here we show that natural muscle-specific coatings can (i) be derived from decellularized, solubilized adult porcine muscle, (ii) contain a complex mixture of ECM components including polysaccharides, (iii) adsorb onto tissue culture plastic and (iv) promote cell maturation of committed muscle progenitor and stem cells. This versatile method can create tissue-specific ECM coatings, which offer a promising platform for cell culture to more closely mimic the mature in vivo ECM microenvironment.

Comparing culture and molecular methods for the identification of microorganisms involved in necrotizing soft tissue infections

DEFF Research Database (Denmark)

Rudkjøbing, Vibeke Børsholt; Thomsen, Trine Rolighed; Xu, Yijuan

2016-01-01

BACKGROUND: Necrotizing soft tissue infections (NSTIs) are a group of infections affecting all soft tissues. NSTI involves necrosis of the afflicted tissue and is potentially life threatening due to major and rapid destruction of tissue, which often leads to septic shock and organ failure. The gold...... to culture. Although the molecular methods generally gave concordant results, our results indicate that Microseq may misidentify or overlook microorganisms that can be detected by other molecular methods. Half of the patients were found to be infected with S. pyogenes, but several atypical findings were also...... that clinicians should be prepared to diagnose and treat any combination of microbial pathogens. Some of the tested molecular methods offer a faster turnaround time combined with a high specificity, which makes supplemental use of such methods attractive for identification of microorganisms, especially...

[DNA extraction from decomposed tissue by double-digest and magnetic beads methods].

Science.gov (United States)

Yang, Dian; Liu, Chao; Liu, Hong

2011-12-01

To study the effect of the double-digest and magnetic beads method for DNA extraction from 3 types of decomposed tissues. DNA of cartilages, nails and joint capsule in 91 highly decomposed corpses which had not been extracted by common magnetic beads method, were prepared with the double-digest and magnetic beads methods, and quantified with Quantifiler kit, followed by amplification with Sinofiler kit or Minifiler kit. DNA concentration extracted from the 91 highly decomposed cartilages, nails and joint capsule samples was 0-0.225 ng/microL. Sixty-two samples whose DNA concentration were more than 0.020 ng/microL had obtained 9 or more STR loci successfully. The detection rate was 68.13%. The successful rate of STR genotyping for the 3 types of decomposed tissues can be significantly improved by the double-digest and magnetic beads methods.

A novel method for sample preparation of fresh lung cancer tissue for proteomics analysis by tumor cell enrichment and removal of blood contaminants

Directory of Open Access Journals (Sweden)

Orre Lotta

2010-02-01

was an effective removal of contaminants from red blood cells and plasma proteins resulting in larger proteome coverage compared to the direct lysis of frozen samples. This sample preparation method may be successfully implemented for the discovery of lung cancer biomarkers on tissue samples using mass spectrometry-based proteomics.

Preparation and characterization of alginate microspheres for sustained protein delivery within tissue scaffolds

International Nuclear Information System (INIS)

Zhai Peng; Chen, X B; Schreyer, David J

2013-01-01

Tissue engineering scaffolds are designed not only to provide structural support for the repair of damaged tissue, but can also serve the function of bioactive protein delivery. Here we present a study on the preparation and characterization of protein-loaded microspheres, either alone or incorporated into mock tissue scaffolds, for sustained protein delivery. Alginate microspheres were prepared by a novel, small-scale water-in-oil emulsion technique and loaded with fluorescently labeled immunoglobulin G (IgG). Microsphere size appears to be influenced by the magnitude and distribution of force generated by mechanical stirring during emulsion. Protein release studies show that sustained IgG release from microspheres could be achieved and that application of a secondary coating of chitosan could further slow the rate of protein release. Preservation of bioactivity of released IgG protein was confirmed using an immunohistochemical assay. When IgG-loaded microspheres were incorporated into mock scaffolds, initial protein release was diminished and the overall time course of release was extended. The present study demonstrates that protein-loaded microspheres can be prepared with a controlled release profile and preserved biological activity, and can be incorporated into scaffolds to achieve sustained and prolonged protein delivery in a tissue engineering application. (paper)

An integrated sample preparation to determine coccidiostats and emerging Fusarium-mycotoxins in various poultry tissues with LC-MS/MS.

Science.gov (United States)

Jestoi, Marika; Rokka, Mervi; Peltonen, Kimmo

2007-05-01

The usefulness of an existing sample preparation technique used for ionophoric coccidiostats (lasalocid, monensin, salinomycin and narasin) was applied in the analysis of emerging Fusarium-mycotoxins beauvericin (BEA) and enniatins (ENNs) in poultry tissues (liver and meat). Also, maduramicin and liver as a new sample matrix was introduced. The developed methods were validated and applied for the determination of coccidiostats and BEA/ENNs in Finnish poultry tissues in 2004-2005. The validation parameters demonstrated that the integrated sample preparation technique is applicable to the parallel determination of these contaminants in poultry tissues. Of the samples analysed (276 meat and 43 liver), only trace levels of LAS, MON, SAL, NAR and MAD were detected in 7, 3, 5, 6 and 4% of the samples, respectively. Interestingly, for the first time, traces of BEA and ENNs could also be detected in animal tissues. BEA and ENNs A, A1, B and B1 were found in 2, 0.3, 0.6, 4 and 3% of the samples, respectively. The simultaneous presence of coccidiostats and mycotoxins was detected in three turkey samples in 2004.

A Filtration-based Method of Preparing High-quality Nuclei from Cross-linked Skeletal Muscle for Chromatin Immunoprecipitation.

Science.gov (United States)

Nohara, Kazunari; Chen, Zheng; Yoo, Seung-Hee

2017-07-06

Chromatin immunoprecipitation (ChIP) is a powerful method to determine protein binding to chromatin DNA. Fiber-rich skeletal muscle, however, has been a challenge for ChIP due to technical difficulty in isolation of high-quality nuclei with minimal contamination of myofibrils. Previous protocols have attempted to purify nuclei before cross-linking, which incurs the risk of altered DNA-protein interaction during the prolonged nuclei preparation process. In the current protocol, we first cross-linked the skeletal muscle tissue collected from mice, and the tissues were minced and sonicated. Since we found that ultracentrifugation was not able to separate nuclei from myofibrils using cross-linked muscle tissue, we devised a sequential filtration procedure to obtain high-quality nuclei devoid of significant myofibril contamination. We subsequently prepared chromatin by using an ultrasonicator, and ChIP assays with anti-BMAL1 antibody revealed robust circadian binding pattern of BMAL1 to target gene promoters. This filtration protocol constitutes an easily applicable method to isolate high-quality nuclei from cross-linked skeletal muscle tissue, allowing consistent sample processing for circadian and other time-sensitive studies. In combination with next-generation sequencing (NGS), our method can be deployed for various mechanistic and genomic studies focusing on skeletal muscle function.

Preparation of tissue samples for X-ray fluorescence microscopy

International Nuclear Information System (INIS)

Chwiej, Joanna; Szczerbowska-Boruchowska, Magdalena; Lankosz, Marek; Wojcik, Slawomir; Falkenberg, Gerald; Stegowski, Zdzislaw; Setkowicz, Zuzanna

2005-01-01

As is well-known, trace elements, especially metals, play an important role in the pathogenesis of many disorders. The topographic and quantitative elemental analysis of pathologically changed tissues may shed some new light on processes leading to the degeneration of cells in the case of selected diseases. An ideal and powerful tool for such purpose is the Synchrotron Microbeam X-ray Fluorescence technique. It enables the carrying out of investigations of the elemental composition of tissues even at the single cell level. The tissue samples for histopathological investigations are routinely fixed and embedded in paraffin. The authors try to verify the usefulness of such prepared tissue sections for elemental analysis with the use of X-ray fluorescence microscopy. Studies were performed on rat brain samples. Changes in elemental composition caused by fixation in formalin or paraformaldehyde and embedding in paraffin were examined. Measurements were carried out at the bending magnet beamline L of the Hamburger Synchrotronstrahlungslabor HASYLAB in Hamburg. The decrease in mass per unit area of K, Br and the increase in P, S, Fe, Cu and Zn in the tissue were observed as a result of the fixation. For the samples embedded in paraffin, a lower level of most elements was observed. Additionally, for these samples, changes in the composition of some elements were not uniform for different analyzed areas of rat brain

Preparation of tissue samples for X-ray fluorescence microscopy

Energy Technology Data Exchange (ETDEWEB)

Chwiej, Joanna [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland)]. E-mail: jchwiej@novell.ftj.agh.edu.pl; Szczerbowska-Boruchowska, Magdalena [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Lankosz, Marek [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Wojcik, Slawomir [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Falkenberg, Gerald [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron, Notkestr. 85, Hamburg (Germany); Stegowski, Zdzislaw [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Setkowicz, Zuzanna [Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Ingardena 6, 30-060 Cracow (Poland)

2005-12-15

As is well-known, trace elements, especially metals, play an important role in the pathogenesis of many disorders. The topographic and quantitative elemental analysis of pathologically changed tissues may shed some new light on processes leading to the degeneration of cells in the case of selected diseases. An ideal and powerful tool for such purpose is the Synchrotron Microbeam X-ray Fluorescence technique. It enables the carrying out of investigations of the elemental composition of tissues even at the single cell level. The tissue samples for histopathological investigations are routinely fixed and embedded in paraffin. The authors try to verify the usefulness of such prepared tissue sections for elemental analysis with the use of X-ray fluorescence microscopy. Studies were performed on rat brain samples. Changes in elemental composition caused by fixation in formalin or paraformaldehyde and embedding in paraffin were examined. Measurements were carried out at the bending magnet beamline L of the Hamburger Synchrotronstrahlungslabor HASYLAB in Hamburg. The decrease in mass per unit area of K, Br and the increase in P, S, Fe, Cu and Zn in the tissue were observed as a result of the fixation. For the samples embedded in paraffin, a lower level of most elements was observed. Additionally, for these samples, changes in the composition of some elements were not uniform for different analyzed areas of rat brain.

Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser

Directory of Open Access Journals (Sweden)

Beloica Miloš

2014-01-01

Full Text Available Goal of contemporary dentistry is to decrease the patient’s discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniques has led us to contemporary carbide tungsten and diamond borers that are used with obligatory water cooling. The innovation within this field represents newly developed polymer borers that can detect the difference between carious lesions and healthy tooth structure. In this way the cavity preparation may be performed without damaging dental healthy tissue. This is possible owing to their hardness which is lower than the hardness of intact dentin. Polymer borer preparation is painless with less vibration, while the increase in temperature is negligible. Lasers have been used in clinical dentistry since 1980s so it can be said that they represent a new technology. The function of lasers is based on ablation which requires water. Erbium lasers have shown the highest potential with their ability to produce effective ablation of hard dental tissues. Laser application in dentistry requires special training as well as some protective measures. Laser advantages, compared to traditional preparation techniques, involve the absence of vibration, painless preparation, possibility of preparation without anesthetic and easier patient’s adjustment to dental intervention which is of importance, especially in pediatric dentistry. [Projekat Ministarstva nauke Republike Srbije, br. 46009

Porous starch/cellulose nanofibers composite prepared by salt leaching technique for tissue engineering.

Science.gov (United States)

Nasri-Nasrabadi, Bijan; Mehrasa, Mohammad; Rafienia, Mohammad; Bonakdar, Shahin; Behzad, Tayebeh; Gavanji, Shahin

2014-08-08

Starch/cellulose nanofibers composites with proper porosity pore size, mechanical strength, and biodegradability for cartilage tissue engineering have been reported in this study. The porous thermoplastic starch-based composites were prepared by combining film casting, salt leaching, and freeze drying methods. The diameter of 70% nanofibers was in the range of 40-90 nm. All samples had interconnected porous morphology; however an increase in pore interconnectivity was observed when the sodium chloride ratio was increased in the salt leaching. Scaffolds with the total porogen content of 70 wt% exhibited adequate mechanical properties for cartilage tissue engineering applications. The water uptake ratio of nanocomposites was remarkably enhanced by adding 10% cellulose nanofibers. The scaffolds were partially destroyed due to low in vitro degradation rate after more than 20 weeks. Cultivation of isolated rabbit chondrocytes on the fabricated scaffold proved that the incorporation of nanofibers in starch structure improves cell attachment and proliferation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rapid column extraction method for actinides and strontium in fish and other animal tissue samples

International Nuclear Information System (INIS)

Maxwell III, S.L.; Faison, D.M.

2008-01-01

The analysis of actinides and radiostrontium in animal tissue samples is very important for environmental monitoring. There is a need to measure actinide isotopes and strontium with very low detection limits in animal tissue samples, including fish, deer, hogs, beef and shellfish. A new, rapid separation method has been developed that allows the measurement of plutonium, neptunium, uranium, americium, curium and strontium isotopes in large animal tissue samples (100-200 g) with high chemical recoveries and effective removal of matrix interferences. This method uses stacked TEVA Resin R , TRU Resin R and DGA Resin R cartridges from Eichrom Technologies (Darien, IL, USA) that allows the rapid separation of plutonium (Pu), neptunium (Np), uranium (U), americium (Am), and curium (Cm) using a single multi-stage column combined with alphaspectrometry. Strontium is collected on Sr Resin R from Eichrom Technologies (Darien, IL, USA). After acid digestion and furnace heating of the animal tissue samples, the actinides and 89/90 Sr are separated using column extraction chromatography. This method has been shown to be effective over a wide range of animal tissue matrices. Vacuum box cartridge technology with rapid flow rates is used to minimize sample preparation time. (author)

Effects of tissue-preparation-induced callose synthesis on estimates of plasmodesma size exclusion limits.

Science.gov (United States)

Radford, J E; White, R G

2001-01-01

Plasmodesmata are often characterised by their size exclusion limit (SEL), which is the molecular weight of the largest dye, introduced by microinjection, that will move from cell to cell. In this study, we investigated whether commonly used techniques for isolation and manipulation of tissues, and microinjection of fluorescent dyes, affected the SEL, and whether any such effects could be ameliorated by inhibiting callose deposition. We examined young root epidermal cells of Arabidopsis thaliana and staminal hair cells of Tradescantia virginiana, two tissues often used in experiments on symplastic transport. Transport in root tips dissected from the main plant body and in stamen hairs removed from the base of the stamen filament was compared with transport in undissected roots and stamen hairs attached to the base of the filament, respectively. Tissues were microinjected with fluorescent dyes (457 Da to > 3 kDa) with or without prior incubation in the callose deposition inhibitors 2-deoxy-D-glucose or aniline blue fluorochrome. In both tissues, dissection reduced the SEL, which was largely prevented by prior incubation in 2-deoxy-D-glucose but not by incubation in aniline blue fluorochrome. Thus, standard methods for tissue preparation can cause sufficient callose deposition to reduce cell-to-cell transport, and this needs to be considered in studies employing microinjection. Introduction of the dyes by pressure injection rather than iontophoresis decreased the SEL in A. thaliana but increased it in T. virginiana, showing that these two injection techniques do not necessarily give identical results and that plasmodesmata in different tissues may respond differently to similar experimental procedures.

A multi-scale controlled tissue engineering scaffold prepared by 3D printing and NFES technology

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Feifei Yan

2014-03-01

Full Text Available The current focus in the field of life science is the use of tissue engineering scaffolds to repair human organs, which has shown great potential in clinical applications. Extracellular matrix morphology and the performance and internal structure of natural organs are required to meet certain requirements. Therefore, integrating multiple processes can effectively overcome the limitations of the individual processes and can take into account the needs of scaffolds for the material, structure, mechanical properties and many other aspects. This study combined the biological 3D printing technology and the near-field electro-spinning (NFES process to prepare a multi-scale controlled tissue engineering scaffold. While using 3D printing technology to directly prepare the macro-scaffold, the compositing NFES process to build tissue micro-morphology ultimately formed a tissue engineering scaffold which has the specific extracellular matrix structure. This scaffold not only takes into account the material, structure, performance and many other requirements, but also focuses on resolving the controllability problems in macro- and micro-forming which further aim to induce cell directed differentiation, reproduction and, ultimately, the formation of target tissue organs. It has in-depth immeasurable significance to build ideal scaffolds and further promote the application of tissue engineering.

Acquiring molecular interference functions of X-ray coherent scattering for breast tissues by combination of simulation and experimental methods

International Nuclear Information System (INIS)

Chaparian, A.; Oghabian, M. A.; Changizi, V.

2009-01-01

Recently, it has been indicated that X-ray coherent scatter from biological tissues can be used to access signature of tissue. Some scientists are interested in studying this effect to get early detection of breast cancer. Since experimental methods for optimization are time consuming and expensive, some scientists suggest using simulation. Monte Carlo codes are the best option for radiation simulation: however, one permanent defect with Monte Carlo codes has been the lack of a sufficient physical model for coherent (Rayleigh) scattering, including molecular interference effects. Materials and Methods: It was decided to obtain molecular interference functions of coherent X-ray scattering for normal breast tissues by combination of modeling and experimental methods. A Monte Carlo simulation program was written to simulate the angular distribution of scattered photons for the normal breast tissue samples. Moreover, experimental diffraction patterns of these tissues were measured by means of energy dispersive X-ray diffraction method. The simulation and experimental data were used to obtain a tabulation of molecular interference functions for breast tissues. Results: With this study a tabulation of molecular interference functions for normal breast tissues Was prepared to facilitate the simulation diffraction patterns of the tissues without any experimental. Conclusion: The method may lead to design new systems for early detection of breast cancer.

Oromucosal film preparations: classification and characterization methods.

Science.gov (United States)

Preis, Maren; Woertz, Christina; Kleinebudde, Peter; Breitkreutz, Jörg

2013-09-01

Recently, the regulatory authorities have enlarged the variety of 'oromucosal preparations' by buccal films and orodispersible films. Various film preparations have entered the market and pharmacopoeias. Due to the novelty of the official monographs, no standardized characterization methods and quality specifications are included. This review reports the methods of choice to characterize oromucosal film preparations with respect to biorelevant characterization and quality control. Commonly used dissolution tests for other dosage forms are not transferable for films in all cases. Alternatives and guidance on decision, which methods are favorable for film preparations are discussed. Furthermore, issues about requirements for film dosage forms are reflected. Oromucosal film preparations offer a wide spectrum of opportunities. There are a lot of suggestions in the literature on how to control the quality of these innovative products, but no standardized tests are available. Regulatory authorities need to define the standards and quality requirements more precisely.

Use of Calcium and Alendronic Acid Preparations in Correction of Structural and Functional Disorders of Bone Tissue in Thyrotoxicosis

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O.B. Oliynyk

2012-02-01

Full Text Available Impact of calcium and alendronic acid preparations on disorders of structural and functional state of bone tissue in experimental animals at exogenic thyrotoxicosis was studied. It was defined that introduction of calcium preparations reduces bone mineral density loss in female rats with drug thyrotoxicosis, and combined use of calcium and alendronic acid prevents bone tissue loss regardless of thyrotoxicosis duration and presence of ovariectomy.

A Simple Preparation Method for Diphosphoimidazole

DEFF Research Database (Denmark)

Rosenberg, T.

1964-01-01

A simple method for the preparation of diphosphoimidazole is presented that involves direct phosphorylation of imidazole by phosphorus oxychloride in alkaline aqueous solution. Details are given on the use of diphosphoimidazole in preparing sodium phosphoramidate and certain phosphorylated amino...

Favorable Effects of the Detergent and Enzyme Extraction Method for Preparing Decellularized Bovine Pericardium Scaffold for Tissue Engineered Heart Valves

NARCIS (Netherlands)

Yang, Min; Chen, Chang-Zhi; Wang, Xue-Ning; Zhu, Ya-Bin; Gu, Y. John

2009-01-01

Bovine pericardium has been extensively applied as the biomaterial for artificial heart valves and may potentially be used as a scaffold for tissue-engineered heart valves after decellularization. Although various methods of decellularization are currently available, it is unknown which method is

Preparation methods of alginate nanoparticles

NARCIS (Netherlands)

Paques, J.P.; Linden, van der E.; Rijn, van C.J.M.; Sagis, L.M.C.

2014-01-01

This article reviews available methods for the formation of alginate nano-aggregates, nanocapsules and nanospheres. Primarily, alginate nanoparticles are being prepared by two methods. In the “complexation method”, complex formation on the interface of an oil droplet is used to form alginate

Preparation of hybrid biomaterials for bone tissue engineering

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Vilma Conceição Costa

2007-03-01

Full Text Available Tissue engineering has evolved from the use of biomaterials for bone substitution that fulfill the clinical demands of biocompatibility, biodegradability, non-immunogeneity, structural strength and porosity. Porous scaffolds have been developed in many forms and materials, but few reached the need of adequate physical, biological and mechanical properties. In the present paper we report the preparation of hybrid porous polyvinyl alcohol (PVA/bioactive glass through the sol-gel route, using partially and fully hydrolyzed polyvinyl alcohol, and perform structural characterization. Hybrids containing PVA and bioactive glass with composition 58SiO2-33CaO-9P2O5 were synthesized by foaming a mixture of polymer solution and bioactive glass sol-gel precursor solution. Sol-gel solution was prepared from mixing tetraethoxysilane (TEOS, triethylphosphate (TEP, and calcium chloride as chemical precursors. The hybrid composites obtained after aging and drying at low temperature were chemically and morphologically characterized through infrared spectroscopy and scanning electron microscopy. The degree of hydrolysis of PVA, concentration of PVA solution and different PVA-bioglass composition ratios affect the synthesis procedure. Synthesis parameters must be very well combined in order to allow foaming and gelation. The hybrid scaffolds obtained exhibited macroporous structure with pore size varying from 50 to 600 µm.

Comparison of a new hydro-surgical technique to traditional methods for the preparation of full-thickness skin grafts from canine cadaveric skin and report of a single clinical case.

Science.gov (United States)

Townsend, F I; Ralphs, S C; Coronado, G; Sweet, D C; Ward, J; Bloch, C P

2012-01-01

To compare the hydro-surgical technique to traditional techniques for removal of subcutaneous tissue in the preparation of full-thickness skin grafts. Ex vivo experimental study and a single clinical case report. Four canine cadavers and a single clinical case. Four sections of skin were harvested from the lateral flank of recently euthanatized dogs. Traditional preparation methods used included both a blade or scissors technique, each of which were compared to the hydro-surgical technique individually. Preparation methods were compared based on length of time for removal of the subcutaneous tissue from the graft, histologic grading, and measurable thickness as compared to an untreated sample. The hydro-surgical technique had the shortest skin graft preparation time as compared to traditional techniques (p = 0.002). There was no significant difference in the histological grading or measurable subcutaneous thickness between skin specimens. The hydro-surgical technique provides a rapid, effective debridement of subcutaneous tissue in the preparation of full-thickness skin grafts. There were not any significant changes in histological grade and subcutaneous tissue remaining among all treatment types. Additionally the hydro-surgical technique was successfully used to prepare a full-thickness meshed free skin graft in the reconstruction of a traumatic medial tarsal wound in a dog.

A Simple and Reproducible Method to Prepare Membrane Samples from Freshly Isolated Rat Brain Microvessels.

Science.gov (United States)

Brzica, Hrvoje; Abdullahi, Wazir; Reilly, Bianca G; Ronaldson, Patrick T

2018-05-07

The blood-brain barrier (BBB) is a dynamic barrier tissue that responds to various pathophysiological and pharmacological stimuli. Such changes resulting from these stimuli can greatly modulate drug delivery to the brain and, by extension, cause considerable challenges in the treatment of central nervous system (CNS) diseases. Many BBB changes that affect pharmacotherapy, involve proteins that are localized and expressed at the level of endothelial cells. Indeed, such knowledge on BBB physiology in health and disease has sparked considerable interest in the study of these membrane proteins. From a basic science research standpoint, this implies a requirement for a simple but robust and reproducible method for isolation of microvessels from brain tissue harvested from experimental animals. In order to prepare membrane samples from freshly isolated microvessels, it is essential that sample preparations be enriched in endothelial cells but limited in the presence of other cell types of the neurovascular unit (i.e., astrocytes, microglia, neurons, pericytes). An added benefit is the ability to prepare samples from individual animals in order to capture the true variability of protein expression in an experimental population. In this manuscript, details regarding a method that is utilized for isolation of rat brain microvessels and preparation of membrane samples are provided. Microvessel enrichment, from samples derived, is achieved by using four centrifugation steps where dextran is included in the sample buffer. This protocol can easily be adapted by other laboratories for their own specific applications. Samples generated from this protocol have been shown to yield robust experimental data from protein analysis experiments that can greatly aid the understanding of BBB responses to physiological, pathophysiological, and pharmacological stimuli.

Preparation of thermosensitive magnetic liposome encapsulated recombinant tissue plasminogen activator for targeted thrombolysis

Energy Technology Data Exchange (ETDEWEB)

Hsu, Hao-Lung [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Chen, Jyh-Ping, E-mail: jpchen@mail.cgu.edu.tw [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Department of Plastic and Reconstructive Surgery and Craniofacial Research Center, Chang Gung Memorial Hospital, Kwei-San, Taoyuan 33305, Taiwan, ROC (China); Graduate Institute of Health Industry and Technology, Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Department of Materials Engineering, Ming Chi University of Technology, Tai-Shan, New Taipei City 24301, Taiwan, ROC (China)

2017-04-01

Recombinant tissue plasminogen activator (rtPA) was encapsulated in thermosensitive magnetic liposome (TML) prepared from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, distearolyphosphatidyl ethanolamine-N-poly(ethylene glycol) 2000, cholesterol and Fe{sub 3}O{sub 4} magnetic nanoparticles by solvent evaporation/sonication and freeze-thaw cycles method. Response surface methodology was proved to be a powerful tool to predict the drug encapsulation efficiency and temperature-sensitive drug release. Validation experiments verified the accuracy of the model that provides a simple and effective method for fabricating TML with controllable encapsulation efficiency and predictable temperature-sensitive drug release behavior. The prepared samples were characterized for physico-chemical properties by dynamic light scattering, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. Temperature-sensitive release of rtPA could be confirmed from in vitro thrombolysis experiments. A thrombolytic drug delivery system using TML could be proposed for magnetic targeted delivery of rtPA to the site of thrombus followed by temperature-triggered controlled drug release in an alternating magnetic field. - Highlights: • rtPA and Fe{sub 3}O{sub 4} MNP were encapsulated in thermosensitive magnetic liposome (TML). • RSM could predict the drug encapsulation efficiency and temperature-sensitive drug release from TML. • Temperature-sensitive release of rtPA was confirmed from in vitro thrombolysis experiments. • TML-rtPA will be useful as a magnetic targeted nanodrug to improve clinical thrombolytic therapy.

Fast and Sensitive Method for Determination of Domoic Acid in Mussel Tissue

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Elena Barbaro

2016-01-01

Full Text Available Domoic acid (DA, a neurotoxic amino acid produced by diatoms, is the main cause of amnesic shellfish poisoning (ASP. In this work, we propose a very simple and fast analytical method to determine DA in mussel tissue. The method consists of two consecutive extractions and requires no purification steps, due to a reduction of the extraction of the interfering species and the application of very sensitive and selective HILIC-MS/MS method. The procedural method was validated through the estimation of trueness, extract yield, precision, detection, and quantification limits of analytical method. The sample preparation was also evaluated through qualitative and quantitative evaluations of the matrix effect. These evaluations were conducted both on the DA-free matrix spiked with known DA concentration and on the reference certified material (RCM. We developed a very selective LC-MS/MS method with a very low value of method detection limit (9 ng g−1 without cleanup steps.

Effect of sample preparation techniques on the concentrations and distributions of elements in biological tissues using µSRXRF: a comparative study

International Nuclear Information System (INIS)

Al-Ebraheem, A; Dao, E; Desouza, E; McNeill, F E; Farquharson, M J; Li, C; Wainman, B C

2015-01-01

Routine tissue sample preparation using chemical fixatives is known to preserve the morphology of the tissue being studied. A competitive method, cryofixation followed by freeze drying, involves no chemical agents and maintains the biological function of the tissue. The possible effects of both sample preparation techniques in terms of the distribution of bio-metals (calcium (Ca), copper (Cu) zinc (Zn), and iron (Fe) specifically) in human skin tissue samples was investigated. Micro synchrotron radiation x-ray fluorescence (μSRXRF) was used to map bio-metal distribution in epidermal and dermal layers of human skin samples from various locations of the body that have been prepared using both techniques. For Ca, Cu and Zn, there were statistically significant differences between the epidermis and dermis using the freeze drying technique (p = 0.02, p < 0.01, and p < 0.01, respectively). Also using the formalin fixed, paraffin embedded technique the levels of Ca, Cu and Zn, were significantly different between the epidermis and dermis layers (p = 0.03, p < 0.01, and p < 0.01, respectively). However, the difference in levels of Fe between the epidermis and dermis was unclear and further analysis was required. The epidermis was further divided into two sub-layers, one mainly composed of the stratum corneum and the other deeper layer, the stratum basale. It was found that the difference between the distribution of Fe in the two epidermal layers using the freeze drying technique resulted in a statistically significant difference (p = 0.012). This same region also showed a difference in Fe using the formalin fixed, paraffin embedded technique (p < 0.01). The formalin fixed, paraffin embedded technique also showed a difference between the deeper epidermal layer and the dermis (p < 0.01). It can be concluded that studies involving Ca, Cu and Zn might show similar results using both sample preparation techniques, however studies involving Fe would need more

Hamstrings tendon graft preparation for anterior cruciate ligament reconstruction using the WhipKnotTM soft tissue cinch technique.

Directory of Open Access Journals (Sweden)

Amin Masoumiganjgah

2012-04-01

Full Text Available BackgroundAppropriate graft tension and secure graft incorporation inbone tunnels are essential for successful anterior cruciateligament (ACL reconstruction using hamstrings tendonautografts. The WhipKnot™ soft tissue cinch, introduced bySmith and Nephew in 2004, is an alternative option to thecommonly used whipstitch technique during preparation ofthe hamstring autograft in ACL reconstruction.AimsTo investigate the effectiveness of the WhipKnot™ softtissue cinch and technique during the preparation of thetendon graft for ACL reconstruction.MethodA total of 33 ACL reconstruction operations performedbetween February 2011 and December 2011 were includedin this study. These were performed by a single seniorsurgeon who used the Whipknot™ technique for thepreparation of each graft. Four were used for eachoperation; two for each end of the harvested hamstringstendons, including semitendinosus and gracilis tendonsrespectively.ResultsIn total, 132 WhipKnots were used during the kneeoperations. Use of the WhipKnot™ technique resulted insuccessful graft preparations, tensioning and effective graftplacement in the tibial and femoral tunnels in almost allinstances. Only one case of WhipKnot™ failure (slippagewas recorded.ConclusionThese results indicate that the Whipknot™ technique is asafe, reliable and practical option for the preparation of thehamstrings autografts.

Final Report for X-ray Diffraction Sample Preparation Method Development

Energy Technology Data Exchange (ETDEWEB)

Ely, T. M. [Hanford Site (HNF), Richland, WA (United States); Meznarich, H. K. [Hanford Site (HNF), Richland, WA (United States); Valero, T. [Hanford Site (HNF), Richland, WA (United States)

2018-01-30

WRPS-1500790, “X-ray Diffraction Saltcake Sample Preparation Method Development Plan/Procedure,” was originally prepared with the intent of improving the specimen preparation methodology used to generate saltcake specimens suitable for XRD-based solid phase characterization. At the time that this test plan document was originally developed, packed powder in cavity supports with collodion binder was the established XRD specimen preparation method. An alternate specimen preparation method less vulnerable, if not completely invulnerable to preferred orientation effects, was desired as a replacement for the method.

Evaluation tissue dissolution property of 2.5 % Sodium Hypochlorite Prepared by Hydrochloric Acid and Sodium Bicarbonate: An in vitro

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Hamid Razavian

2016-08-01

Full Text Available Successful endodontic treatment requires chemical preparation in addition to mechanical preparation. The most common material for chemical preparations is sodium hypochlorite. One way to reduce the effects of pH adjustment is the use of sodium hypochlorite. The present paper was conducted to examine the effect of dilution with hydrochloric acid and sodium bicarbonate and reduce pH on ability of tissue solubility of sodium hypochlorite. The present study was conducted in vitro on bovine muscle tissue. Ability of tissue solubility was conducted in four groups respectively with active ingredient including 1 sodium hypochlorite diluted with distilled water 2 sodium hypochlorite diluted with sodium bicarbonate 3 sodium hypochlorite diluted with hydrochloric acid and finally 4 distilled water (control group. Each sample was firstly weighed and then placed in contact with 10 m/L solution for 60 minutes (five 12 -minute intervals. The sample was weighted every five minutes and solution was renewed. The results were analyzed using SPSS-21 Software based on variance analysis, Tukey and T-test (α=0.05. The findings showed that there was significant difference between first, second and third groups in terms of ability of tissue solubility. However, the tissue solubility in second and third groups was lower than first group and it was similar in second and third groups (P Value <0.001. Reduction of sodium bicarbonate PH using sodium hypochlorite and hydrochloric acid reduces ability of tissue solubility in sodium hypochlorite.

Preparation and Properties of 3D Printed Alginate–Chitosan Polyion Complex Hydrogels for Tissue Engineering

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Qiongqiong Liu

2018-06-01

Full Text Available Three-dimensional (3D printing holds great potential for preparing sophisticated scaffolds for tissue engineering. As a result of the shear thinning properties of an alginate solution, it is often used as 3D printing ink. However, it is difficult to prepare scaffolds with complexity structure and high fidelity, because the alginate solution has a low viscosity and alginate hydrogels prepared with Ca2+ crosslinking are mechanically weak. In this work, chitosan powders were dispersed and swelled in an alginate solution, which could effectively improve the viscosity of an alginate solution by 1.5–4 times. With the increase of chitosan content, the shape fidelity of the 3D printed alginate–chitosan polyion complex (AlCh PIC hydrogels were improved. Scanning electron microscope (SEM photographs showed that the lateral pore structure of 3D printed hydrogels was becoming more obvious. As a result of the increased reaction ion pairs in comparison to the alginate hydrogels that were prepared with Ca2+ crosslinking, AlCh PIC hydrogels were mechanically strong, and the compression stress of hydrogels at a 90% strain could achieve 1.4 MPa without breaking. In addition, human adipose derived stem cells (hASCs adhered to the 3D printed AlCh PIC hydrogels and proliferated with time, which indicated that the obtained hydrogels were biocompatible and could potentially be used as scaffolds for tissue engineering.

Protein-Based Nanoparticle Preparation via Nanoprecipitation Method

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Mohamad Tarhini

2018-03-01

Full Text Available Nanoparticles are nowadays largely investigated in the field of drug delivery. Among nanoparticles, protein-based particles are of paramount importance since they are natural, biodegradable, biocompatible, and nontoxic. There are several methods to prepare proteins containing nanoparticles, but only a few studies have been dedicated to the preparation of protein- based nanoparticles. Then, the aim of this work was to report on the preparation of bovine serum albumin (BSA-based nanoparticles using a well-defined nanoprecipitation process. Special attention has been dedicated to a systematic study in order to understand separately the effect of each operating parameter of the method (such as protein concentration, solvent/non-solvent volume ratio, non-solvent injection rate, ionic strength of the buffer solution, pH, and cross-linking on the colloidal properties of the obtained nanoparticles. In addition, the mixing processes (batch or drop-wise were also investigated. Using a well-defined formulation, submicron protein-based nanoparticles have been obtained. All prepared particles have been characterized in terms of size, size distribution, morphology, and electrokinetic properties. In addition, the stability of nanoparticles was investigated using Ultraviolet (UV scan and electrophoresis, and the optimal conditions for preparing BSA nanoparticles by the nanoprecipitation method were concluded.

Genetic evidence reveals improvement opportunities for tissue preparation in forensic analysis

OpenAIRE

Romero, Rosa Elena; Sandoval, Alejandro; Arango, Juliana; Camargo, Martha Lucia

2016-01-01

Introduction: Paraffin embedded tissues are an excellent alternative to obtain dna, especially when it is not possible to have fresh samples or when the tissue storage and preservation is not feasible; therefore, this sample is the only item available for matching purposes. The success in any genetic analysis implies having adequate tissue fixation and suitable dna extraction methods that allow to obtain good quality and quantity molecules, free of biological, chemical and microbiological con...

Preparation and Evaluation of Gelatin-Chitosan-Nanobioglass 3D Porous Scaffold for Bone Tissue Engineering

Directory of Open Access Journals (Sweden)

Kanchan Maji

2016-01-01

Full Text Available The aim of the present study was to prepare and characterize bioglass-natural biopolymer based composite scaffold and evaluate its bone regeneration ability. Bioactive glass nanoparticles (58S in the size range of 20–30 nm were synthesized using sol-gel method. Porous scaffolds with varying bioglass composition from 10 to 30 wt% in chitosan, gelatin matrix were fabricated using the method of freeze drying of its slurry at 40 wt% solids loading. Samples were cross-linked with glutaraldehyde to obtain interconnected porous 3D microstructure with improved mechanical strength. The prepared scaffolds exhibited >80% porosity with a mean pore size range between 100 and 300 microns. Scaffold containing 30 wt% bioglass (GCB 30 showed a maximum compressive strength of 2.2±0.1 MPa. Swelling and degradation studies showed that the scaffold had excellent properties of hydrophilicity and biodegradability. GCB 30 scaffold was shown to be noncytotoxic and supported mesenchymal stem cell attachment, proliferation, and differentiation as indicated by MTT assay and RUNX-2 expression. Higher cellular activity was observed in GCB 30 scaffold as compared to GCB 0 scaffold suggesting the fact that 58S bioglass nanoparticles addition into the scaffold promoted better cell adhesion, proliferation, and differentiation. Thus, the study showed that the developed composite scaffolds are potential candidates for regenerating damaged bone tissue.

Simple micellar electrokinetic chromatography method for the determination of hydrogen sulfide in hen tissues.

Science.gov (United States)

Kubalczyk, Paweł; Borowczyk, Kamila; Chwatko, Grażyna; Głowacki, Rafał

2015-04-01

A new method for the determination of hydrogen sulfide in hen tissues has been developed and validated. For estimation of hydrogen sulfide content, a sample (0.1 g) of hen tissue was treated according to the procedure consisted of some essential steps: simultaneous homogenization of a tissue and derivatization of hydrogen sulfide to its S-quinolinium derivative with 2-chloro-1-methylquinolinium tetrafluoroborate, separation of so-formed derivative by micellar electrokinetic chromatography with sweeping, and detection and quantitation with the use of UV detector set to measure analytical signals at 375 nm. Effective electrophoretic separation was achieved using fused silica capillary (effective length 41.5 cm, 75 μm id) and 0.05 mol/L, pH 8 phosphate buffer with the addition of 0.04 mol/L SDS and 26% ACN. The lower limit of quantification was 0.12 μmol hydrogen sulfide in 1 g of tissue. The calibration curve prepared in tissue homogenate for hydrogen sulfide showed linearity in the range from 0.15 to 2.0 μmol/g, with the coefficient of correlation 0.9978. The relative standard deviation of the points of the calibration curve varied from 8.3 to 3.2% RSD. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

"In situ preparation": new surgical procedure indicated for soft-tissue sarcoma of a lower limb in close proximity to major neurovascular structures.

Science.gov (United States)

Matsumoto, Seiichi; Kawaguchi, Noriyoshi; Manabe, Jun; Matsushita, Yasushi

2002-02-01

When soft-tissue sarcomas occur near neurovascular structures, preoperative images cannot always reveal the accurate relationship between the tumor and these structures. Therefore, in some patients, neurovascular structures are sacrificed unnecessarily. In other patients, neurovascular structures are preserved with an inappropriate margin, followed by local recurrence. The objective of this study was to evaluate a new surgical method, "in situ preparation" (ISP), which enables the preparation of neurovascular bundles and the intraoperative evaluation of the surgical margin without contamination by tumor cells. With this method, additional procedures, including pasteurization, alcohol soaking, and distilled water soaking of the preserved neurovascular bundle can also be performed to preserve the continuity of vessels. Between April 1992 and December 1998, 18 patients with soft-tissue sarcoma were operated on using ISP. The tumor and neurovascular structure were lifted en bloc from the surgical bed and separated from the field by the use of a vinyl sheet. The consistency of the neurovascular structures was preserved. The tissue block could be freely turned around and the neurovascular structure was separated from the block through the nearest approach. The margin between the tumor and neurovascular structure was evaluated, and an additional procedure, such as pasteurization, alcohol soaking or distilled water soaking, was performed, according to the safety of the surgical margin. Only one patient showed recurrence after ISP. Complications after ISP were arterial occlusion in two patients and nerve palsy in three patients. The main cause of these complications was the long period of pasteurization; modified additional procedures could prevent such complications. ISP is a useful method with which to ensure a safe surgical margin and good functional results.

Preparation of acellular scaffold for corneal tissue engineering by supercritical carbon dioxide extraction technology.

Science.gov (United States)

Huang, Yi-Hsun; Tseng, Fan-Wei; Chang, Wen-Hsin; Peng, I-Chen; Hsieh, Dar-Jen; Wu, Shu-Wei; Yeh, Ming-Long

2017-08-01

In this study, we developed a novel method using supercritical carbon dioxide (SCCO 2 ) to prepare acellular porcine cornea (APC). Under gentle extraction conditions using SCCO 2 technology, hematoxylin and eosin staining showed that cells were completely lysed, and cell debris, including nuclei, was efficiently removed from the porcine cornea. The SCCO 2 -treated corneas exhibited intact stromal structures and appropriate mechanical properties. Moreover, no immunological reactions and neovascularization were observed after lamellar keratoplasty in rabbits. All transplanted grafts and animals survived without complications. The transplanted APCs were opaque after the operation but became transparent within 2weeks. Complete re-epithelialization of the transplanted APCs was observed within 4weeks. In conclusion, APCs produced by SCCO 2 extraction technology could be an ideal and useful scaffold for corneal tissue engineering. We decellularized the porcine cornea using SCCO 2 extraction technology and investigated the characteristics, mechanical properties, and biocompatibility of the decellularized porcine cornea by lamellar keratoplasty in rabbits. To the best of our knowledge, this is the first report describing the use of SCCO 2 extraction technology for preparation of acellular corneal scaffold. We proved that the cellular components of porcine corneas had been efficiently removed, and the biomechanical properties of the scaffold were well preserved by SCCO 2 extraction technology. SCCO 2 -treated corneas maintained optical transparency and exhibited appropriate strength to withstand surgical procedures. In vivo, the transplanted corneas showed no evidence of immunological reactions and exhibited good biocompatibility and long-term stability. Our results suggested that the APCs developed by SCCO 2 extraction technology could be an ideal and useful scaffold for corneal replacement and corneal tissue engineering. Copyright © 2017 Acta Materialia Inc. Published by

Integration of gas chromatography mass spectrometry methods for differentiating ricin preparation methods.

Science.gov (United States)

Wunschel, David S; Melville, Angela M; Ehrhardt, Christopher J; Colburn, Heather A; Victry, Kristin D; Antolick, Kathryn C; Wahl, Jon H; Wahl, Karen L

2012-05-07

The investigation of crimes involving chemical or biological agents is infrequent, but presents unique analytical challenges. The protein toxin ricin is encountered more frequently than other agents and is found in the seeds of Ricinus communis, commonly known as the castor plant. Typically, the toxin is extracted from castor seeds utilizing a variety of different recipes that result in varying purity of the toxin. Moreover, these various purification steps can also leave or differentially remove a variety of exogenous and endogenous residual components with the toxin that may indicate the type and number of purification steps involved. We have applied three gas chromatography-mass spectrometry (GC-MS) based analytical methods to measure the variation in seed carbohydrates and castor oil ricinoleic acid, as well as the presence of solvents used for purification. These methods were applied to the same samples prepared using four previously identified toxin preparation methods, starting from four varieties of castor seeds. The individual data sets for seed carbohydrate profiles, ricinoleic acid, or acetone amount each provided information capable of differentiating different types of toxin preparations across seed types. However, the integration of the data sets using multivariate factor analysis provided a clear distinction of all samples based on the preparation method, independent of the seed source. In particular, the abundance of mannose, arabinose, fucose, ricinoleic acid, and acetone were shown to be important differentiating factors. These complementary tools provide a more confident determination of the method of toxin preparation than would be possible using a single analytical method.

Scalable robotic biofabrication of tissue spheroids

International Nuclear Information System (INIS)

Mehesz, A Nagy; Hajdu, Z; Visconti, R P; Markwald, R R; Mironov, V; Brown, J; Beaver, W; Da Silva, J V L

2011-01-01

Development of methods for scalable biofabrication of uniformly sized tissue spheroids is essential for tissue spheroid-based bioprinting of large size tissue and organ constructs. The most recent scalable technique for tissue spheroid fabrication employs a micromolded recessed template prepared in a non-adhesive hydrogel, wherein the cells loaded into the template self-assemble into tissue spheroids due to gravitational force. In this study, we present an improved version of this technique. A new mold was designed to enable generation of 61 microrecessions in each well of a 96-well plate. The microrecessions were seeded with cells using an EpMotion 5070 automated pipetting machine. After 48 h of incubation, tissue spheroids formed at the bottom of each microrecession. To assess the quality of constructs generated using this technology, 600 tissue spheroids made by this method were compared with 600 spheroids generated by the conventional hanging drop method. These analyses showed that tissue spheroids fabricated by the micromolded method are more uniform in diameter. Thus, use of micromolded recessions in a non-adhesive hydrogel, combined with automated cell seeding, is a reliable method for scalable robotic fabrication of uniform-sized tissue spheroids.

Scalable robotic biofabrication of tissue spheroids

Energy Technology Data Exchange (ETDEWEB)

Mehesz, A Nagy; Hajdu, Z; Visconti, R P; Markwald, R R; Mironov, V [Advanced Tissue Biofabrication Center, Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC (United States); Brown, J [Department of Mechanical Engineering, Clemson University, Clemson, SC (United States); Beaver, W [York Technical College, Rock Hill, SC (United States); Da Silva, J V L, E-mail: mironovv@musc.edu [Renato Archer Information Technology Center-CTI, Campinas (Brazil)

2011-06-15

Development of methods for scalable biofabrication of uniformly sized tissue spheroids is essential for tissue spheroid-based bioprinting of large size tissue and organ constructs. The most recent scalable technique for tissue spheroid fabrication employs a micromolded recessed template prepared in a non-adhesive hydrogel, wherein the cells loaded into the template self-assemble into tissue spheroids due to gravitational force. In this study, we present an improved version of this technique. A new mold was designed to enable generation of 61 microrecessions in each well of a 96-well plate. The microrecessions were seeded with cells using an EpMotion 5070 automated pipetting machine. After 48 h of incubation, tissue spheroids formed at the bottom of each microrecession. To assess the quality of constructs generated using this technology, 600 tissue spheroids made by this method were compared with 600 spheroids generated by the conventional hanging drop method. These analyses showed that tissue spheroids fabricated by the micromolded method are more uniform in diameter. Thus, use of micromolded recessions in a non-adhesive hydrogel, combined with automated cell seeding, is a reliable method for scalable robotic fabrication of uniform-sized tissue spheroids.

Sample preparation method for induced mutation on orchid

International Nuclear Information System (INIS)

Suhaimi Musa; Sakinah Ariffin

2005-01-01

Studies on the induction of mutation in Dendrobium orchid at MINT has produced a number of new orchid mutant cultivars. Tissue culture techniques on orchid seeds and meristem cloning are employed in preparing the samples for the mutation induction. Solid medium based on the Murashige and Skoog (1962) and liquid medium based on Vacin and Went (1949) were found to be suitable in producing protocorm like bodies (PLBs) that are required for the irradiation treatment. (Author)

Preparation of dexamethasone-loaded biphasic calcium phosphate nanoparticles/collagen porous composite scaffolds for bone tissue engineering.

Science.gov (United States)

Chen, Ying; Kawazoe, Naoki; Chen, Guoping

2018-02-01

Although bone is regenerative, its regeneration capacity is limited. For bone defects beyond a critical size, further intervention is required. As an attractive strategy, bone tissue engineering (bone TE) has been widely investigated to repair bone defects. However, the rapid and effective bone regeneration of large non-healing defects is still a great challenge. Multifunctional scaffolds having osteoinductivity and osteoconductivity are desirable to fasten functional bone tissue regeneration. In the present study, biomimetic composite scaffolds of collagen and biphasic calcium phosphate nanoparticles (BCP NPs) with a controlled release of dexamethasone (DEX) and the controlled pore structures were prepared for bone TE. DEX was introduced in the BCP NPs during preparation of the BCP NPs and hybridized with collagen scaffolds, which pore structures were controlled by using pre-prepared ice particulates as a porogen material. The composite scaffolds had well controlled and interconnected pore structures, high mechanical strength and a sustained release of DEX. The composite scaffolds showed good biocompatibility and promoted osteogenic differentiation of hMSCs when used for three-dimensional culture of human bone marrow-derived mesenchymal stem cells. Subcutaneous implantation of the composite scaffolds at the dorsa of athymic nude mice demonstrated that they facilitated the ectopic bone tissue regeneration. The results indicated the DEX-loaded BCP NPs/collagen composite scaffolds had high potential for bone TE. Scaffolds play a crucial role for regeneration of large bone defects. Biomimetic scaffolds having the same composition of natural bone and a controlled release of osteoinductive factors are desirable for promotion of bone regeneration. In this study, composite scaffolds of collagen and biphasic CaP nanoparticles (BCP NPs) with a controlled release nature of dexamethasone (DEX) were prepared and their porous structures were controlled by using ice particulates

Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Sharifi, Esmaeel; Azami, Mahmoud [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kajbafzadeh, Abdol-Mohammad [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Pediatric Urology Research Center, Section of Tissue Engineering and Stem Cells Therapy, Department of Pediatric Urology, Children' s Hospital Medical Center, Tehran, Iran (IRI) (Iran, Islamic Republic of); Moztarzadeh, Fatollah [Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of); Faridi-Majidi, Reza [Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Shamousi, Atefeh; Karimi, Roya [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ai, Jafar, E-mail: jafar_ai@tums.ac.ir [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Brain and Spinal Injury Research Center (BASIR), Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

2016-02-01

Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

International Nuclear Information System (INIS)

Sharifi, Esmaeel; Azami, Mahmoud; Kajbafzadeh, Abdol-Mohammad; Moztarzadeh, Fatollah; Faridi-Majidi, Reza; Shamousi, Atefeh; Karimi, Roya; Ai, Jafar

2016-01-01

Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

Sample preparation procedure for PIXE elemental analysis on soft tissues

International Nuclear Information System (INIS)

Kubica, B.; Kwiatek, W.M.; Dutkiewicz, E.M.; Lekka, M.

1997-01-01

Trace element analysis is one of the most important field in analytical chemistry. There are several instrumental techniques which are applied for determinations of microscopic elemental content. The PIXE (Proton Induced X-ray Emission) technique is one of the nuclear techniques that is commonly applied for such purpose due to its multielemental analysis possibilities. The aim of this study was to establish the optimal conditions for target preparation procedure. In this paper two different approaches to the topic are presented and widely discussed. The first approach was the traditional pellet technique and the second one was mineralization procedure. For the analysis soft tissue such as liver was used. Some results are also presented on water samples. (author)

Investigation of the “true” extraction recovery of analytes from multiple types of tissues and its impact on tissue bioanalysis using two model compounds

Energy Technology Data Exchange (ETDEWEB)

Yuan, Long, E-mail: long.yuan@bms.com [Bioanalytical Sciences, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Ma, Li [Biotransformation, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Dillon, Lisa [Discovery Toxicology, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Fancher, R. Marcus; Sun, Huadong [Metabolism and Pharmacokinetics, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Zhu, Mingshe [Biotransformation, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Lehman-McKeeman, Lois [Discovery Toxicology, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Aubry, Anne-Françoise [Bioanalytical Sciences, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States); Ji, Qin C., E-mail: qin.ji@bms.com [Bioanalytical Sciences, Research & Development, Bristol-Myers Squibb, Princeton, NJ 08543 (United States)

2016-11-16

LC-MS/MS has been widely applied to the quantitative analysis of tissue samples. However, one key remaining issue is that the extraction recovery of analyte from spiked tissue calibration standard and quality control samples (QCs) may not accurately represent the “true” recovery of analyte from incurred tissue samples. This may affect the accuracy of LC-MS/MS tissue bioanalysis. Here, we investigated whether the recovery determined using tissue QCs by LC-MS/MS can accurately represent the “true” recovery from incurred tissue samples using two model compounds: BMS-986104, a S1P{sub 1} receptor modulator drug candidate, and its phosphate metabolite, BMS-986104-P. We first developed a novel acid and surfactant assisted protein precipitation method for the extraction of BMS-986104 and BMS-986104-P from rat tissues, and determined their recoveries using tissue QCs by LC-MS/MS. We then used radioactive incurred samples from rats dosed with {sup 3}H-labeled BMS-986104 to determine the absolute total radioactivity recovery in six different tissues. The recoveries determined using tissue QCs and incurred samples matched with each other very well. The results demonstrated that, in this assay, tissue QCs accurately represented the incurred tissue samples to determine the “true” recovery, and LC-MS/MS assay was accurate for tissue bioanalysis. Another aspect we investigated is how the tissue QCs should be prepared to better represent the incurred tissue samples. We compared two different QC preparation methods (analyte spiked in tissue homogenates or in intact tissues) and demonstrated that the two methods had no significant difference when a good sample preparation was in place. The developed assay showed excellent accuracy and precision, and was successfully applied to the quantitative determination of BMS-986104 and BMS-986104-P in tissues in a rat toxicology study. - Highlights: • Investigated the “true” recovery in six different tissues using incurred

Investigation of the “true” extraction recovery of analytes from multiple types of tissues and its impact on tissue bioanalysis using two model compounds

International Nuclear Information System (INIS)

Yuan, Long; Ma, Li; Dillon, Lisa; Fancher, R. Marcus; Sun, Huadong; Zhu, Mingshe; Lehman-McKeeman, Lois; Aubry, Anne-Françoise; Ji, Qin C.

2016-01-01

LC-MS/MS has been widely applied to the quantitative analysis of tissue samples. However, one key remaining issue is that the extraction recovery of analyte from spiked tissue calibration standard and quality control samples (QCs) may not accurately represent the “true” recovery of analyte from incurred tissue samples. This may affect the accuracy of LC-MS/MS tissue bioanalysis. Here, we investigated whether the recovery determined using tissue QCs by LC-MS/MS can accurately represent the “true” recovery from incurred tissue samples using two model compounds: BMS-986104, a S1P 1 receptor modulator drug candidate, and its phosphate metabolite, BMS-986104-P. We first developed a novel acid and surfactant assisted protein precipitation method for the extraction of BMS-986104 and BMS-986104-P from rat tissues, and determined their recoveries using tissue QCs by LC-MS/MS. We then used radioactive incurred samples from rats dosed with 3 H-labeled BMS-986104 to determine the absolute total radioactivity recovery in six different tissues. The recoveries determined using tissue QCs and incurred samples matched with each other very well. The results demonstrated that, in this assay, tissue QCs accurately represented the incurred tissue samples to determine the “true” recovery, and LC-MS/MS assay was accurate for tissue bioanalysis. Another aspect we investigated is how the tissue QCs should be prepared to better represent the incurred tissue samples. We compared two different QC preparation methods (analyte spiked in tissue homogenates or in intact tissues) and demonstrated that the two methods had no significant difference when a good sample preparation was in place. The developed assay showed excellent accuracy and precision, and was successfully applied to the quantitative determination of BMS-986104 and BMS-986104-P in tissues in a rat toxicology study. - Highlights: • Investigated the “true” recovery in six different tissues using incurred tissue

Artificial urinary conduit construction using tissue engineering methods.

Science.gov (United States)

Kloskowski, Tomasz; Pokrywczyńska, Marta; Drewa, Tomasz

2015-01-01

Incontinent urinary diversion using an ileal conduit is the most popular method used by urologists after bladder cystectomy resulting from muscle invasive bladder cancer. The use of gastrointestinal tissue is related to a series of complications with the necessity of surgical procedure extension which increases the time of surgery. Regenerative medicine together with tissue engineering techniques gives hope for artificial urinary conduit construction de novo without affecting the ileum. In this review we analyzed history of urinary diversion together with current attempts in urinary conduit construction using tissue engineering methods. Based on literature and our own experience we presented future perspectives related to the artificial urinary conduit construction. A small number of papers in the field of tissue engineered urinary conduit construction indicates that this topic requires more attention. Three main factors can be distinguished to resolve this topic: proper scaffold construction along with proper regeneration of both the urothelium and smooth muscle layers. Artificial urinary conduit has a great chance to become the first commercially available product in urology constructed by regenerative medicine methods.

Hair cell counts in a rat model of sound damage: Effects of tissue preparation & identification of regions of hair cell loss.

Science.gov (United States)

Neal, Christopher; Kennon-McGill, Stefanie; Freemyer, Andrea; Shum, Axel; Staecker, Hinrich; Durham, Dianne

2015-10-01

Exposure to intense sound can damage or kill cochlear hair cells (HC). This loss of input typically manifests as noise induced hearing loss, but it can also be involved in the initiation of other auditory disorders such as tinnitus or hyperacusis. In this study we quantify changes in HC number following exposure to one of four sound damage paradigms. We exposed adult, anesthetized Long-Evans rats to a unilateral 16 kHz pure tone that varied in intensity (114 dB or 118 dB) and duration (1, 2, or 4 h) and sacrificed animals 2-4 weeks later. We compared two different methods of tissue preparation, plastic embedding/sectioning and whole mount dissection, for quantifying hair cell loss as a function of frequency. We found that the two methods of tissue preparation produced largely comparable cochleograms, with whole mount dissections allowing a more rapid evaluation of hair cell number. Both inner and outer hair cell loss was observed throughout the length of the cochlea irrespective of sound damage paradigm. Inner HC loss was either equal to or greater than outer HC loss. Increasing the duration of sound exposures resulted in more severe HC loss, which included all HC lesions observed in an analogous shorter duration exposure. Copyright © 2015 Elsevier B.V. All rights reserved.

Methods for preparation of deuterated amino acids

International Nuclear Information System (INIS)

Pshenichnikova, A.B.; Karnaukhova, E.N.; Zvonkova, E.N.

1995-01-01

The current state and prospects for the use of amino acids labeled with stable isotopes are considered. Methods for the preparation of deuterated amino acids, including synthetic, chemicoenzymatic, and biosynthetic ones, and deuterium exchange reactions are summarized. Problems in the preparation of optically pure amino acids are discussed. 120 refs., 15 figs

Method for preparation of superconductors

Energy Technology Data Exchange (ETDEWEB)

Barber, A.C.; McDougall, I.L.

1975-07-10

The invention deals with a method to prepare a superconductor consisting of a superconducting compound of at least two elements. It especially deals with superconductors which surround a superconducting intermetallic compounds of at least two elements, examples of which are Nb/sub 2/Sn and Nb/sub 3/Al.

An improved calcium chloride method preparation and ...

African Journals Online (AJOL)

Jane

2010-12-13

Dec 13, 2010 ... In this paper, we have reported a modified method for preparation and transformation of competent cells. This modified ... MATERIALS AND METHODS. Growth media ..... lipidic phase-transition temperature, and thus enhance.

A modified method for preparation of 123I-HDA

International Nuclear Information System (INIS)

Chen Fang; Decristoforo, C.; Staeger, A.; Fridrich, L.

1994-01-01

A modified method for preparation of 123 I-Heptadecanoic acid ( 123 I-HDA) is described. The labelling yield is 92.8%(n = 32, 85%-97%)by heating time of 15 minutes. The overall recovery is about 70%. The time for the whole preparation is about 90 min. The method described is reliable, and convenient. A carrier free and precursor free product of high purity can be prepared in a reasonable short time

Preparation and evaluation of enrofloxacin microspheres and tissue distribution in rats.

Science.gov (United States)

Yang, Fan; Kang, Jijun; Yang, Fang; Zhao, Zhensheng; Kong, Tao; Zeng, Zhenling

2015-01-01

New enrofloxacin microspheres were formulated, and their physical properties, lung-targeting ability, and tissue distribution in rats were examined. The microspheres had a regular and round shape. The mean diameter was 10.06 µm, and the diameter of 89.93% of all microspheres ranged from 7.0 µm to 30.0 µm. Tissue distribution of the microspheres was evaluated along with a conventional enrofloxacin preparation after a single intravenous injection (7.5 mg of enrofloxacin/kg bw). The results showed that the elimination half-life (t1/2β) of enrofloxacin from lung was prolonged from 7.94 h for the conventional enrofloxacin to 13.28 h for the microspheres. Area under the lung concentration versus time curve from 0 h to ∞ (AUC00∞) was increased from 11.66 h·µg/g to 508.00 h·µg/g. The peak concentration (Cmax) in lung was increased from 5.95 µg/g to 93.36 µg/g. Three lung-targeting parameters were further assessed and showed that the microspheres had remarkable lung-targeting capabilities.

State-of-the-Art Methods for Brain Tissue Segmentation: A Review.

Science.gov (United States)

Dora, Lingraj; Agrawal, Sanjay; Panda, Rutuparna; Abraham, Ajith

2017-01-01

Brain tissue segmentation is one of the most sought after research areas in medical image processing. It provides detailed quantitative brain analysis for accurate disease diagnosis, detection, and classification of abnormalities. It plays an essential role in discriminating healthy tissues from lesion tissues. Therefore, accurate disease diagnosis and treatment planning depend merely on the performance of the segmentation method used. In this review, we have studied the recent advances in brain tissue segmentation methods and their state-of-the-art in neuroscience research. The review also highlights the major challenges faced during tissue segmentation of the brain. An effective comparison is made among state-of-the-art brain tissue segmentation methods. Moreover, a study of some of the validation measures to evaluate different segmentation methods is also discussed. The brain tissue segmentation, content in terms of methodologies, and experiments presented in this review are encouraging enough to attract researchers working in this field.

Innovative methods for inorganic sample preparation

Energy Technology Data Exchange (ETDEWEB)

Essling, A.M.; Huff, E.A.; Graczyk, D.G.

1992-04-01

Procedures and guidelines are given for the dissolution of a variety of selected materials using fusion, microwave, and Parr bomb techniques. These materials include germanium glass, corium-concrete mixtures, and zeolites. Emphasis is placed on sample-preparation approaches that produce a single master solution suitable for complete multielement characterization of the sample. In addition, data are presented on the soil microwave digestion method approved by the Environmental Protection Agency (EPA). Advantages and disadvantages of each sample-preparation technique are summarized.

Innovative methods for inorganic sample preparation

International Nuclear Information System (INIS)

Essling, A.M.; Huff, E.A.; Graczyk, D.G.

1992-04-01

Procedures and guidelines are given for the dissolution of a variety of selected materials using fusion, microwave, and Parr bomb techniques. These materials include germanium glass, corium-concrete mixtures, and zeolites. Emphasis is placed on sample-preparation approaches that produce a single master solution suitable for complete multielement characterization of the sample. In addition, data are presented on the soil microwave digestion method approved by the Environmental Protection Agency (EPA). Advantages and disadvantages of each sample-preparation technique are summarized

Preparation and properties of polyvinyl alcohol (PVA) and hydroxylapatite (HA) hydrogels for cartilage tissue engineering.

Science.gov (United States)

Yuan, F; Ma, M; Lu, L; Pan, Z; Zhou, W; Cai, J; Luo, S; Zeng, W; Yin, F

2017-05-20

A novel bioactive hydrogel for cartilage tissue based on polyvinyl alcohol (PVA) and hydroxylapatite (HA) were prepared, the effects of its component contents on the mechanical properties and microstructure of the hydrogel were investigated. The important properties of the scaffold composites, such as density, porosity, compressive modulus and microstructure were studied and analyzed through various measurements and methods. The biodegradability of hydrogel was evaluated by soaking the samples into artificial degradation solution at body temperature (36 - 37 oC) in vitro. Experimental results showed that the PVA/HA hydrogels had a density of 0.572 - 0.683 g/cm3, a porosity of 63.25 - 96.14% and a compressive modulus of 5.62 - 8.24 MP. The HA compound in the hydrogels enhanced the biodegradation significantly and linearly increased the rate of biodegradation by 2.3 - 8.5 %. The compressive modulus of PVA/HA exhibited a linear reduce to 0.86 - 1.53 MP with the time of degradation. The scaffold composites PVA/HA possess a high porosity, decent compressive modulus and good biodegradability. After further optimizing the structure and properties, this composite might be considered as novel hydrogel biomaterials to be applied in the field of cartilage tissue engineering.

Comparison of two methods of preparation of tissue to study the internal anatomy of the delphacid Togosodes orizicolus with microscopy of electronic light

International Nuclear Information System (INIS)

Macaya-Lizano, A.V.; Pereira, R.; Espinoza, A.M.

1997-01-01

Two methods of embedding, sectioning and staining were developed to study the internal anatomy of delphacid plant hopper Tagosodes orizicolus, one of the most important plagues of rice in Latin America and the only vector of the white leaf tenuivirus (RHBV), using both light and electron microscopy. The paraffines-hematoxyline-eosin Y method allows color identification of tissues, for example purple for fat tissue, pink for muscles, yellow-brown for exocutile, while the resin-toluidine-blue method preserves better the ultrastructure but do not permit color identification. The information obtained by these procedures is complementary and the material can also be used for in situ studies by immuno microscopy, to assess the changes in cell ultrastructure and the localization and replication of the RHBV during its infection cycle in the insect vector. (author) [es

Growing tissues in real and simulated microgravity: new methods for tissue engineering.

Science.gov (United States)

Grimm, Daniela; Wehland, Markus; Pietsch, Jessica; Aleshcheva, Ganna; Wise, Petra; van Loon, Jack; Ulbrich, Claudia; Magnusson, Nils E; Infanger, Manfred; Bauer, Johann

2014-12-01

Tissue engineering in simulated (s-) and real microgravity (r-μg) is currently a topic in Space medicine contributing to biomedical sciences and their applications on Earth. The principal aim of this review is to highlight the advances and accomplishments in the field of tissue engineering that could be achieved by culturing cells in Space or by devices created to simulate microgravity on Earth. Understanding the biology of three-dimensional (3D) multicellular structures is very important for a more complete appreciation of in vivo tissue function and advancing in vitro tissue engineering efforts. Various cells exposed to r-μg in Space or to s-μg created by a random positioning machine, a 2D-clinostat, or a rotating wall vessel bioreactor grew in the form of 3D tissues. Hence, these methods represent a new strategy for tissue engineering of a variety of tissues, such as regenerated cartilage, artificial vessel constructs, and other organ tissues as well as multicellular cancer spheroids. These aggregates are used to study molecular mechanisms involved in angiogenesis, cancer development, and biology and for pharmacological testing of, for example, chemotherapeutic drugs or inhibitors of neoangiogenesis. Moreover, they are useful for studying multicellular responses in toxicology and radiation biology, or for performing coculture experiments. The future will show whether these tissue-engineered constructs can be used for medical transplantations. Unveiling the mechanisms of microgravity-dependent molecular and cellular changes is an up-to-date requirement for improving Space medicine and developing new treatment strategies that can be translated to in vivo models while reducing the use of laboratory animals.

THE PLACE OF RETRACTION CORDS AMONG THE TISSUE DISPLACEMENT METHODS

Directory of Open Access Journals (Sweden)

Stoyan Yankov

2017-12-01

Full Text Available Gingival displacement is performed to create sufficient space between the finishing line and the gingival tissue, to allow the injection of the adequate bulk of the impression material into the expanded crevice. Control of moisture in the sulcus is also necessary. The variety of methods for tissue management can be broadly classified into surgical and non-surgical. Objective: To analyse the properties of tissue displacement methods, described in the literature for the last 4 years and display the prefered choices of the practitioners. Material and method: A time range from the last 4 years was set. Using the keywords “retraction cord” and “survey,” we found 64 from 115 articles in total, relevant to our topic. Patents, citations and books weren’t included in this review. Results from the overview of the properties of the different tissue management methods indicate that retraction cords take a significant place among them and can be recognised as a classical and well known method. Conclusions: The studies from the articles show adequate sulcal width right after retraction with most methods, sufficient haemostasis can also be obtained. Every each method, however, is accompanied by several drawbacks. Concidering all the quallities of the different tissue dispalcent methods, there is no specific evidence to promote the use of a single technique over any other. The selection of the method for gingival retraction primarily depends on each clinical case. However, the retraction cord technique remains to be the prefered method for gingival management due to its many advantages.

How-To-Do-It: Using Cauliflower to Demonstrate Plant Tissue Culture.

Science.gov (United States)

Haldeman, Janice H.; Ellis, Jane P.

1988-01-01

Presents techniques used for disinfestation of plant material, preparation of equipment and media, and laboratory procedures for tissue culture using cauliflower. Details methods for preparing solutions and plant propagation by cloning. (CW)

Preparation of degradable porous structures based on 1,3-trimethylene carbonate and D,L-lactide (co)polymers for heart tissue engineering

NARCIS (Netherlands)

Pego, AP; Siebum, B; Van Luyn, MJA; Van Seijen, XJGY; Poot, AA; Grijpma, DW; Feijen, J

2003-01-01

Biodegradable porous scaffolds for heart tissue engineering were prepared from amorphous elastomeric (co)polymers of 1,3-trimethylene carbonate (TMC) and D,L-lactide (DLLA). Leaching of salt from compression-molded polymer-salt composites allowed the preparation of highly porous structures in a

Influences of different sample preparation methods on tooth enamel ESR signals

International Nuclear Information System (INIS)

Zhang Wenyi; Jiao Ling; Zhang Liang'an; Pan Zhihong; Zeng Hongyu

2005-01-01

Objective: To study the influences of different sample preparation methods on tooth enamel ESR signals in order to reduce the effect of dentine on their sensitivities to radiation. Methods: The enamel was separated from dentine of non-irradiated adult teeth by mechanical, chemical, or both methods. The samples of different preparations were scanned by an ESR spectrometer before and after irradiation. Results: The response of ESR signals of samples prepared with different methods to radiation dose was significantly different. Conclusion: The selection of sample preparation method is very important for dose reconstruction by tooth enamel ESR dosimetry, especially in the low dose range. (authors)

Method for Processing Liver Spheroids Using an Automatic Tissue Processor

Science.gov (United States)

2016-05-01

alcohol dehydration and hot liquid wax infiltration. After the water in the tissue is replaced with wax and cooled, it then becomes possible to cut...effective for processing and preparing microscopy slides of liver spheroids. The general process involved formalin fixation, dehydration in a...DPBS);  formalin (37% neutral buffer formaldehyde);  series of alcohol solutions: 70, 80, 95, and 100% ethanol in water; 2  xylene

Changing perspective on tissue processing - comparison of microwave histoprocessing method with the conventional method

Directory of Open Access Journals (Sweden)

G Shrestha

2015-09-01

Full Text Available Background: Histopathological examination of tissues requires sliver of formalin fixed tissue that has been chemically processed and then stained with Haematoxylin and Eosin. The time honored conventional method of tissue processing, which requires 12 to 13 hours for completion, is employed at majority of laboratories but is now seeing the

Preparation and Characterization of Soluble Eggshell Membrane Protein/PLGA Electro spun Nano fibers for Guided Tissue Regeneration Membrane

International Nuclear Information System (INIS)

Jia, J.; Liu, G.; Duan, Y.; Guo, Z.; Yu, J.

2012-01-01

Guided tissue regeneration (GTR) is a widely used method in periodontal therapy, which involves the placement of a barrier membrane to exclude migration of epithelium and ensure repopulation of periodontal ligament cells. The objective of this study is to prepare and evaluate a new type of soluble eggshell membrane protein (SEP)/poly (lactic-co-glycolic acid) (PLGA) nano fibers using electro spinning method for GTR membrane application. SEP/PLGA nano fibers were successfully prepared with various blending ratios. The morphology, chemical composition, surface wettability, and mechanical properties of the nano fibers were characterized using scanning electron microscopy (SEM), contact angle measurement, Fourier transform-infrared spectroscopy (FTIR), and a universal testing machine. L-929 fibroblast cells were used to evaluate the biocompatibility of SEP/PLGA nano fibers and investigate the interaction between cells and nano fibers. Results showed that the SEP/PLGA electro spun membrane was composed of uniform, bead-free nano fibers, which formed an interconnected porous network structure. Mechanical property of SEP has been greatly improved by the addition of PLGA. The biological study results showed that SEP/PLGA nano fibers could enhance cell attachment, spreading, and proliferation. The study indicated the potential of SEP/PLGA nano fibers for GTR application and provided a basis for future optimization

A novel method for the preparation of electrophoretic display microcapsules

Energy Technology Data Exchange (ETDEWEB)

Liu, Xiao-Meng; He, Jing; Liu, Sheng-Yun [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Chen, Jian-Feng [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Le, Yuan, E-mail: leyuan@mail.buct.edu.cn [State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China)

2014-07-01

Highlights: • The electrophoretic display microcapsules were prepared by coaxial jet method aided by gas spray. • The positions of inner tube, liquid and gas flow rate of the process were investigated. • The size and shell thickness of the prepared microcapsules were controllable. • The prepared microcapsules had high coating ratio and exhibit reversible response to DC field. - Abstract: The narrow distributed electrophoretic display microcapsules containing electrophoretic ink were prepared using coaxial jet method aided by gas spray. Experimental results showed the size and shell thickness of the microcapsules could be controlled by adjusting flow rates of core and shell fluids as well as gas. The as-prepared white and red microcapsules, with average size of 100 and 200 μm respectively, had high coating ratio (above 90%) and exhibited reversible response to DC electric field. Compared with the approach of other microencapsulation methods, the new technique not only has a simple procedure but also provides a more effective way of size control. This novel method is expected to prepare microcapsules with potential application in the fields of electronic paper and other material science.

Clinical tooth preparations and associated measuring methods: a systematic review.

Science.gov (United States)

Tiu, Janine; Al-Amleh, Basil; Waddell, J Neil; Duncan, Warwick J

2015-03-01

The geometries of tooth preparations are important features that aid in the retention and resistance of cemented complete crowns. The clinically relevant values and the methods used to measure these are not clear. The purpose of this systematic review was to retrieve, organize, and critically appraise studies measuring clinical tooth preparation parameters, specifically the methodology used to measure the preparation geometry. A database search was performed in Scopus, PubMed, and ScienceDirect with an additional hand search on December 5, 2013. The articles were screened for inclusion and exclusion criteria and information regarding the total occlusal convergence (TOC) angle, margin design, and associated measuring methods were extracted. The values and associated measuring methods were tabulated. A total of 1006 publications were initially retrieved. After removing duplicates and filtering by using exclusion and inclusion criteria, 983 articles were excluded. Twenty-three articles reported clinical tooth preparation values. Twenty articles reported the TOC, 4 articles reported margin designs, 4 articles reported margin angles, and 3 articles reported the abutment height of preparations. A variety of methods were used to measure these parameters. TOC values seem to be the most important preparation parameter. Recommended TOC values have increased over the past 4 decades from an unachievable 2- to 5-degree taper to a more realistic 10 to 22 degrees. Recommended values are more likely to be achieved under experimental conditions if crown preparations are performed outside of the mouth. We recommend that a standardized measurement method based on the cross sections of crown preparations and standardized reporting be developed for future studies analyzing preparation geometry. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Porous PEOT/PBT scaffolds for bone tissue engineering: preparation, characterization, and in vitro bone marrow cell culturing

NARCIS (Netherlands)

Claase, M.B.; Grijpma, Dirk W.; Mendes, S.C.; Mendes, Sandra C.; de Bruijn, Joost Dick; Feijen, Jan

2003-01-01

The preparation, characterization, and in vitro bone marrow cell culturing on porous PEOT/PBT copolymer scaffolds are described. These scaffolds are meant for use in bone tissue engineering. Previous research has shown that PEOT/PBT copolymers showed in vivo degradation, calcification, and bone

Comparing different preparation methods to study human fibrin fibers and platelets using TEM.

Science.gov (United States)

Buys, Antoinette V; Pretorius, Etheresia

2012-06-01

For the study of cellular ultrastructure, the sample needs to be stabilized by fixation, with the ultimate aim to preserve the native tissue organization and to protect the tissue against later stages of preparation. Chemical and freezing fixation are most used, and chemical fixation employs agents that permeate tissues and cells by diffusion and covalently bind with their major biochemical constituents to fix them. Most widely used chemical fixatives are aldehydes, e.g., formaldehyde and glutaraldehyde, which are noncoagulating, crosslinking agents. Cryofixation methods for ultrastructural studies are also popular, and high-pressure freezing immobilizes all cell constituents and arrests biological activity by removing the thermal energy from the system. In the current research, we used platelet-rich plasma (PRP) to study expansive fibrin fibers and platelet ultrastructure to compare the two fixation techniques. We also used thrombin and calcium chloride as a clotting agent to determine the technique most suitable for the formation of extensive fibrin networks. Chemically fixated fibrin fibers were more compact and condensed and also showed a banding pattern on longitudinal sections. High-pressure frozen samples were more dispersed while platelets fixated showed better preserved cellular membranes and organelle structure. PRP coagulated by addition of CaCl(2) showed blood platelets that are noticeably more activated compared with PRP; however, with thrombin, a sharp ultrastructure was seen. We conclude that PRP mixed with thrombin, and freeze substituted, is the most suitable method for the study of extensive fibrin fibers as well as platelets. Copyright © 2011 Wiley Periodicals, Inc.

Methods of Monitoring Cell Fate and Tissue Growth in Three-Dimensional Scaffold-Based Strategies for In Vitro Tissue Engineering.

Science.gov (United States)

Leferink, Anne M; van Blitterswijk, Clemens A; Moroni, Lorenzo

2016-08-01

In the field of tissue engineering, there is a need for methods that allow assessing the performance of tissue-engineered constructs noninvasively in vitro and in vivo. To date, histological analysis is the golden standard to retrieve information on tissue growth, cellular distribution, and cell fate on tissue-engineered constructs after in vitro cell culture or on explanted specimens after in vivo applications. Yet, many advances have been made to optimize imaging techniques for monitoring tissue-engineered constructs with a sub-mm or μm resolution. Many imaging modalities have first been developed for clinical applications, in which a high penetration depth has been often more important than lateral resolution. In this study, we have reviewed the current state of the art in several imaging approaches that have shown to be promising in monitoring cell fate and tissue growth upon in vitro culture. Depending on the aimed tissue type and scaffold properties, some imaging methods are more applicable than others. Optical methods are mostly suited for transparent materials such as hydrogels, whereas magnetic resonance-based methods are mostly applied to obtain contrast between hard and soft tissues regardless of their transparency. Overall, this review shows that the field of imaging in scaffold-based tissue engineering is developing at a fast pace and has the potential to overcome the limitations of destructive endpoint analysis.

An improved calcium chloride method preparation and ...

African Journals Online (AJOL)

Transformation is one of the fundamental and essential molecular cloning techniques. In this paper, we have reported a modified method for preparation and transformation of competent cells. This modified method, improved from a classical protocol, has made some modifications on the concentration of calcium chloride ...

Preparation and characterization of chitosan-natural nano hydroxyapatite-fucoidan nanocomposites for bone tissue engineering.

Science.gov (United States)

Lowe, Baboucarr; Venkatesan, Jayachandran; Anil, Sukumaran; Shim, Min Suk; Kim, Se-Kwon

2016-12-01

Solid three dimensional (3D) composite scaffolds for bone tissue engineering were prepared using the freeze-drying method. The scaffolds were composed of chitosan, natural nano-hydroxyapatite (nHA) and fucoidan in the following combinations: chitosan, chitosan-fucoidan, chitosan-nHA, and chitosan-nHA-fucoidan. Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and optical microscopy (OM) were used to determine the physiochemical constituents and the morphology of the scaffolds. The addition of nHA into the chitosan-fucoidan composite scaffold reduced the water uptake and water retention. FT-IR analysis confirmed the presence of a phosphate group in the chitosan-nHA-fucoidan scaffold. This group is present because of the presence of nHA (isolated via alkaline hydrolysis from salmon fish bones). Microscopic results indicated that the dispersion of nHA and fucoidan in the chitosan matrix was uniform with a pore size of 10-400μm. The composite demonstrated a suitable micro architecture for cell growth and nutrient supplementation. This compatibility was further elucidated in vitro using periosteum-derived mesenchymal stem cells (PMSCs). The cells demonstrated high biocompatibility and excellent mineralization for the chitosan-nHA-fucoidan scaffold. We believe that a chitosan-nHA-fucoidan composite is a promising biomaterial for the scaffold that can be used for bone tissue regeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

A method to obtain reference images for evaluation of ultrasonic tissue characterization techniques

DEFF Research Database (Denmark)

Jensen, M.S.; Wilhjelm, Jens E.; Sahl, B.

2002-01-01

of the macroscopic photograph, due to the histological preparation process. The histological information was "mapped back" into the format of the ultrasound images the following way: On the macroscopic images, outlines were drawn manually which defined the border of the tissue. These outlines were superimposed...... of the various tissue types. Specifically, the macroscopic image revealed the borders between the different tissues, while the histological image identified the four tissue types. A set of 12 reference images based on modified macroscopic outlines was created. The overlap between the ultrasound images...... and the macroscopic images-which are the geometrical basis for the final reference images-was between 77% and 93%. A set of 12 reference images spaced 2.5 mm, identifying spatial location of four different tissue types in porcine muscle has been created. With the reference images, it is possible to quantitatively...

Preparation of collagen/polyurethane/knitted silk as a composite scaffold for tendon tissue engineering.

Science.gov (United States)

Sharifi-Aghdam, Maryam; Faridi-Majidi, Reza; Derakhshan, Mohammad Ali; Chegeni, Arash; Azami, Mahmoud

2017-07-01

The main objective of this study was to prepare a hybrid three-dimensional scaffold that mimics natural tendon tissues. It has been found that a knitted silk shows good mechanical strength; however, cell growth on the bare silk is not desirable. Hence, electrospun collagen/polyurethane combination was used to cover knitted silk. A series of collagen and polyurethane solutions (4%-7% w/v) in aqueous acetic acid were prepared and electrospun. According to obtained scanning electron microscopy images from pure collagen and polyurethane nanofibers, concentration was set constant at 5% (w/v) for blend solutions of collagen/polyurethane. Afterward, blend solutions with the weight ratios of 75/25, 50/50 and 25/75 were electrospun. Scanning electron microscopy images demonstrated the smooth and uniform morphology for the optimized nanofibers. The least fibers diameter among three weight ratios was found for collagen/polyurethane (25/75) which was 100.86 ± 40 nm and therefore was selected to be electrospun on the knitted silk. Attenuated total reflectance-Fourier transform infrared spectra confirmed the chemical composition of obtained electrospun nanofibers on the knitted silk. Tensile test of the specimens including blend nanofiber, knitted silk and commercial tendon substitute examined and indicated that collagen/polyurethane-coated knitted silk has appropriate mechanical properties as a scaffold for tendon tissue engineering. Then, Alamar Blue assay of the L929 fibroblast cell line seeded on the prepared scaffolds demonstrated appropriate viability of the cells with a significant proliferation on the scaffold containing more collagen content. The results illustrate that the designed structure would be promising for being used as a temporary substitute for tendon repair.

Brain tissue stiffness is a sensitive marker for acidosis.

Science.gov (United States)

Holtzmann, Kathrin; Gautier, Hélène O B; Christ, Andreas F; Guck, Jochen; Káradóttir, Ragnhildur Thóra; Franze, Kristian

2016-09-15

Carbon dioxide overdose is frequently used to cull rodents for tissue harvesting. However, this treatment may lead to respiratory acidosis, which potentially could change the properties of the investigated tissue. Mechanical tissue properties often change in pathological conditions and may thus offer a sensitive generic readout for changes in biological tissues with clinical relevance. In this study, we performed force-indentation measurements with an atomic force microscope on acute cerebellar slices from adult rats to test if brain tissue undergoes changes following overexposure to CO2 compared to other methods of euthanasia. The pH significantly decreased in brain tissue of animals exposed to CO2. Concomitant with the drop in pH, cerebellar grey matter significantly stiffened. Tissue stiffening was reproduced by incubation of acute cerebellar slices in acidic medium. Tissue stiffness provides an early, generic indicator for pathophysiological changes in the CNS. Atomic force microscopy offers unprecedented high spatial resolution to detect such changes. Our results indicate that the stiffness particularly of grey matter strongly correlates with changes of the pH in the cerebellum. Furthermore, the method of tissue harvesting and preparation may not only change tissue stiffness but very likely also other physiologically relevant parameters, highlighting the importance of appropriate sample preparation. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Preparation of a Carbon Doped Tissue-Mimicking Material with High Dielectric Properties for Microwave Imaging Application

Directory of Open Access Journals (Sweden)

Siang-Wen Lan

2016-07-01

Full Text Available In this paper, the oil-in-gelatin based tissue-mimicking materials (TMMs doped with carbon based materials including carbon nanotube, graphene ink or lignin were prepared. The volume percent for gelatin based mixtures and oil based mixtures were both around 50%, and the doping amounts were 2 wt %, 4 wt %, and 6 wt %. The effect of doping material and amount on the microwave dielectric properties including dielectric constant and conductivity were investigated over an ultra-wide frequency range from 2 GHz to 20 GHz. The coaxial open-ended reflection technology was used to evaluate the microwave dielectric properties. Six measured values in different locations of each sample were averaged and the standard deviations of all the measured dielectric properties, including dielectric constant and conductivity, were less than one, indicating a good uniformity of the prepared samples. Without doping, the dielectric constant was equal to 23 ± 2 approximately. Results showed with doping of carbon based materials that the dielectric constant and conductivity both increased about 5% to 20%, and the increment was dependent on the doping amount. By proper selection of doping amount of the carbon based materials, the prepared material could map the required dielectric properties of special tissues. The proposed materials were suitable for the phantom used in the microwave medical imaging system.

Photoactivated methods for enabling cartilage-to-cartilage tissue fixation

Science.gov (United States)

Sitterle, Valerie B.; Roberts, David W.

2003-06-01

The present study investigates whether photoactivated attachment of cartilage can provide a viable method for more effective repair of damaged articular surfaces by providing an alternative to sutures, barbs, or fibrin glues for initial fixation. Unlike artificial materials, biological constructs do not possess the initial strength for press-fitting and are instead sutured or pinned in place, typically inducing even more tissue trauma. A possible alternative involves the application of a photosensitive material, which is then photoactivated with a laser source to attach the implant and host tissues together in either a photothermal or photochemical process. The photothermal version of this method shows potential, but has been almost entirely applied to vascularized tissues. Cartilage, however, exhibits several characteristics that produce appreciable differences between applying and refining these techniques when compared to previous efforts involving vascularized tissues. Preliminary investigations involving photochemical photosensitizers based on singlet oxygen and electron transfer mechanisms are discussed, and characterization of the photodynamic effects on bulk collagen gels as a simplified model system using FTIR is performed. Previous efforts using photothermal welding applied to cartilaginous tissues are reviewed.

Glycomic profiling of tissue sections by LC-MS.

Science.gov (United States)

Hu, Yunli; Zhou, Shiyue; Khalil, Sarah I; Renteria, Calvin L; Mechref, Yehia

2013-04-16

Because routine preparation of glycan samples involves multiple reaction and cleaning steps at which sample loss occurs, glycan analysis is typically performed using large tissue samples. This type of analysis yields no detailed molecular spatial information and requires special care to maintain proper storage and shipping conditions. We describe here a new glycan sample preparation protocol using minimized sample preparation steps and optimized procedures. Tissue sections and spotted samples first undergo on-surface enzymatic digestion to release N-glycans. The released glycans are then reduced and permethylated prior to online purification and LC-electrospray ionization (ESI)-MS analysis. The efficiency of this protocol was initially evaluated using model glycoproteins and human blood serum (HBS) spotted on glass or Teflon slides. The new protocol permitted the detection of permethylated N-glycans derived from 10 ng RNase B. On the other hand, 66 N-glycans were identified when injecting the equivalent of permethylated glycans derived from a 0.1-μL aliquot of HBS. On-tissue enzymatic digestion of nude mouse brain tissue permitted the detection of 43 N-glycans. The relative peak areas of these 43 glycans were comparable to those from a C57BL/6 mouse reported by the Consortium for Functional Glycomics (CFG). However, the sample size analyzed in the protocol described here was substantially smaller than for the routine method (submicrogram vs mg). The on-tissue N-glycan profiling method permits high sensitivity and reproducibility and can be widely applied to assess the spatial distribution of glycans associated with tissue sections, and may be correlated with immunoflourescence imaging when adjacent tissue sections are analyzed.

Low platinum catalyst and method of preparation

Energy Technology Data Exchange (ETDEWEB)

Liu, Di-Jia; Chong, Lina

2017-11-21

A low platinum catalyst and method for making same. The catalyst comprises platinum-transition metal bimetallic alloy microcrystallites over a transition metal-nitrogen-carbon composite. A method of making a catalyst comprises preparation of transition metal organic frameworks, infusion of platinum, thermal treatment, and reduction to form the microcrystallites and composite.

Rapid preparation method for technetium-99m bicisate

Energy Technology Data Exchange (ETDEWEB)

Hung, J.C. [Nuclear Medicine, Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minnesota (United States); Chowdhury, S. [Nuclear Medicine, Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minnesota (United States); Redfern, M.G. [Nuclear Medicine, Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minnesota (United States); Mahoney, D.W. [Section of Biostatistics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota (United States)

1997-06-10

The method currently recommended for the preparation of technetium-99m bicisate ({sup 99m}Tc-bicisate) requires a lengthy 30-min incubation at room temperature. The purpose of this study was to evaluate an alternative method to shorten the preparation time. {sup 99m}Tc-bicisate was prepared with 3.7 GBq (100 mCi) {sup 99m}Tc according to the manufacturer`s instructions, except for the final incubation step, which was replaced with the microwave heating procedure. A standard thin-layer chromatography (TLC) method (i.e., Baker-Flex silica gel IB-F TLC plate with ethyl acetate as mobile phase) was used for the determination of the radiochemical purity (RCP) of {sup 99m}Tc-bicisate. Our evaluation with different microwave heating processes (300 W with different heating times) demonstrated that as the microwave heating temperature was increased (i.e., 44 -71 C), an increased percentage of samples reached 95% within 5 min post preparation (n=58). The highest RCP value (i.e., 97.4%{+-}0.5%, n=10) could be obtained immediately after an 8-s microwave heating time at 300 W (microwave temperature at 69 C), and an average RCP value of 96.4%{+-}1.3% (n=90) was maintained throughout the 24-h evaluation period. However, the trend seemed to reverse at higher microwave temperatures (i.e., 76 -90 C), which reconfirmed our initial findings that overheating had no benefit for the preparation of {sup 99m}Tc-bicisate. To ensure that temperature was the only determining factor, a hot water incubator set at 69 C was used (n=6). Similar RCP results were achieved. In conclusion, the use of a microwave oven at a low heat cycle provides a rapid and efficient way to prepare {sup 99m}Tc-bicisate. (orig.). With 3 figs., 1 tab.

Comparative facile methods for preparing graphene oxide-hydroxyapatite for bone tissue engineering.

Science.gov (United States)

Raucci, M G; Giugliano, D; Longo, A; Zeppetelli, S; Carotenuto, G; Ambrosio, L

2017-08-01

Motivated by the success of using graphene oxide (GO) as a nanofiller of composites, there is a drive to search for this new kind of carbon material as a bioactive component in ceramic materials. In the present study, biomineralized GO was prepared by two different approaches, represented by in situ sol-gel synthesis and biomimetic treatment. It was found that in the biocomposites obtained by the sol-gel approach, the spindle-like hydroxyapatite nanoparticles, with a diameter of ca. 5 ± 0.37 nm and a length of ca. 70 ± 2.5 nm, were presented randomly and strongly on the surface. The oxygen-containing functional groups, such as hydroxyl and carbonyl, present on the basal plane and edges of the GO sheets, play an important role in anchoring calcium ions, as demonstrated by FT-IR and TEM investigations. A different result was obtained for biocomposites after biomimetic treatment: an amorphous calcium phosphate on GO sheet was observed after 5 days of treatment. These different approaches resulted in a diverse effect on the proliferation and differentiation of osteogenic mesenchymal stem cells. In fact, in biocomposites prepared by the sol-gel approach the expression of an early marker of osteogenic differentiation, ALP, increases with the amount of GO in the first days of cell culture. Meanwhile, biomimetic materials sustain cell viability and proliferation, even if the expression of alkaline phosphatase activity in a basal medium is delayed. These findings may provide new prospects for utilizing GO-based hydroxyapatite biocomposites in bone repair, bone augmentation and coating of biomedical implants and broaden the application of GO sheets in biological areas. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

[Strategies to choose scaffold materials for tissue engineering].

Science.gov (United States)

Gao, Qingdong; Zhu, Xulong; Xiang, Junxi; Lü, Yi; Li, Jianhui

2016-02-01

Current therapies of organ failure or a wide range of tissue defect are often not ideal. Transplantation is the only effective way for long time survival. But it is hard to meet huge patients demands because of donor shortage, immune rejection and other problems. Tissue engineering could be a potential option. Choosing a suitable scaffold material is an essential part of it. According to different sources, tissue engineering scaffold materials could be divided into three types which are natural and its modified materials, artificial and composite ones. The purpose of tissue engineering scaffold is to repair the tissues or organs damage, so could reach the ideal recovery in its function and structure aspect. Therefore, tissue engineering scaffold should even be as close as much to the original tissue or organs in function and structure. We call it "organic scaffold" and this strategy might be the drastic perfect substitute for the tissues or organs in concern. Optimized organization with each kind scaffold materials could make up for biomimetic structure and function of the tissue or organs. Scaffold material surface modification, optimized preparation procedure and cytosine sustained-release microsphere addition should be considered together. This strategy is expected to open new perspectives for tissue engineering. Multidisciplinary approach including material science, molecular biology, and engineering might find the most ideal tissue engineering scaffold. Using the strategy of drawing on each other strength and optimized organization with each kind scaffold material to prepare a multifunctional biomimetic tissue engineering scaffold might be a good method for choosing tissue engineering scaffold materials. Our research group had differentiated bone marrow mesenchymal stem cells into bile canaliculi like cells. We prepared poly(L-lactic acid)/poly(ε-caprolactone) biliary stent. The scaffold's internal played a part in the long-term release of cytokines which

Mandibular Bone and Soft Tissues Necrosis Caused by an Arsenical Endodontic Preparation Treated with Piezoelectric Device

Directory of Open Access Journals (Sweden)

A. Giudice

2013-01-01

Full Text Available This paper describes a case of wide mandibular bone necrosis associated with significant soft tissues injury after using an arsenical endodontic preparation in the right lower second molar for endodontic purpose. Authors debate about the hazardous effects of the arsenic paste and the usefulness of piezosurgery for treatment of this drug related bone necrosis.

Vitrification of in vitro matured oocytes collected from surplus ovarian medulla tissue resulting from fertility preservation of ovarian cortex tissue

DEFF Research Database (Denmark)

Yin, Huiqun; Jiang, Hong; Kristensen, Stine Gry

2016-01-01

PURPOSE: The aim of the study was to investigate the maturation rate of immature oocytes collected from ovarian medulla tissue normally discarded during preparation of ovarian cortical tissue for fertility preservation. Further we evaluated survival of derived MII oocytes following vitrification...... and warming. METHODS: 36 patients aged from 8 to 41 years who had one ovary excised for fertility preservation were included. Oocytes were collected from the medulla tissue and matured in vitro 44-48 h followed by vitrification. Number of oocytes collected, the rates of maturation and post-warming survival...... of cortical tissue may pose a risk of relapse, but the IVM approach is currently too inefficient to be the only method used for fertility preservation....

Three-dimensional assessment of brain tissue morphology

Science.gov (United States)

Müller, Bert; Germann, Marco; Jeanmonod, Daniel; Morel, Anne

2006-08-01

The microstructure of brain tissues becomes visible using different types of optical microscopy after the tissue sectioning. This preparation procedure introduces stress and strain in the anisotropic and inhomogeneous soft tissue slices, which are several 10 μm thick. Consequently, the three-dimensional dataset, generated out of the two-dimensional images with lateral submicrometer resolution, needs algorithms to correct the deformations, which can be significant for mellow tissue such as brain segments. The spatial resolution perpendicular to the slices is much worse with respect to the lateral sub-micrometer resolution. Therefore, we propose as complementary method the synchrotron-radiation-based micro computed tomography (SRμCT), which avoids any kind of preparation artifacts due to sectioning and histological processing and yields true micrometer resolution in the three orthogonal directions. The visualization of soft matter by the use of SRμCT, however, is often based on elaborate staining protocols, since the tissue exhibits (almost) the same x-ray absorption as the surrounding medium. Therefore, it is unexpected that human tissue from the pons and the medulla oblongata in phosphate buffer show several features such as the blood vessels and the inferior olivary nucleus without staining. The value of these tomograms lies especially in the precise non-rigid registration of the different sets of histological slices. Applications of this method to larger pieces of brain tissue, such as the human thalamus are planned in the context of stereotactic functional neurosurgery.

Magnetic Properties of Ni-Zn Ferrite Prepared with the Layered Precursor Method

International Nuclear Information System (INIS)

Zhou Xin; Hou Zhi-Ling; Li Feng; Qi Xin

2010-01-01

We prepare NiZnFe 2 O 4 soft magnetic ferrites with different molar ratios with the layered precursor method and investigate their magnetic properties. In the layered precursor, metal ions are scattered on the layer plate in a certain way on account of the effect of lowest lattice energy and lattice orientation. After high temperature calcinations, spinel ferrites with uniform structural component and single magnetic domain can be obtained, and the magnetic property is improved greatly. NiZnFe 2 O 4 ferrites prepared have the best specific saturation magnetization of 79.15 emu·g −1 , higher than that of 68 emu·g −1 prepared by the chemical co-precipitation method and that of 59 emu·g −1 prepared by the emulsion-gel method. Meanwhile the coercivity of NiZnFe 2 O 4 ferrites prepared by layered precursor method is 14 kA·m −1 , lower than that of 50 emu·g −1 prepared by the co-precipitation method and that of 59 emu·g −1 prepared by the emulsion-gel method. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Method for preparation of borax decahydrate

International Nuclear Information System (INIS)

Dujnedenko, V.I.; Chumaevskij, V.A.; Kovalev, A.S.; Gabova, E.L.; Suvorova, M.R.; Smirnova, V.G.; Smirnov, A.S.

1990-01-01

A highly productive method of borax decahydrate preparation, consisting in the mixing of boric acid, soda and mother solution at the temperature not exceeding 40 deg is described. The mixture is supplied to borax circulating solution at the temperature of 85-95 deg. After crystallization borax decahydrate is isolated from mother solution and solution is directed for mixing with boric acid and soda. The given method permits to increase the process productivity 3.75-4.50 fold

Comparison of extraction methods for quantifying vitamin E from animal tissues.

Science.gov (United States)

Xu, Zhimin

2008-12-01

Four extraction methods: (1) solvent (SOL), (2) ultrasound assisted solvent (UA), (3) saponification and solvent (SP), and (4) saponification and ultrasound assisted solvent (SP-UA), were used in sample preparation for quantifying vitamin E (tocopherols) in chicken liver and plasma samples. The extraction yields of SOL, UA, SP, and SP-UA methods obtained by adding delta-tocopherol as internal reference were 95%, 104%, 65%, and 62% for liver and 98%, 103%, 97%, and 94% for plasma, respectively. The methods with saponification significantly affected the stabilities of tocopherols in liver samples. The measured values of alpha- and gamma-tocopherols using the solvent only extraction (SOL) method were much lower than that using any of the other extraction methods. This indicated that less of the tocopherols in those samples were in a form that could be extracted directly by solvent. The measured value of alpha-tocopherol in the liver sample using the ultrasound assisted solvent (UA) method was 1.5-2.5 times of that obtained from the saponification and solvent (SP) method. The differences in measured values of tocopherols in the plasma samples by using the two methods were not significant. However, the measured value of the saponification and ultrasound assisted solvent (SP-UA) method was lower than either the saponification and solvent (SP) or the ultrasound assisted solvent (UA) method. Also, the reproducibility of the ultrasound assisted solvent (UA) method was greater than any of the saponification methods. Compared with the traditional saponification method, the ultrasound assisted solvent method could effectively extract tocopherols from sample matrix without any chemical degradation reactions, especially for complex animal tissue such as liver.

THE USE OF A NOVEL ALDEHYDE-FUNCTIONALIZED CHITOSAN HYDROGEL TO PREPARE POROUS TUBULAR SCAFFOLDS FOR VASCULAR TISSUE ENGINEERING APPLICATIONS

Directory of Open Access Journals (Sweden)

Eduardo P. Azevedo

Full Text Available In this work, porous tubular scaffolds were prepared from a novel water soluble aldehyde-functionalized chitosan (ALDCHIT hydrogel, which was obtained by dissolving this chitosan derivative in water and using oxidized dextrose (OXDEXT as the crosslinking agent at different ALDCHIT:OXDEXT mole ratios (10:1, 10:2 and 10:4. By increasing the amount of OXDEXT in respect to ALDCHIT the hydrogels became more rigid and could absorb more than 200% of its weight in water. Since the ALDCHIT:OXDEXT 10:4 was the most stable hydrogel, its ability to form porous tubular scaffolds was investigated. The tubular scaffolds were prepared by the lyophilization method, where the orientation of the pores was controlled by exposing either the internal or the external surface of the frozen hydrogel during the sublimation step. When only the inner surface of the frozen hydrogel was exposed, tubular scaffolds with a highly porous lumen and a sealed outer surface were obtained, where the orientation of the pores, their sizes and interconnectivity seem to be optimum for vascular tissue engineering application.

Radiosterilization of Tissues Preserved for Clinical Purposes: Effect on Tissue Antigenicity

International Nuclear Information System (INIS)

Ostrowski, K.; Kossowska, B.; Moskalewski, S.; Komender, A.; Kurnatowski, W.

1967-01-01

The first part of the paper contains practical considerations on the radiosterilization of preserved human bone, human and calf cartilage, cow’s fascia and aponeurosis, based on material from the Tissue Bank which produces about 2500 transplants yearly. The method of preservation and packing of each type of tissue is mentioned briefly. The preserved tissues are irradiated in a cobalt bomb or in a nuclear reactor. The conditions of irradiation and the control of sterility are described. The advantages and disadvantages of radiosterilization are discussed on the basis of the authors’ own experience and clinical reports of surgeons using radiosterilized tissues in practice. In the second part of the paper, experimental studies on the influence of freezing, lyophilization and radiosterilization on tissue antigenicity are reported. The regional lymph node reacts to an antigenic stimulus by an increased production of large, pyroninophylic cells, so-called ''blast'' cells. The rabbits used as recipients received grafts of allogeneic cancellous bone, fresh or subjected to different experimental procedures. Smears from lymph node cell suspension were prepared and the percentage of blast cells was estimated. On the basis of the lymph node response, it appears that freezing and lyophilization, as well as radiosterilization, may abolish the antigenicity of cancellous bone. The practical implication of these results for methods of preservation of tissues for clinical purposes is discussed. (author)

Effect of preparation methods on dispersion stability and electrochemical performance of graphene sheets

International Nuclear Information System (INIS)

Chen, Li; Li, Na; Zhang, Mingxia; Li, Pinnan; Lin, Zhengping

2017-01-01

Chemical exfoliation is one of the most important strategies for preparing graphene. The aggregation of graphene sheets severely prevents graphene from exhibiting excellent properties. However, there are no attempts to investigate the effect of preparation methods on the dispersity of graphene sheets. In this study, three chemical exfoliation methods, including Hummers method, modified Hummers method, and improved method, were used to prepare graphene sheets. The influence of preparation methods on the structure, dispersion stability in organic solvents, and electrochemical properties of graphene sheets were investigated. Fourier transform infrared microscopy, Raman spectra, transmission electron microscopy, and UV–vis spectrophotometry were employed to analyze the structure of the as-prepared graphene sheets. The results showed that graphene prepared by improved method exhibits excellent dispersity and stability in organic solvents without any additional stabilizer or modifier, which is attributed to the completely exfoliation and regular structure. Moreover, cyclic voltammetric and electrochemical impedance spectroscopy measurements showed that graphene prepared by improved method exhibits superior electrochemical properties than that prepared by the other two methods. - Graphical abstract: Graphene oxides with different oxidation degree were obtained via three methods, and then graphene with different crystal structures were created by chemical reduction of exfoliated graphene oxides. - Highlights: • Graphene oxides with different oxidation degree were obtained via three oxidation methods. • The influence of oxidation methods on microstructure of graphene was investigated. • The effect of oxidation methods on dispersion stability of graphene was investigated. • The effect of oxidation methods on electrochemical properties of graphene was discussed.

Effect of preparation methods on dispersion stability and electrochemical performance of graphene sheets

Energy Technology Data Exchange (ETDEWEB)

Chen, Li, E-mail: chenli1981@lut.cn; Li, Na; Zhang, Mingxia; Li, Pinnan; Lin, Zhengping

2017-05-15

Chemical exfoliation is one of the most important strategies for preparing graphene. The aggregation of graphene sheets severely prevents graphene from exhibiting excellent properties. However, there are no attempts to investigate the effect of preparation methods on the dispersity of graphene sheets. In this study, three chemical exfoliation methods, including Hummers method, modified Hummers method, and improved method, were used to prepare graphene sheets. The influence of preparation methods on the structure, dispersion stability in organic solvents, and electrochemical properties of graphene sheets were investigated. Fourier transform infrared microscopy, Raman spectra, transmission electron microscopy, and UV–vis spectrophotometry were employed to analyze the structure of the as-prepared graphene sheets. The results showed that graphene prepared by improved method exhibits excellent dispersity and stability in organic solvents without any additional stabilizer or modifier, which is attributed to the completely exfoliation and regular structure. Moreover, cyclic voltammetric and electrochemical impedance spectroscopy measurements showed that graphene prepared by improved method exhibits superior electrochemical properties than that prepared by the other two methods. - Graphical abstract: Graphene oxides with different oxidation degree were obtained via three methods, and then graphene with different crystal structures were created by chemical reduction of exfoliated graphene oxides. - Highlights: • Graphene oxides with different oxidation degree were obtained via three oxidation methods. • The influence of oxidation methods on microstructure of graphene was investigated. • The effect of oxidation methods on dispersion stability of graphene was investigated. • The effect of oxidation methods on electrochemical properties of graphene was discussed.

Application of infrared spectroscopy for diagnosis of kidney tumor tissue

OpenAIRE

Bandzevičiūtė, Rimantė

2016-01-01

Application of Infrared Spectroscopy for Diagnosis of Kidney Tumor Tissue It is possible to apply the technique of an attenuated total reflection of infrared radiation (ATR IR) for the characterisation of the removed tissues during the surgery. Application of this method for interstitium of the removed tissue does not require any specific sample preparation. For this reason ATR IR technique applied for the interstitium allows to get information about tissues immediately after surgical operati...

Sintered nuclear fuel and method of preparing same

International Nuclear Information System (INIS)

Abate-Daga, G.; Amato, I.

1975-01-01

A description is given of a method of preparing a nuclear fuel containing a consumable nuclear poison uniformly distributed therein in the form of coated micro-spheres of between 10 and 2,000 microns diameter, consisting in preparing sintered micro-spheres of the consumable poison, covering those micro-spheres with a protective coating and incorporating the coated micro-spheres into uranium dioxide powder, followed by sintering

An UPLC-MS/MS method for highly sensitive high-throughput analysis of phytohormones in plant tissues

Directory of Open Access Journals (Sweden)

Balcke Gerd Ulrich

2012-11-01

Full Text Available Abstract Background Phytohormones are the key metabolites participating in the regulation of multiple functions of plant organism. Among them, jasmonates, as well as abscisic and salicylic acids are responsible for triggering and modulating plant reactions targeted against pathogens and herbivores, as well as resistance to abiotic stress (drought, UV-irradiation and mechanical wounding. These factors induce dramatic changes in phytohormone biosynthesis and transport leading to rapid local and systemic stress responses. Understanding of underlying mechanisms is of principle interest for scientists working in various areas of plant biology. However, highly sensitive, precise and high-throughput methods for quantification of these phytohormones in small samples of plant tissues are still missing. Results Here we present an LC-MS/MS method for fast and highly sensitive determination of jasmonates, abscisic and salicylic acids. A single-step sample preparation procedure based on mixed-mode solid phase extraction was efficiently combined with essential improvements in mobile phase composition yielding higher efficiency of chromatographic separation and MS-sensitivity. This strategy resulted in dramatic increase in overall sensitivity, allowing successful determination of phytohormones in small (less than 50 mg of fresh weight tissue samples. The method was completely validated in terms of analyte recovery, sensitivity, linearity and precision. Additionally, it was cross-validated with a well-established GC-MS-based procedure and its applicability to a variety of plant species and organs was verified. Conclusion The method can be applied for the analyses of target phytohormones in small tissue samples obtained from any plant species and/or plant part relying on any commercially available (even less sensitive tandem mass spectrometry instrumentation.

Physical non-viral gene delivery methods for tissue engineering.

Science.gov (United States)

Mellott, Adam J; Forrest, M Laird; Detamore, Michael S

2013-03-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that "fits-all" cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications.

Physical non-viral gene delivery methods for tissue engineering

Science.gov (United States)

Mellott, Adam J.; Forrest, M. Laird; Detamore, Michael S.

2016-01-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that “fits-all” cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications. PMID:23099792

Development of Preparation Methods for Alkaline Anion Exchange Membranes by Radiation

International Nuclear Information System (INIS)

Shin, Jun Hwa; Nho, Young Chang; Sohn, Joon Yong

2010-01-01

The objective of this project is to contribute to the environmentally friendly fuel cell system by developing a radiation grafting method for the preparation of anion exchange membranes for alkaline fuel cell and finally to the radiation technology industry. In this project, the preparation methods for the VBC-grafted fluoropolymer films using radiation have been developed and anion exchange membranes have been prepared via the reaction between the VBC-grafted fluoropolymer films and amines. The prepared anion exchange membranes were characterized and the performance of the membranes were evaluated

A novel liquid chromatography/mass spectrometry method for determination of neurotransmitters in brain tissue: Application to human tauopathies.

Science.gov (United States)

Forgacsova, Andrea; Galba, Jaroslav; Garruto, Ralph M; Majerova, Petra; Katina, Stanislav; Kovac, Andrej

2018-01-15

Neurotransmitters, small molecules widely distributed in the central nervous system are essential in transmitting electrical signals across neurons via chemical communication. Dysregulation of these chemical signaling molecules is linked to numerous neurological diseases including tauopathies. In this study, a precise and reliable liquid chromatography method was established with tandem mass spectrometry detection for the simultaneous determination of aspartic acid, asparagine, glutamic acid, glutamine, γ-aminobutyric acid, N-acetyl-l-aspartic acid, pyroglutamic acid, acetylcholine and choline in human brain tissue. The method was successfully applied to the analysis of human brain tissues from three different tauopathies; corticobasal degeneration, progressive supranuclear palsy and parkinsonism-dementia complex of Guam. Neurotransmitters were analyzed on ultra-high performance chromatography (UHPLC) using an ethylene bridged hybrid amide column coupled with tandem mass spectrometry (MS/MS). Identification and quantification of neurotransmitters was carried out by ESI+ mass spectrometry detection. We optimized sample preparation to achieve simple and fast extraction of all nine analytes. Our method exhibited an excellent linearity for all analytes (all coefficients of determination >0.99), with inter-day and intra-day precision yielding relative standard deviations 3.2%-11.2% and an accuracy was in range of 92.6%-104.3%. The present study, using the above method, is the first to demonstrate significant alterations of brain neurotransmitters caused by pathological processes in the brain tissues of patient with three different tauopathies. Copyright © 2017 Elsevier B.V. All rights reserved.

Water-equivalent solid sources prepared by means of two distinct methods

International Nuclear Information System (INIS)

Koskinas, Marina F.; Yamazaki, Ione M.; Potiens Junior, Ademar

2014-01-01

The Nuclear Metrology Laboratory at IPEN is involved in developing radioactive water-equivalent solid sources prepared from an aqueous solution of acrylamide using two distinct methods for polymerization. One of them is the polymerization by high dose of 60 Co irradiation; in the other method the solid matrix-polyacrylamide is obtained from an aqueous solution composed by acrylamide, catalyzers and an aliquot of a radionuclide. The sources have been prepared in cylindrical geometry. In this paper, the study of the distribution of radioactive material in the solid sources prepared by both methods is presented. (author)

Methods to Quantify Nickel in Soils and Plant Tissues

Directory of Open Access Journals (Sweden)

Bruna Wurr Rodak

2015-06-01

Full Text Available In comparison with other micronutrients, the levels of nickel (Ni available in soils and plant tissues are very low, making quantification very difficult. The objective of this paper is to present optimized determination methods of Ni availability in soils by extractants and total content in plant tissues for routine commercial laboratory analyses. Samples of natural and agricultural soils were processed and analyzed by Mehlich-1 extraction and by DTPA. To quantify Ni in the plant tissues, samples were digested with nitric acid in a closed system in a microwave oven. The measurement was performed by inductively coupled plasma/optical emission spectrometry (ICP-OES. There was a positive and significant correlation between the levels of available Ni in the soils subjected to Mehlich-1 and DTPA extraction, while for plant tissue samples the Ni levels recovered were high and similar to the reference materials. The availability of Ni in some of the natural soil and plant tissue samples were lower than the limits of quantification. Concentrations of this micronutrient were higher in the soil samples in which Ni had been applied. Nickel concentration differed in the plant parts analyzed, with highest levels in the grains of soybean. The grain, in comparison with the shoot and leaf concentrations, were better correlated with the soil available levels for both extractants. The methods described in this article were efficient in quantifying Ni and can be used for routine laboratory analysis of soils and plant tissues.

Culture methods of allograft musculoskeletal tissue samples in Australian bacteriology laboratories.

Science.gov (United States)

Varettas, Kerry

2013-12-01

Samples of allograft musculoskeletal tissue are cultured by bacteriology laboratories to determine the presence of bacteria and fungi. In Australia, this testing is performed by 6 TGA-licensed clinical bacteriology laboratories with samples received from 10 tissue banks. Culture methods of swab and tissue samples employ a combination of solid agar and/or broth media to enhance micro-organism growth and maximise recovery. All six Australian laboratories receive Amies transport swabs and, except for one laboratory, a corresponding biopsy sample for testing. Three of the 6 laboratories culture at least one allograft sample directly onto solid agar. Only one laboratory did not use a broth culture for any sample received. An international literature review found that a similar combination of musculoskeletal tissue samples were cultured onto solid agar and/or broth media. Although variations of allograft musculoskeletal tissue samples, culture media and methods are used in Australian and international bacteriology laboratories, validation studies and method evaluations have challenged and supported their use in recovering fungi and aerobic and anaerobic bacteria.

Nano-biolistics: a method of biolistic transfection of cells and tissues using a gene gun with novel nanometer-sized projectiles

Directory of Open Access Journals (Sweden)

Lummis Sarah CR

2011-06-01

Full Text Available Abstract Background Biolistic transfection is proving an increasingly popular method of incorporating DNA or RNA into cells that are difficult to transfect using traditional methods. The technique routinely uses 'microparticles', which are ~1 μm diameter projectiles, fired into tissues using pressurised gas. These microparticles are efficient at delivering DNA into cells, but cannot efficiently transfect small cells and may cause significant tissue damage, thus limiting their potential usefulness. Here we describe the use of 40 nm diameter projectiles - nanoparticles - in biolistic transfections to determine if they are a suitable alternative to microparticles. Results Examination of transfection efficiencies in HEK293 cells, using a range of conditions including different DNA concentrations and different preparation procedures, reveals similar behaviour of microparticles and nanoparticles. The use of nanoparticles, however, resulted in ~30% fewer damaged HEK293 cells following transfection. Biolistic transfection of mouse ear tissue revealed similar depth penetration for the two types of particles, and also showed that 20% in microparticle-transfected samples. Visualising details of small cellular structures was also considerably enhanced when using nanoparticles. Conclusions We conclude that nanoparticles are as efficient for biolistic transfection as microparticles, and are more appropriate for use in small cells, when examining cellular structures and/or where tissue damage is a problem.

Application of electrical stimulation for functional tissue engineering in vitro and in vivo

Science.gov (United States)

Park, Hyoungshin (Inventor); Freed, Lisa (Inventor); Vunjak-Novakovic, Gordana (Inventor); Langer, Robert (Inventor); Radisic, Milica (Inventor)

2013-01-01

The present invention provides new methods for the in vitro preparation of bioartificial tissue equivalents and their enhanced integration after implantation in vivo. These methods include submitting a tissue construct to a biomimetic electrical stimulation during cultivation in vitro to improve its structural and functional properties, and/or in vivo, after implantation of the construct, to enhance its integration with host tissue and increase cell survival and functionality. The inventive methods are particularly useful for the production of bioartificial equivalents and/or the repair and replacement of native tissues that contain electrically excitable cells and are subject to electrical stimulation in vivo, such as, for example, cardiac muscle tissue, striated skeletal muscle tissue, smooth muscle tissue, bone, vasculature, and nerve tissue.

A novel method for preparing microplastic fibers

Science.gov (United States)

Cole, Matthew

2016-10-01

Microscopic plastic (microplastic, 0.1 µm-5 mm) is a widespread pollutant impacting upon aquatic ecosystems across the globe. Environmental sampling has revealed synthetic fibers are prevalent in seawater, sediments and biota. However, microplastic fibers are rarely used in laboratory studies as they are unavailable for purchase and existing preparation techniques have limited application. To facilitate the incorporation of environmentally relevant microplastic fibers into future studies, new methods are required. Here, a novel cryotome protocol has been developed. Nylon, polyethylene terephthalate and polypropylene fibers (10-28 μm diameter) were aligned, embedded in water-soluble freezing agent, and sectioned (40-100 μm length) using a cryogenic microtome. Microplastic fibers were prepared to specified lengths (P < 0.05, ANOVA) and proved consistent in size. Fluorescent labelling of Nylon microfibers with Nile Red facilitated imaging. A 24 h feeding experiment confirmed bioavailability of 10 × 40 μm Nylon fibers to brine shrimp (Artemia sp). This protocol provides a consistent method for preparing standardised fibrous microplastics, with widths similar to those observed in the natural environment, which could ultimately lead to a better understanding of the biological and ecological effects of microplastic debris in the environment.

3D imaging of optically cleared tissue using a simplified CLARITY method and on-chip microscopy

KAUST Repository

Zhang, Yibo; Shin, Yoonjung; Sung, Kevin; Yang, Sam; Chen, Harrison; Wang, Hongda; Teng, Da; Rivenson, Yair; Kulkarni, Rajan P.; Ozcan, Aydogan

2017-01-01

High-throughput sectioning and optical imaging of tissue samples using traditional immunohistochemical techniques can be costly and inaccessible in resource-limited areas. We demonstrate three-dimensional (3D) imaging and phenotyping in optically transparent tissue using lens-free holographic on-chip microscopy as a low-cost, simple, and high-throughput alternative to conventional approaches. The tissue sample is passively cleared using a simplified CLARITY method and stained using 3,3′-diaminobenzidine to target cells of interest, enabling bright-field optical imaging and 3D sectioning of thick samples. The lens-free computational microscope uses pixel super-resolution and multi-height phase recovery algorithms to digitally refocus throughout the cleared tissue and obtain a 3D stack of complex-valued images of the sample, containing both phase and amplitude information. We optimized the tissue-clearing and imaging system by finding the optimal illumination wavelength, tissue thickness, sample preparation parameters, and the number of heights of the lens-free image acquisition and implemented a sparsity-based denoising algorithm to maximize the imaging volume and minimize the amount of the acquired data while also preserving the contrast-to-noise ratio of the reconstructed images. As a proof of concept, we achieved 3D imaging of neurons in a 200-μm-thick cleared mouse brain tissue over a wide field of view of 20.5 mm2. The lens-free microscope also achieved more than an order-of-magnitude reduction in raw data compared to a conventional scanning optical microscope imaging the same sample volume. Being low cost, simple, high-throughput, and data-efficient, we believe that this CLARITY-enabled computational tissue imaging technique could find numerous applications in biomedical diagnosis and research in low-resource settings.

3D imaging of optically cleared tissue using a simplified CLARITY method and on-chip microscopy

KAUST Repository

Zhang, Yibo

2017-08-12

High-throughput sectioning and optical imaging of tissue samples using traditional immunohistochemical techniques can be costly and inaccessible in resource-limited areas. We demonstrate three-dimensional (3D) imaging and phenotyping in optically transparent tissue using lens-free holographic on-chip microscopy as a low-cost, simple, and high-throughput alternative to conventional approaches. The tissue sample is passively cleared using a simplified CLARITY method and stained using 3,3′-diaminobenzidine to target cells of interest, enabling bright-field optical imaging and 3D sectioning of thick samples. The lens-free computational microscope uses pixel super-resolution and multi-height phase recovery algorithms to digitally refocus throughout the cleared tissue and obtain a 3D stack of complex-valued images of the sample, containing both phase and amplitude information. We optimized the tissue-clearing and imaging system by finding the optimal illumination wavelength, tissue thickness, sample preparation parameters, and the number of heights of the lens-free image acquisition and implemented a sparsity-based denoising algorithm to maximize the imaging volume and minimize the amount of the acquired data while also preserving the contrast-to-noise ratio of the reconstructed images. As a proof of concept, we achieved 3D imaging of neurons in a 200-μm-thick cleared mouse brain tissue over a wide field of view of 20.5 mm2. The lens-free microscope also achieved more than an order-of-magnitude reduction in raw data compared to a conventional scanning optical microscope imaging the same sample volume. Being low cost, simple, high-throughput, and data-efficient, we believe that this CLARITY-enabled computational tissue imaging technique could find numerous applications in biomedical diagnosis and research in low-resource settings.

Method for preparation of uranium hydride

International Nuclear Information System (INIS)

Gorski, M.S.; Goncalves, Miriam; Mirage, A.; Lima, W. de.

1985-01-01

A method for preparation of Uranium Hydride starting from Hidrogen and Uranium is described. In the temperature range of 250 0 up to 350 0 C, and pressures above 10torr, Hydrogen reacts smoothly with Uranium turnings forming a fine black or dark gray powder (UH 3 ). Samples containing a significant amount of oxides show a delay before the reaction begging. (Author) [pt

Electrocatalysts using porous polymers and method of preparation

Energy Technology Data Exchange (ETDEWEB)

Liu, Di-Jia; Yuan, Shengwen; Goenaga, Gabriel A.

2016-08-02

A method of producing an electrocatalyst article using porous polymers. The method creates a porous polymer designed to receive transition metal groups disposed at ligation sites and activating the transition metals to form an electrocatalyst which can be used in a fuel cell. Electrocatalysts prepared by this method are also provided. A fuel cell which includes the electrocatalyst is also provided.

Electrocatalysts using porous polymers and method of preparation

Energy Technology Data Exchange (ETDEWEB)

Liu, Di-Jia; Yuan, Shengwen; Goenaga, Gabriel A.

2015-04-21

A method of producing an electrocatalyst article using porous polymers. The method creates a porous polymer designed to receive transition metal groups disposed at ligation sites and activating the transition metals to form an electrocatalyst which can be used in a fuel cell. Electrocatalysts prepared by this method are also provided. A fuel cell which includes the electrocatalyst is also provided.

Implementation of a new rapid tissue processing method--advantages and challenges

DEFF Research Database (Denmark)

Munkholm, Julie; Talman, Maj-Lis; Hasselager, Thomas

2008-01-01

Conventional tissue processing of histologic specimens has been carried out in the same manner for many years. It is a time-consuming process involving batch production, resulting in a 1-day delay of the diagnosis. Microwave-assisted tissue processing enables a continuous high flow of histologic...... specimens through the processor with a processing time of as low as 1h. In this article, we present the effects of the automated microwave-assisted tissue processor on the histomorphologic quality and the turnaround time (TAT) for histopathology reports. We present a blind comparative study regarding...... the histomorphologic quality of microwave-processed and conventionally processed tissue samples. A total of 333 specimens were included. The microwave-assisted processing method showed a histomorphologic quality comparable to the conventional method for a number of tissue types, including skin and specimens from...

[Tissue-specific nucleoprotein complexes].

Science.gov (United States)

Riadnova, I Iu; Shataeva, L K; Khavinson, V Kh

2000-01-01

A method of isolation of native nucleorprotein complexes from cattle cerebral cortex, thymus, and liver was developed. Compositions of these complexes were studied by means of gel-chromatography and ion-exchange chromatography. These preparations were shown to consist of several fractions of proteins and their complexes differ by molecular mass and electro-chemical properties. Native nucleoprotein complexes revealed high tissue specific activity, which was not species-specific.

A new technique for Gram staining paraffin-embedded tissue.

Science.gov (United States)

Engbaek, K; Johansen, K S; Jensen, M E

1979-01-01

Five techniques for Gram staining bacteria in paraffin sections were compared on serial sections of pulmonary tissues from eight bacteriological necropsies. Brown and Hopp's method was the most satisfactory for distinguishing Gram-positive and Gram-negative bacteria. However, this method cannot be recommended as the preparations were frequently overstained, and the Gram-negative bacteria were stained indistinctly. A modification of Brown and Hopps' method was developed which stains larger numbers of Gram-negative bacteria and differentiates well between different cell types and connective tissue, and there is no risk of overstaining. PMID:86548

Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

Directory of Open Access Journals (Sweden)

Stamatović Novak

2013-01-01

Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

Electroactive Tissue Scaffolds with Aligned Pores as Instructive Platforms for Biomimetic Tissue Engineering.

Science.gov (United States)

Hardy, John G; Cornelison, R Chase; Sukhavasi, Rushi C; Saballos, Richard J; Vu, Philip; Kaplan, David L; Schmidt, Christine E

2015-01-14

Tissues in the body are hierarchically structured composite materials with tissue-specific chemical and topographical properties. Here we report the preparation of tissue scaffolds with macroscopic pores generated via the dissolution of a sacrificial supramolecular polymer-based crystal template (urea) from a biodegradable polymer-based scaffold (polycaprolactone, PCL). Furthermore, we report a method of aligning the supramolecular polymer-based crystals within the PCL, and that the dissolution of the sacrificial urea yields scaffolds with macroscopic pores that are aligned over long, clinically-relevant distances ( i.e ., centimeter scale). The pores act as topographical cues to which rat Schwann cells respond by aligning with the long axis of the pores. Generation of an interpenetrating network of polypyrrole (PPy) and poly(styrene sulfonate) (PSS) in the scaffolds yields electroactive tissue scaffolds that allow the electrical stimulation of Schwann cells cultured on the scaffolds which increases the production of nerve growth factor (NGF).

A new method of preparing single-walled carbon nanotubes

Indian Academy of Sciences (India)

A novel method of purification for single-walled carbon nanotubes, prepared by an arc-discharge method, is described. The method involves a combination of acid washing followed by high temperature hydrogen treatment to remove the metal nanoparticles and amorphous carbon present in the as-synthesized singlewalled ...

Use of focused ultrasonication in activity-based profiling of deubiquitinating enzymes in tissue.

Science.gov (United States)

Nanduri, Bindu; Shack, Leslie A; Rai, Aswathy N; Epperson, William B; Baumgartner, Wes; Schmidt, Ty B; Edelmann, Mariola J

2016-12-15

To develop a reproducible tissue lysis method that retains enzyme function for activity-based protein profiling, we compared four different methods to obtain protein extracts from bovine lung tissue: focused ultrasonication, standard sonication, mortar & pestle method, and homogenization combined with standard sonication. Focused ultrasonication and mortar & pestle methods were sufficiently effective for activity-based profiling of deubiquitinases in tissue, and focused ultrasonication also had the fastest processing time. We used focused-ultrasonicator for subsequent activity-based proteomic analysis of deubiquitinases to test the compatibility of this method in sample preparation for activity-based chemical proteomics. Copyright © 2016 Elsevier Inc. All rights reserved.

A method for quantifying mechanical properties of tissue following viral infection.

Directory of Open Access Journals (Sweden)

Vy Lam

Full Text Available Viral infection and replication involves the reorganization of the actin network within the host cell. Actin plays a central role in the mechanical properties of cells. We have demonstrated a method to quantify changes in mechanical properties of fabricated model three-dimensional (3D connective tissue following viral infection. Using this method, we have characterized the impact of infection by the human herpesvirus, cytomegalovirus (HCMV. HCMV is a member of the herpesvirus family and infects a variety of cell types including fibroblasts. In the body, fibroblasts are necessary for maintaining connective tissue and function by creating mechanical force. Using this 3D connective tissue model, we observed that infection disrupted the cell's ability to generate force and reduced the cumulative contractile force of the tissue. The addition of HCMV viral particles in the absence of both viral gene expression and DNA replication was sufficient to disrupt tissue function. We observed that alterations of the mechanical properties are, in part, due to a disruption of the underlying complex actin microfilament network established by the embedded fibroblasts. Finally, we were able to prevent HCMV-mediated disruption of tissue function by the addition of human immune globulin against HCMV. This study demonstrates a method to quantify the impact of viral infection on mechanical properties which are not evident using conventional cell culture systems.

Silica scintillating materials prepared by sol-gel methods

International Nuclear Information System (INIS)

Werst, D.W.; Sauer, M.C. Jr.; Cromack, K.R.; Lin, Y.; Tartakovsky, E.A.; Trifunac, A.D.

1993-01-01

Silica was investigated as a rad-hard alternative to organic polymer hosts for organic scintillators. Silica sol-gels were prepared by hydrolysis of tetramethoxysilane in alcohol solutions. organic dyes were incorporated into the gels by dissolving in methanol at the sol stage of gel formation. The silica sol-gel matrix is very rad-hard. The radiation stability of silica scintillators prepared by this method is dye-limited. Transient radioluminescence was measured following excitation with 30 ps pulses of 20 MeV electrons

Subperiosteal preparation using a new piezoelectric device: a histological examination

Directory of Open Access Journals (Sweden)

Stoetzer, Marcus

2014-12-01

Full Text Available Introduction: Subperiosteal preparation using a periosteal elevator leads to disturbances of local immunohistochemistry and periosteal histology due to a microtrauma. Usually soft-tissue damage can be considerably reduced by using piezoelectric technology. For this reason, the effects of a novel piezoelectric device on immunohistochemistry and periosteal histology were examined and compared to conventional preparation of the periosteum using a periosteal elevator.Material and methods: Lewis rats were randomly assigned to one of five groups (n=50. Subperiosteal preparation was performed using either a piezoelectric device or a periosteal elevator. Immunohistochemical and histological analyses were performed immediately after preparation as well as three and eight days postoperatively. A statistical analysis of the histological colouring was performed offline using analysis of variance (ANOVA on ranks (p<0.05. Results: At all times, immunohistochemical and histological analysis demonstrated a significantly more homogenous tissue structure in the group of rats that underwent piezosurgery than in the group of rats that underwent treatment with a periosteal elevator.Conclusion: The use of a piezoelectric device for subperiosteal preparation is associated with more harmonious immunohistochemical and histological results for the periosteum than the use of a conventional periosteal elevator. As a result, piezoelectric devices can be expected to have a positive effect primarily on soft tissue, in particular of the periosteal as well as on surrounding tissues.

Implementation of an office-based semen preparation method (SEP ...

African Journals Online (AJOL)

Implementation of an office-based semen preparation method (SEP-D Kit) for intra-uterine insemination (IUI): A controlled randomised study to compare the IUI pregnancy outcome between a routine (swim-up) and the SEP-D Kit method.

A method to estimate the fractional fat volume within a ROI of a breast biopsy for WAXS applications: Animal tissue evaluation

International Nuclear Information System (INIS)

Tang, Robert Y.; McDonald, Nancy; Laamanen, Curtis; LeClair, Robert J.

2014-01-01

Purpose: To develop a method to estimate the mean fractional volume of fat (ν ¯ fat ) within a region of interest (ROI) of a tissue sample for wide-angle x-ray scatter (WAXS) applications. A scatter signal from the ROI was obtained and use of ν ¯ fat in a WAXS fat subtraction model provided a way to estimate the differential linear scattering coefficient μ s of the remaining fatless tissue. Methods: The efficacy of the method was tested using animal tissue from a local butcher shop. Formalin fixed samples, 5 mm in diameter 4 mm thick, were prepared. The two main tissue types were fat and meat (fibrous). Pure as well as composite samples consisting of a mixture of the two tissue types were analyzed. For the latter samples, ν fat for the tissue columns of interest were extracted from corresponding pixels in CCD digital x-ray images using a calibration curve. The means ν ¯ fat were then calculated for use in a WAXS fat subtraction model. For the WAXS measurements, the samples were interrogated with a 2.7 mm diameter 50 kV beam and the 6° scattered photons were detected with a CdTe detector subtending a solid angle of 7.75 × 10 −5 sr. Using the scatter spectrum, an estimate of the incident spectrum, and a scatter model, μ s was determined for the tissue in the ROI. For the composite samples, a WAXS fat subtraction model was used to estimate the μ s of the fibrous tissue in the ROI. This signal was compared to μ s of fibrous tissue obtained using a pure fibrous sample. Results: For chicken and beef composites, ν ¯ fat =0.33±0.05 and 0.32 ± 0.05, respectively. The subtractions of these fat components from the WAXS composite signals provided estimates of μ s for chicken and beef fibrous tissue. The differences between the estimates and μ s of fibrous obtained with a pure sample were calculated as a function of the momentum transfer x. A t-test showed that the mean of the differences did not vary from zero in a statistically significant way thereby

Global metabolite analysis of yeast: evaluation of sample preparation methods

DEFF Research Database (Denmark)

Villas-Bôas, Silas Granato; Højer-Pedersen, Jesper; Åkesson, Mats Fredrik

2005-01-01

Sample preparation is considered one of the limiting steps in microbial metabolome analysis. Eukaryotes and prokaryotes behave very differently during the several steps of classical sample preparation methods for analysis of metabolites. Even within the eukaryote kingdom there is a vast diversity...

Applications and Preparation Methods of Copper Chromite Catalysts: A Review

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Ram Prasad

2011-11-01

Full Text Available In this review article various applications and preparation methods of copper chromite catalysts have been discussed. While discussing it is concluded that copper chromite is a versatile catalyst which not only catalyses numerous processes of commercial importance and national program related to defence and space research but also finds applications in the most concerned problem worldwide i.e. environmental pollution control. Several other very useful applications of copper chromite catalysts are in production of clean energy, drugs and agro chemicals, etc. Various preparation methods about 15 have been discussed which depicts clear idea about the dependence of catalytic activity and selectivity on way of preparation of catalyst. In view of the globally increasing interest towards copper chromite catalysis, reexamination on the important applications of such catalysts and their useful preparation methods is thus the need of the time. This review paper encloses 369 references including a well-conceivable tabulation of the newer state of the art. Copyright © 2011 by BCREC UNDIP. All rights reserved.(Received: 19th March 2011, Revised: 03rd May 2011, Accepted: 23rd May 2011[How to Cite: R. Prasad, and P. Singh. (2011. Applications and Preparation Methods of Copper Chromite Catalysts: A Review. Bulletin of Chemical Reaction Engineering & Catalysis, 6 (2: 63-113. doi:10.9767/bcrec.6.2.829.63-113][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.2.829.63-113 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/829 ] | View in 

Sample preparation method for scanning force microscopy

CERN Document Server

Jankov, I R; Szente, R N; Carreno, M N P; Swart, J W; Landers, R

2001-01-01

We present a method of sample preparation for studies of ion implantation on metal surfaces. The method, employing a mechanical mask, is specially adapted for samples analysed by Scanning Force Microscopy. It was successfully tested on polycrystalline copper substrates implanted with phosphorus ions at an acceleration voltage of 39 keV. The changes of the electrical properties of the surface were measured by Kelvin Probe Force Microscopy and the surface composition was analysed by Auger Electron Spectroscopy.

Review of Research on Template Methods in Preparation of Nanomaterials

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Yadian Xie

2016-01-01

Full Text Available The nanomaterials have been widely used in various fields, such as photonics, catalysis, and adsorption, because of their unique physical and chemical properties. Therefore, their production methods are of utmost importance. Compared with traditional synthetic methods, the template method can effectively control the morphology, particle size, and structure during the preparation of nanomaterials, which is an effective method for their synthesis. The key for the template method is to choose different templates, which are divided into hard template and soft template according to their different structures. In this paper, the effects of different types of templates on the morphology of nanomaterials during their preparation are investigated from two aspects: hard template and soft template, combined with the mechanism of action.

Preparation and characterization of gelatin–hydroxyapatite composite microspheres for hard tissue repair

International Nuclear Information System (INIS)

Chao, Shao Ching; Wang, Ming-Jia; Pai, Nai-Su; Yen, Shiow-Kang

2015-01-01

Gelatin–hydroxyapatite composite microspheres composed of 21% gelatin (G) and 79% hydroxyapatite (HA) with uniform morphology and controllable size were synthesized from a mixed solution of Ca(NO 3 ) 2 , NH 4 H 2 PO 4 and gelatin by a wet-chemical method. Material analyses such as X-ray diffraction (XRD), scanning/transmission electron microscopy examination (SEM/TEM) and inductively coupled plasma-mass spectroscopy (ICP-MS) were used to characterize G–HA microspheres by analyzing their crystalline phase, microstructure, morphology and composition. HA crystals precipitate along G fibers to form nano-rods with diameters of 6–10 nm and tangle into porous microspheres after blending. The cell culture indicates that G–HA composite microspheres without any toxicity could enhance the proliferation and differentiation of osteoblast-like cells. In a rat calvarial defect model, G–HA bioactive scaffolds were compared with fibrin glue (F) and Osteoset® Bone Graft Substitute (OS) for their capacity of regenerating bone. Four weeks post-implantation, new bone, mineralization, and expanded blood vessel area were found in G–HA scaffolds, indicating greater osteoconductivity and bioactivity than F and OS. - Highlights: • G–HA composite microspheres were prepared by hydroxyapatite and gelatin. • In vitro tests indicated that the G–HA microspheres were biocompatible and bioactive. • In in vitro tests, G–HA microspheres could be applied in hard tissue engineering. • G–HA had healed the bone defect and provides a high proportion of surface area to open space

Methods of preparing deposits containing iron oxides for recycling

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T. Lis

2013-04-01

Full Text Available The metallurgical industry is one of the largest sources of wastes. Some of them, however, owing to their content of metals such as zinc or iron, may become valuable secondary raw materials. In order to achieve that purpose, they require appropriate preparation. This article provides a discussion on the methods of preparation of scrap from steelworks, namely deposits containing iron oxides, enabling their recycling.

A comparison between the dimensions of positive transtibial residual limb molds prepared by air pressure casting and weight-bearing casting methods.

Science.gov (United States)

Hajiaghaei, Behnam; Ebrahimi, Ismail; Kamyab, Mojtaba; Saeedi, Hassan; Jalali, Maryam

2016-01-01

Creating a socket with proper fit is an important factor to ensure the comfort and control of prosthetic devices. Several techniques are commonly used to cast transtibial stumps but their effect on stump shape deformation is not well understood. This study compares the dimensions, circumferences and volumes of the positive casts and also the socket comfort between two casting methods. Our hypothesis was that the casts prepared by air pressure method have less volume and are more comfortable than those prepared by weight bearing method. Fifteen transtibial unilateral amputees participated in the study. Two weight bearing and air pressure casting methods were utilized for their residual limbs. The diameters and circumferences of various areas of the residual limbs and positive casts were compared. The volumes of two types of casts were measured by a volumeter and compared. Visual Analogue Scale (VAS) was used to measure the sockets fit comfort. Circumferences at 10 and 15 cm below the patella on the casts were significantly smaller in air pressure casting method compared to the weight bearing method (p=0.00 and 0.01 respectively). The volume of the cast in air pressure method was lower than that of the weight bearing method (p=0.006). The amputees found the fit of the sockets prepared by air pressure method more comfortable than the weight bearing sockets (p=0.015). The air pressure casting reduced the circumferences of the distal portion of residual limbs which has more soft tissue and because of its snug fit it provided more comfort for amputees, according to the VAS measurements.

Electroactive Tissue Scaffolds with Aligned Pores as Instructive Platforms for Biomimetic Tissue Engineering

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John G. Hardy

2015-01-01

Full Text Available Tissues in the body are hierarchically structured composite materials with tissue-specific chemical and topographical properties. Here we report the preparation of tissue scaffolds with macroscopic pores generated via the dissolution of a sacrificial supramolecular polymer-based crystal template (urea from a biodegradable polymer-based scaffold (polycaprolactone, PCL. Furthermore, we report a method of aligning the supramolecular polymer-based crystals within the PCL, and that the dissolution of the sacrificial urea yields scaffolds with macroscopic pores that are aligned over long, clinically-relevant distances (i.e., centimeter scale. The pores act as topographical cues to which rat Schwann cells respond by aligning with the long axis of the pores. Generation of an interpenetrating network of polypyrrole (PPy and poly(styrene sulfonate (PSS in the scaffolds yields electroactive tissue scaffolds that allow the electrical stimulation of Schwann cells cultured on the scaffolds which increases the production of nerve growth factor (NGF.

Preparation and Characterization of Polycaprolactone / Layered Double Hydroxide Nanocomposite for Hard Tissue Engineering Applications

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M. Baradaran

2016-12-01

Full Text Available In recent years the use of nanomaterials in bone tissue engineering scaffold has been considered due to its imitating the structure of natural bone tissue which contains a nanocomposite structure mixed with a three-dimensional matrix. In the meantime, Polycaprol actone has been used as a bio-polymer in bone tissue engineering applications as a scaffold. The aim of this study is to develop porous scaffolds made of polycaprol actone/layered double hydroxide biocomposite, with appropriate mechanical, bioactive and biological properties, for bone tissue engineering application. The nanocomposite scaffolds were fabricated by the particulate leaching method and freeze-drying method. In this study, MG63 cells (osteosarcoma was investigated for cellular study. Energy dispersive X-ray analysis confirmed uniform distribution of ceramic phase in polycaprol actone matrix. The results of mechanical tests showed the increase in young’s modulus after addition of ceramic phase. The microscopic investigations demonstrated that the pores generated after addition of ceramic phase and the average size of pores was as large as 100-600μm. Also by the addition of LDH, the hydrophilicity of PCL increased but the rate of hydroxyapatite formation was delayed due to presence of magnesium ions. The cell culture experiments confirmed the attachment and proliferation of cells on the scaffolds. The results showed that the fabricated scaffolds have the potential to be used in cancellous bone tissue engineering.

Preparation of red phosphor (Y, Gd)BO3:Eu by soft chemistry methods

International Nuclear Information System (INIS)

Cui Xiangzhong; Zhuang Weidong; Yu Zhijian; Xia Tian; Huang Xiaowei; Li Hongwei

2008-01-01

The three soft chemistry methods were employed to prepare the red phosphor (Y, Gd)BO 3 :Eu, such as coprecipitation-combustion method, salt assisted combustion method and emulsion method. The main factors affecting particle size, particle distribution and luminescent properties of the product were investigated in detail, and as a result, the preparation processes were optimized. The phosphors were characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), transmission electronic microscope (TEM) and vacuum ultraviolet (VUV) spectra. Results reveal that phosphors with different morphology, small particle size and high luminescence intensity could be obtained by soft chemistry methods. The difference between the luminescence properties of phosphors in this work and commercial rare earth borate phosphor is discussed. The phosphor with grain shape and high luminescence intensity could be prepared by coprecipitation-combustion method, nanophosphor could be prepared by salt assisted combustion method, and spherical phosphor with a narrow size distribution could be obtained by using emulsion method

A Systematic Review of Autologous Platelet-Rich Plasma and Fat Graft Preparation Methods.

Science.gov (United States)

Luck, Joshua; Smith, Oliver J; Mosahebi, Afshin

2017-12-01

The addition of platelet-rich plasma (PRP) to adipose tissue may improve fat graft survival, although graft retention rates vary markedly between studies. To what extent this outcome heterogeneity reflects differing methodological factors remains unknown. This systematic review aims to synthesize and critically review methodological approaches to autologous PRP and fat cotransplantation in both human and animal studies. In accordance with PRISMA guidelines, Ovid MEDLINE, Scopus, and Cochrane Library databases were searched from inception to April 2017. Data were extracted from all in vivo studies involving autologous PRP and fat cotransplantation. A secondary aim was to assess reporting of technical detail; authors were not contacted to provide missing data. From 335 articles, 23 studies were included in the qualitative synthesis. Some 21 were performed in humans and 2 in rabbits. Six studies were randomized control trials; the remainder reported on observational data. Methods of PRP extraction and activation varied markedly between studies. Fat graft preparation was comparatively more consistent. Methods of PRP and fat mixing differed significantly, especially with regards to relative volume/volume ratios. Our study represents the first systematic review of methodological factors in autologous PRP and fat cotransplantation. It demonstrates that technical factors in graft preparation and administration vary significantly between in vivo studies. Such methodological heterogeneity may explain observed differences in experimental and clinical outcomes. Reporting of key procedural information is inconsistent and often inadequate. These issues make meaningful evaluation of the PRP-enhanced fat grafting literature difficult and may limit its translation into clinical practice.

Preparation of polymeric biomaterials with the aid of radiation-chemical methods

International Nuclear Information System (INIS)

Kabanov, Vitalii Ya

1998-01-01

The results of the application of radiation-chemical methods for the preparation of polymeric biomaterials are surveyed and treated systematically. The characteristic features of these methods and their advantages and disadvantages are indicated. The properties of polymeric biomaterials prepared using ionising radiation are examined. Particular attention is devoted to studies carried out during the last 10-15 years. The bibliography includes 492 references.

Method for preparing a sinterable uranium dioxide powder

International Nuclear Information System (INIS)

Thornton, T.A.; Holaday, V.D. Jr.

1985-01-01

This invention provides an improved method for preparing a sinterable uranium dioxide powder for the preparation of nuclear fuel, using microwave radiation in a microwave induction furnace. The starting compound may be uranyl nitrate hexahydrate, ammonium diuranate or ammonium uranyl carbonate. The starting compound is heated in a microwave induction furnace for a period of time sufficient for compound decomposition. The decomposed compound is heated in a microwave induction furnace in a reducing atmosphere for a period of time sufficient to reduce the decomposed compound to uranium dioxide powder

A practical method for target preparation of powdered materials

International Nuclear Information System (INIS)

Sugai, Isao.

1977-01-01

This is the sixth report on the practical method of target preparation for use in nuclear physics experiments following the previous one (INS-TL-131, 1976). We have made various targets by developing the centrifugal precipitation method, which is particularly effective in the cases; (a) metal with high melting point and low vapor pressure, (b) oxides which are difficult to prepare by the usual vacuum evaporation technique and (c) some enriched isotopes which are very minute in quantity (less than - 10 mg) and low in recovery ratio. The samples were once suspended in liquid paraffin by ultrasonic wave vibrator, and then centrifugally precipitated on a thin backing foil such as Mylar or aluminum set and the bottom of the centrifugal tube. Uniformity of target made in this way was checked by an 24 Am-α ray thickness gauge. Contaminations smudged in the preparing process were checked by irradiating the targets with the proton beam from the FM Cyclotron at I.N.S. (auth.)

Liquid scintillation: Sample preparation and counting atypical emissions

International Nuclear Information System (INIS)

Anon.

1991-01-01

Liquid scintillation sample preparation has the most published information but the least amount of definitive technical direction because the chemical and physical nature of the samples from biological investigations varies widely. This chapter discusses the following related topics: Aqueous Samples; Tissue Solubilizers; Absorption of 14 CO 2 ; Sample Combustion Methods; Heterogeneous Systems; Sample Preparation Problems (colored samples, chemiluminescence, photoluminescence, static electricity); Counting Various Types of Emitters; Counting Atypical Emissions. 2 refs., 2 figs

A Method for Microalgae Proteomics Analysis Based on Modified Filter-Aided Sample Preparation.

Science.gov (United States)

Li, Song; Cao, Xupeng; Wang, Yan; Zhu, Zhen; Zhang, Haowei; Xue, Song; Tian, Jing

2017-11-01

With the fast development of microalgal biofuel researches, the proteomics studies of microalgae increased quickly. A filter-aided sample preparation (FASP) method is widely used proteomics sample preparation method since 2009. Here, a method of microalgae proteomics analysis based on modified filter-aided sample preparation (mFASP) was described to meet the characteristics of microalgae cells and eliminate the error caused by over-alkylation. Using Chlamydomonas reinhardtii as the model, the prepared sample was tested by standard LC-MS/MS and compared with the previous reports. The results showed mFASP is suitable for most of occasions of microalgae proteomics studies.

Compositions, antibodies, asthma diagnosis methods, and methods for preparing antibodies

Energy Technology Data Exchange (ETDEWEB)

Jin, Hongjun; Zangar, Richard C.

2017-01-17

Methods for preparing an antibody are provided with the method including incorporating 3-bromo-4-hydroxy-benzoic acid into a protein to form an antigen, immunizing a mammalian host with the antigen, and recovering an antibody having an affinity for the antigen from the host. Antibodies having a binding affinity for a monohalotyrosine are provided as well as composition comprising an antibody bound with monohalotyrosine. Compositions comprising a protein having a 3-bromo-4-hydroxy-benzoic acid moiety are also provided. Methods for evaluating the severity of asthma are provide with the methods including analyzing sputum of a patient using an antibody having a binding affinity for monohalotyrosine, and measuring the amount of antibody bound to protein. Methods for determining eosinophil activity in bodily fluid are also provided with the methods including exposing bodily fluid to an antibody having a binding affinity for monohalotyrosine, and measuring the amount of bound antibody to determine the eosinophil activity.

Soft tissue deformation estimation by spatio-temporal Kalman filter finite element method.

Science.gov (United States)

Yarahmadian, Mehran; Zhong, Yongmin; Gu, Chengfan; Shin, Jaehyun

2018-01-01

Soft tissue modeling plays an important role in the development of surgical training simulators as well as in robot-assisted minimally invasive surgeries. It has been known that while the traditional Finite Element Method (FEM) promises the accurate modeling of soft tissue deformation, it still suffers from a slow computational process. This paper presents a Kalman filter finite element method to model soft tissue deformation in real time without sacrificing the traditional FEM accuracy. The proposed method employs the FEM equilibrium equation and formulates it as a filtering process to estimate soft tissue behavior using real-time measurement data. The model is temporally discretized using the Newmark method and further formulated as the system state equation. Simulation results demonstrate that the computational time of KF-FEM is approximately 10 times shorter than the traditional FEM and it is still as accurate as the traditional FEM. The normalized root-mean-square error of the proposed KF-FEM in reference to the traditional FEM is computed as 0.0116. It is concluded that the proposed method significantly improves the computational performance of the traditional FEM without sacrificing FEM accuracy. The proposed method also filters noises involved in system state and measurement data.

Optimal molecular profiling of tissue and tissue components: defining the best processing and microdissection methods for biomedical applications.

Science.gov (United States)

Rodriguez-Canales, Jaime; Hanson, Jeffrey C; Hipp, Jason D; Balis, Ulysses J; Tangrea, Michael A; Emmert-Buck, Michael R; Bova, G Steven

2013-01-01

Isolation of well-preserved pure cell populations is a prerequisite for sound studies of the molecular basis of any tissue-based biological phenomenon. This updated chapter reviews current methods for obtaining anatomically specific signals from molecules isolated from tissues, a basic requirement for productive linking of phenotype and genotype. The quality of samples isolated from tissue and used for molecular analysis is often glossed over or omitted from publications, making interpretation and replication of data difficult or impossible. Fortunately, recently developed techniques allow life scientists to better document and control the quality of samples used for a given assay, creating a foundation for improvement in this area. Tissue processing for molecular studies usually involves some or all of the following steps: tissue collection, gross dissection/identification, fixation, processing/embedding, storage/archiving, sectioning, staining, microdissection/annotation, and pure analyte labeling/identification and quantification. We provide a detailed comparison of some current tissue microdissection technologies and provide detailed example protocols for tissue component handling upstream and downstream from microdissection. We also discuss some of the physical and chemical issues related to optimal tissue processing and include methods specific to cytology specimens. We encourage each laboratory to use these as a starting point for optimization of their overall process of moving from collected tissue to high-quality, appropriately anatomically tagged scientific results. Improvement in this area will significantly increase life science quality and productivity. The chapter is divided into introduction, materials, protocols, and notes subheadings. Because many protocols are covered in each of these sections, information relating to a single protocol is not contiguous. To get the greatest benefit from this chapter, readers are advised to read through the entire

Comparison between properties of polyurethane nano composites prepared by two different methods

International Nuclear Information System (INIS)

Barmar, M.; Barikani, M.; Fereidoonnia, M.

2009-01-01

In this work, a thermoplastic polyurethane elastomer model based on polytetramethylene glycol. toluene diisocyanate and 1,4-butanediol was selected and synthesized. According to this model two types of polyurethane nano composites were prepared by in situ polymerization and melt intercalation procedures. The organo-modified nano clay was used in nano composites samples in 0.4 weight percent level. The prepared nano composites were studied by WAXD, tensile and thermal analysis. Thermal properties of the nano composites were higher than those of pure polyurethane elastomers. Nano composites prepared via melt intercalation method showed a lower tensile strength and hardness than those prepared through in situ polymerization method

Effect of MELT method on thoracolumbar connective tissue: The full study.

Science.gov (United States)

Sanjana, Faria; Chaudhry, Hans; Findley, Thomas

2017-01-01

Altered connective tissue structure has been identified in adults with chronic low back pain (LBP). A self-care treatment for managing LBP is the MELT method. The MELT method is a hands-off, self-treatment that is said to alleviate chronic pain, release tension and restore mobility, utilizing specialized soft treatments balls, soft body roller and techniques mimicking manual therapy. The objective of this study was to determine whether thickness of thoracolumbar connective tissue and biomechanical and viscoelastic properties of myofascial tissue in the low back region change in subjects with chronic LBP as a result of MELT. This study was designed using a quasi experimental pre-post- design that analyzed data from subjects who performed MELT. Using ultrasound imaging and an algorithm developed in MATLAB, thickness of thoracolumbar connective tissue was analyzed in 22 subjects. A hand-held digital palpation device, called the MyotonPRO, was used to assess biomechanical properties such as stiffness, elasticity, tone and mechanical stress relaxation time of the thoracolumbar myofascial tissue. A forward bending test assessing flexibility and pain scale was added to see if MELT affected subjects with chronic LBP. A significant decrease in connective tissue thickness and pain was observed in participants. Significant increase in flexibility was also recorded. Copyright © 2016 Elsevier Ltd. All rights reserved.

A method to estimate the fractional fat volume within a ROI of a breast biopsy for WAXS applications: Animal tissue evaluation

Energy Technology Data Exchange (ETDEWEB)

Tang, Robert Y., E-mail: rx-tang@laurentian.ca [Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); McDonald, Nancy, E-mail: mcdnancye@gmail.com; Laamanen, Curtis, E-mail: cx-laamanen@laurentian.ca [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); LeClair, Robert J., E-mail: rleclair@laurentian.ca [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6, Canada and Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada)

2014-11-01

Purpose: To develop a method to estimate the mean fractional volume of fat (ν{sup ¯}{sub fat}) within a region of interest (ROI) of a tissue sample for wide-angle x-ray scatter (WAXS) applications. A scatter signal from the ROI was obtained and use of ν{sup ¯}{sub fat} in a WAXS fat subtraction model provided a way to estimate the differential linear scattering coefficient μ{sub s} of the remaining fatless tissue. Methods: The efficacy of the method was tested using animal tissue from a local butcher shop. Formalin fixed samples, 5 mm in diameter 4 mm thick, were prepared. The two main tissue types were fat and meat (fibrous). Pure as well as composite samples consisting of a mixture of the two tissue types were analyzed. For the latter samples, ν{sub fat} for the tissue columns of interest were extracted from corresponding pixels in CCD digital x-ray images using a calibration curve. The means ν{sup ¯}{sub fat} were then calculated for use in a WAXS fat subtraction model. For the WAXS measurements, the samples were interrogated with a 2.7 mm diameter 50 kV beam and the 6° scattered photons were detected with a CdTe detector subtending a solid angle of 7.75 × 10{sup −5} sr. Using the scatter spectrum, an estimate of the incident spectrum, and a scatter model, μ{sub s} was determined for the tissue in the ROI. For the composite samples, a WAXS fat subtraction model was used to estimate the μ{sub s} of the fibrous tissue in the ROI. This signal was compared to μ{sub s} of fibrous tissue obtained using a pure fibrous sample. Results: For chicken and beef composites, ν{sup ¯}{sub fat}=0.33±0.05 and 0.32 ± 0.05, respectively. The subtractions of these fat components from the WAXS composite signals provided estimates of μ{sub s} for chicken and beef fibrous tissue. The differences between the estimates and μ{sub s} of fibrous obtained with a pure sample were calculated as a function of the momentum transfer x. A t-test showed that the mean of the

Numerical study of water diffusion in biological tissues using an improved finite difference method

International Nuclear Information System (INIS)

Xu Junzhong; Does, Mark D; Gore, John C

2007-01-01

An improved finite difference (FD) method has been developed in order to calculate the behaviour of the nuclear magnetic resonance signal variations caused by water diffusion in biological tissues more accurately and efficiently. The algorithm converts the conventional image-based finite difference method into a convenient matrix-based approach and includes a revised periodic boundary condition which eliminates the edge effects caused by artificial boundaries in conventional FD methods. Simulated results for some modelled tissues are consistent with analytical solutions for commonly used diffusion-weighted pulse sequences, whereas the improved FD method shows improved efficiency and accuracy. A tightly coupled parallel computing approach was also developed to implement the FD methods to enable large-scale simulations of realistic biological tissues. The potential applications of the improved FD method for understanding diffusion in tissues are also discussed. (note)

Methods for preparing synthetic freshwaters.

Science.gov (United States)

Smith, E J; Davison, W; Hamilton-Taylor, J

2002-03-01

Synthetic solutions that emulate the major ion compositions of natural waters are useful in experiments aimed at understanding biogeochemical processes. Standard recipes exist for preparing synthetic analogues of seawater, with its relatively constant composition, but, due to the diversity of freshwaters, a range of compositions and recipes is required. Generic protocols are developed for preparing synthetic freshwaters of any desired composition. The major problems encountered in preparing hard and soft waters include dissolving sparingly soluble calcium carbonate, ensuring that the ionic components of each concentrated stock solution cannot form an insoluble salt and dealing with the supersaturation of calcium carbonate in many hard waters. For acidic waters the poor solubility of aluminium salts requires attention. These problems are overcome by preparing concentrated stock solutions according to carefully designed reaction paths that were tested using a combination of experiment and equilibrium modeling. These stock solutions must then be added in a prescribed order to prepare a final solution that is brought into equilibrium with the atmosphere. The example calculations for preparing hard, soft and acidic freshwater surrogates with major ion compositions the same as published analyses, are presented in a generalized fashion that should allow preparation of any synthetic freshwater according to its known analysis.

A high-resolution method for the localization of proanthocyanidins in plant tissues

Directory of Open Access Journals (Sweden)

Panter Stephen

2011-05-01

Full Text Available Abstract Background Histochemical staining of plant tissues with 4-dimethylaminocinnamaldehyde (DMACA or vanillin-HCl is widely used to characterize spatial patterns of proanthocyanidin accumulation in plant tissues. These methods are limited in their ability to allow high-resolution imaging of proanthocyanidin deposits. Results Tissue embedding techniques were used in combination with DMACA staining to analyze the accumulation of proanthocyanidins in Lotus corniculatus (L. and Trifolium repens (L. tissues. Embedding of plant tissues in LR White or paraffin matrices, with or without DMACA staining, preserved the physical integrity of the plant tissues, allowing high-resolution imaging that facilitated cell-specific localization of proanthocyanidins. A brown coloration was seen in proanthocyanidin-producing cells when plant tissues were embedded without DMACA staining and this was likely to have been due to non-enzymatic oxidation of proanthocyanidins and the formation of colored semiquinones and quinones. Conclusions This paper presents a simple, high-resolution method for analysis of proanthocyanidin accumulation in organs, tissues and cells of two plant species with different patterns of proanthocyanidin accumulation, namely Lotus corniculatus (birdsfoot trefoil and Trifolium repens (white clover. This technique was used to characterize cell type-specific patterns of proanthocyanidin accumulation in white clover flowers at different stages of development.

Preparation of A-150 tissue-equivalent plastic films

International Nuclear Information System (INIS)

Saion, E.B.; Shaari, A.H.; Watt, D.E.

1992-01-01

A-150 tissue-equivalent (TE) plastic is widely used as a wall material for tissue-equivalent proportional counters (TEPCS) used in experimental microdosimetry. The objective of this note is to give a technical account of how A-150 TE plastic film can be fabricated in the laboratory from commercially available A-150 TE plastic. (author)

A Proteomics Sample Preparation Method for Mature, Recalcitrant Leaves of Perennial Plants

Science.gov (United States)

Na, Zhang; Chengying, Lao; Bo, Wang; Dingxiang, Peng; Lijun, Liu

2014-01-01

Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie). An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants. PMID:25028960

A proteomics sample preparation method for mature, recalcitrant leaves of perennial plants.

Directory of Open Access Journals (Sweden)

Deng Gang

Full Text Available Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie. An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants.

Methods of thallium-201 preparation from proton irradiated thallium targets

International Nuclear Information System (INIS)

Kozlova, M.D.; Sevast'yanova, A.S.; Malinin, A.B.; Kurenkov, N.V.

1989-01-01

Two methods of thallium-201 preparation from Tl-targets irradiated by protons: oxidation-extraction (1) and extraction (2) - are developed. At first radioactive lead is separated from the target material - thallium macroquantities during ∼32 hours, then thallium-201 was separated from residual activity of lead radioisotopes and transformed it into the necessary chemical formula. The 1st and 2nd methods differ from each other by the 1st stage of target retreatment; only extraction was used to separate radioactive lead in the 2nd method. The target was solved in H 2 SO 4 . The 1st method permits to separate thallium-201 with chemical yield not less than 90 %, the 2nd one - higher than 95 %. Volumetric activity of thallium-201 prepared is more than 55 MBq/ml. 5 refs

Formulation and method for preparing gels comprising hydrous aluminum oxide

Science.gov (United States)

Collins, Jack L.

2014-06-17

Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

Subperiosteal preparation using a new piezoelectric device: a histological examination

OpenAIRE

Stoetzer, Marcus; Magel, Anja; Kampmann, Andreas; Lemound, Juliana; Gellrich, Nils-Claudius; von See, Constantin

2014-01-01

Introduction: Subperiosteal preparation using a periosteal elevator leads to disturbances of local immunohistochemistry and periosteal histology due to a microtrauma. Usually soft-tissue damage can be considerably reduced by using piezoelectric technology. For this reason, the effects of a novel piezoelectric device on immunohistochemistry and periosteal histology were examined and compared to conventional preparation of the periosteum using a periosteal elevator.Material and methods: Lewis...

Polymeric nanoparticles: A study on the preparation variables and characterization methods.

Science.gov (United States)

Crucho, Carina I C; Barros, Maria Teresa

2017-11-01

Since the emergence of Nanotechnology in the past decades, the development and design of nanomaterials has become an important field of research. An emerging component in this field is nanomedicine, wherein nanoscale materials are being developed for use as imaging agents or for drug delivery applications. Much work is currently focused in the preparation of well-defined nanomaterials in terms of size and shape. These factors play a significantly role in the nanomaterial behavior in vivo. In this context, this review focuses on the toolbox of available methods for the preparation of polymeric nanoparticles. We highlight some recent examples from the literature that demonstrate the influence of the preparation method on the physicochemical characteristics of the nanoparticles. Additionally, in the second part, the characterization methods for this type of nanoparticles are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation and characterization of gelatin–hydroxyapatite composite microspheres for hard tissue repair

Energy Technology Data Exchange (ETDEWEB)

Chao, Shao Ching [Department of Materials Science and Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung 40227, Taiwan (China); Department of Minimally Invasive Skull Neurosurgery, Neurological Institute, Taichung Veterans General Hospital, 1650 Taiwan Boulevard, Sect. 4, Taichung, Taiwan (China); Department of Neurosurgery, ChangHua Hospital, Ministry of Health and Welfare, 80 Chung Cheng Road, Sect. 2 Chiu Kuan Village, Changhua 500, Taiwan (China); Wang, Ming-Jia; Pai, Nai-Su [Department of Materials Science and Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung 40227, Taiwan (China); Yen, Shiow-Kang, E-mail: skyen@dragon.nchu.edu.tw [Department of Materials Science and Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung 40227, Taiwan (China)

2015-12-01

Gelatin–hydroxyapatite composite microspheres composed of 21% gelatin (G) and 79% hydroxyapatite (HA) with uniform morphology and controllable size were synthesized from a mixed solution of Ca(NO{sub 3}){sub 2}, NH{sub 4}H{sub 2}PO{sub 4} and gelatin by a wet-chemical method. Material analyses such as X-ray diffraction (XRD), scanning/transmission electron microscopy examination (SEM/TEM) and inductively coupled plasma-mass spectroscopy (ICP-MS) were used to characterize G–HA microspheres by analyzing their crystalline phase, microstructure, morphology and composition. HA crystals precipitate along G fibers to form nano-rods with diameters of 6–10 nm and tangle into porous microspheres after blending. The cell culture indicates that G–HA composite microspheres without any toxicity could enhance the proliferation and differentiation of osteoblast-like cells. In a rat calvarial defect model, G–HA bioactive scaffolds were compared with fibrin glue (F) and Osteoset® Bone Graft Substitute (OS) for their capacity of regenerating bone. Four weeks post-implantation, new bone, mineralization, and expanded blood vessel area were found in G–HA scaffolds, indicating greater osteoconductivity and bioactivity than F and OS. - Highlights: • G–HA composite microspheres were prepared by hydroxyapatite and gelatin. • In vitro tests indicated that the G–HA microspheres were biocompatible and bioactive. • In in vitro tests, G–HA microspheres could be applied in hard tissue engineering. • G–HA had healed the bone defect and provides a high proportion of surface area to open space.

Influence of preparation method on structural and magnetic ...

Indian Academy of Sciences (India)

Administrator

Influence of preparation method on structural and magnetic properties of nickel ferrite nanoparticles. BINU P JACOB, ASHOK KUMAR†, R P PANT†, SUKHVIR SINGH† and. E M MOHAMMED*. Department of Physics, Maharaja's College, Ernakulam 681 011, India. †National Physical Laboratory, New Delhi 110 012, India.

Preparation of biodegradable PLA/PLGA membranes with PGA mesh and their application for periodontal guided tissue regeneration

Energy Technology Data Exchange (ETDEWEB)

Kim, Eun Jin; Kang, Inn-Kyu [Department of Polymer Science, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu 702-701 (Korea, Republic of); Yoon, Suk Joon [Department of Biology, Sookmyung Women' s University, Hyochangwongil 52, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Yeo, Guw-Dong; Pai, Chaul-Min, E-mail: ikkang@knu.ac.k [Samyang Central R and D Center, 63-2 Hwaam-dong, Yusung-gu, Daejeon 305-717 (Korea, Republic of)

2009-10-15

A biodegradable polylactic acid (PLA)/poly(glycolide-co-lactide) copolymer (PLGA) membrane with polyglycolic acid (PGA) mesh was prepared to aid the effective regeneration of defective periodontal tissues. The microporous membrane used in this study consists of biodegradable polymers, and seems to have a structure to provide appropriate properties for periodontal tissue regeneration. Based on the albumin permeation test, it is known that the biodegradable membrane exhibits the suitable permeability of nutrients. The membrane maintained its physical integrity for 6-8 weeks, which could be sufficient to retain space in the periodontal pocket. Cell attachment and cytotoxicity tests were performed with respect to the evaluation of biocompatibility of the membrane. As a result, the membrane did not show any cytotoxicity. The safety and therapeutic efficacies of the biodegradable membranes were confirmed in animal tests.

Dentine microhardness after different methods for detection and removal of carious dentine tissue

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Fernanda Brandão Mollica

2012-08-01

Full Text Available There are several methods for identifying carious dentinal tissue aiming to avoid removal of healthy dentinal tissue. OBJECTIVES: The purpose of this study was to test different methods for the detection of carious dentinal tissue regarding the amount of carious tissue removed and the remaining dentin microhardness after caries removal. MATERIAL AND METHODS: The dentin surfaces of 20 bovine teeth were exposed and half of the surface was protected with nail polish. Cariogenic challenge was performed by immersion in a demineralizing solution for 14 days. After transverse cross-section of the crown, the specimens were divided into four groups (n=10, according to the method used to identify and remove the carious tissue: "Papacárie", Caries-detector dye, DIAGNOdent and Tactile method. After caries removal, the cross-sectional surface was included in acrylic resin and polished. In a microhardness tester, the removed dentin thickness and the Vickers microhardness of the following regions were evaluated: remaining dentin after caries removal and superficial and deep healthy dentin. RESULTS: ANOVA and Tukey's test (α=0.05 were performed, except for DIAGNOdent, which did not detect the presence of caries. Results for removed dentin thickness were: "Papacárie" (424.7±105.0; a, Caries-detector dye (370.5±78.3; ab, Tactile method (322.8±51.5; bc. Results for the remaining dentin microhardness were: "Papacárie" (42.2±10.5; bc, Caries-detector dye (44.6±11.8; abc, Tactile method (24.3±9.0; d. CONCLUSIONS: DIAGNOdent did not detect the presence of carious tissue; Tactile method and "Papacárie" resulted in the least and the most dentinal thickness removal, respectively; Tactile method differed significantly from "Papacárie" and Caries-detector dye in terms of the remaining dentin microhardness, and Tactile method was the one which presented the lowest microhardness values.

Evaluation of preparation methods for MS-based analysis of intestinal epithelial cell proteomes

DEFF Research Database (Denmark)

Hesselager, Marianne Overgaard; Codrea, Marius Cosmin; Bendixen, Emøke

2015-01-01

analyzed by LC and electrospray QTOF-MS. The methods were evaluated according to efficiency, purity, transmembrane protein recovery, as well as for suitability to large-scale preparations. Our data clearly demonstrate that mucosal shaving is by far the best-suited method for in-depth MS analysis in terms...... are low in abundance, and large amounts of sample is needed for their preparation and for undertaking MS-based analysis. The aim of this study was to evaluate three different methods for isolation and preparation of pig intestinal epithelial cells for MS-based analysis of the proteome. Samples were...... of ease and speed of sample preparation, as well as protein recovery. In comparison, more gentle methods where intestinal epithelial cells are harvested by shaking are more time consuming, result in lower protein yield, and are prone to increased technical variation due to multiple steps involved....

Trace element load in cancer and normal lung tissue

International Nuclear Information System (INIS)

Kubala-Kukus, A.; Braziewicz, J.; Banas, D.; Majewska, U.; Gozdz, S.; Urbaniak, A.

1999-01-01

Samples of malignant and benign human lung tissues were analysed by two complementary methods, i.e., particle induced X-ray emission (PIXE) and total reflection X-ray fluorescence (TRXRF). The concentration of trace elements of P, S, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, Se, Sr, Hg and Pb was determined in squamous cancer of lung tissue from 65 people and in the benign lung tumour tissue from 5 people. Several elements shows enhancement in cancerous lung tissue of women in comparison to men, i.e., titanium show maximum enhancement by 48% followed by Cr (20%) and Mn (36%). At the same time trace element concentration of Sr and Pb are declaimed by 30% and 20% in women population. Physical basis of used analytical methods, experimental set-up and the procedure of sample preparation are described

FIB-SEM imaging of carbon nanotubes in mouse lung tissue

DEFF Research Database (Denmark)

Købler, Carsten; Saber, Anne Thoustrup; Jacobsen, Nicklas Raun

2014-01-01

Ultrastructural characterisation is important for understanding carbon nanotube (CNT) toxicity and how the CNTs interact with cells and tissues. The standard method for this involves using transmission electron microscopy (TEM). However, in particular, the sample preparation, using a microtome...

Distribution of basic fibroblast growth factor binding sites in various tissue membrane preparations from adult guinea pig

International Nuclear Information System (INIS)

Ledoux, D.; Mereau, A.; Dauchel, M.C.; Barritault, D.; Courty, J.

1989-01-01

In order to localize a rich source of basic FGF receptor, we examined the distribution of basic FGF binding sites in brain, stomach, lung, spleen, kidney, liver and intestine membrane preparations from adult guinea pig. Comparative binding studies using iodinated basic FGF showed that a specific binding was detected in all the membrane preparations tested. Scatchard plots from iodinated basic FGF competition experiment with native basic FGF in various membrane preparations, suggested the presence of one class of binding sites in some tissues such as liver, kidney, spleen, lung, stomach, and intestine with an apparent dissociation constant (appKD) value ranging from 4 to 7.5 nM and the existence of a second class of higher affinity sites in brain membranes with appKD value of 15 pM. Characterization of these basic FGF high affinity interaction sites was performed using a cross-linking reagent. These results show for the first time that specific interaction sites for basic FGF are widely distributed, suggesting that this growth factor might play a role in the physiological functions of a number of adult organs

Field Sample Preparation Method Development for Isotope Ratio Mass Spectrometry

International Nuclear Information System (INIS)

Leibman, C.; Weisbrod, K.; Yoshida, T.

2015-01-01

Non-proliferation and International Security (NA-241) established a working group of researchers from Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Savannah River National Laboratory (SRNL) to evaluate the utilization of in-field mass spectrometry for safeguards applications. The survey of commercial off-the-shelf (COTS) mass spectrometers (MS) revealed no instrumentation existed capable of meeting all the potential safeguards requirements for performance, portability, and ease of use. Additionally, fieldable instruments are unlikely to meet the International Target Values (ITVs) for accuracy and precision for isotope ratio measurements achieved with laboratory methods. The major gaps identified for in-field actinide isotope ratio analysis were in the areas of: 1. sample preparation and/or sample introduction, 2. size reduction of mass analyzers and ionization sources, 3. system automation, and 4. decreased system cost. Development work in 2 through 4, numerated above continues, in the private and public sector. LANL is focusing on developing sample preparation/sample introduction methods for use with the different sample types anticipated for safeguard applications. Addressing sample handling and sample preparation methods for MS analysis will enable use of new MS instrumentation as it becomes commercially available. As one example, we have developed a rapid, sample preparation method for dissolution of uranium and plutonium oxides using ammonium bifluoride (ABF). ABF is a significantly safer and faster alternative to digestion with boiling combinations of highly concentrated mineral acids. Actinides digested with ABF yield fluorides, which can then be analyzed directly or chemically converted and separated using established column chromatography techniques as needed prior to isotope analysis. The reagent volumes and the sample processing steps associated with ABF sample digestion lend themselves to automation and field

Preparation and evaluation of reference materials for accountancy analysis. (1) Preparation and evaluation method

International Nuclear Information System (INIS)

Takamatsu, Mai; Kacchi, Tomokazu; Murakami, Toshiki; Ai, Hironobu; Sumi, Mika; Abe, Katsuo; Kageyama, Tomio; Nakazawa, Hiroaki

2009-01-01

Isotope dilution mass spectrometry method used for the accountancy analysis at nuclear fuel facilities requires the standard materials called LSD (Large Size Dried) spike. Generally, LSD spikes are prepared from certified reference materials (CRMs) which supplied from foreign laboratories. However, the difficulty of Pu CRM importation is increasing. It is important for safeguards to attain and continue high reliable accountancy analysis and stable securing of LSD spike is essential. Therefore, in order to conserve CRMs, several types of LSD spike were prepared under collaboration work between JAEA and JNFL, such as the amount of nuclear material in one LSD spike is decreased and others. Practical test with actual samples were performed at JNFL Rokkasho reprocessing plant, and those results were compared with the results obtained by using LSD spike which supplied from foreign laboratory. Preparation and verification analysis of LSD spikes and evaluation of uncertainty based on ISO-GUM will be presented. (author)

Method for increasing nuclear magnetic resonance signals in living biological tissue

International Nuclear Information System (INIS)

Krongrad, A.

1995-01-01

A method of enhancing a magnetic resonance comprising the steps of administering a quantity of a selected magnetic isotope to a living biological tissue at a concentration greater than the naturally occurring concentration of such isotope and detecting magnetic resonance signal from the administered magnetic isotope in the living biological tissue. (author)

An improved method of preparation of nanoparticular metal oxide catalysts

DEFF Research Database (Denmark)

2014-01-01

The present invention concerns an improved method of preparation of nanoparticular vanadium oxide/anatase titania catalysts having a narrow particle size distribution. In particular, the invention concerns preparation of nanoparticular vanadium oxide/anatase titania catalyst precursors comprising...... combustible crystallization seeds upon which the catalyst metal oxide is coprecipitated with the carrier metal oxide, which crystallization seeds are removed by combustion in a final calcining step....

BOWEL PREPARATION BEFORE COLONOSCOPY FOR CHILDREN: comparison of efficacy of three different methods

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Seyed Mohsen DEHGHANI

2015-12-01

Full Text Available Background - Colonoscopy is an important diagnostic and therapeutic procedure. Adequate bowel preparation is mandatory. Several regimens were discussed in the literature. Among the drugs which has recently used, polyethylene glycol is one of the most popular agents. Objectives - The aim of this study was to compare efficacy of three different methods for 1 day preparation before colonoscopy. Methods - This study included children with the range of ages (2-21 who had an indication of colonoscopy. Exclusion criteria were based on the history of previous surgery, parental disagreement, and patients who did not use preparation protocol. Three methods for bowel preparation were studied: 1- Polyethylene glycol only; 2- Polyethylene glycol and bisacodyl suppositories; 3- Polyethylene glycol plus normal saline enema. Boston Bowel Preparation Score was used for evaluation of preparation. SPSS version 16.0 (Chicago, IL, USA were used for data analysis. Results - In this study 83 cases completed the bowel preparation completely. Acceptable bowel preparation was seen in 24 (85.71%, 36 (94.73%, and 14 (82.35% of cases in PEG, PEG + bisacodyl, and PEG + normal saline enema groups respectively. PEG + bisacodyl suppositories was more effective than PEG + normal saline for the preparation of the first segment ( P=0.05. For second and third segment of colon, BPPS score was higher in PEG + bisacodyl suppositories compared to other regimens, but this difference was not statistically significant. Conclusion - There was no significant difference between 1 day colonoscopy regimens in terms of bowel preparation score. Lowest score was seen in PEG + enema group compared to other group.

Methods for quantifying adipose tissue insulin resistance in overweight/obese humans.

Science.gov (United States)

Ter Horst, K W; van Galen, K A; Gilijamse, P W; Hartstra, A V; de Groot, P F; van der Valk, F M; Ackermans, M T; Nieuwdorp, M; Romijn, J A; Serlie, M J

2017-08-01

Insulin resistance of adipose tissue is an important feature of obesity-related metabolic disease. However, assessment of lipolysis in humans requires labor-intensive and expensive methods, and there is limited validation of simplified measurement methods. We aimed to validate simplified methods for the quantification of adipose tissue insulin resistance against the assessment of insulin sensitivity of lipolysis suppression during hyperinsulinemic-euglycemic clamp studies. We assessed the insulin-mediated suppression of lipolysis by tracer-dilution of [1,1,2,3,3- 2 H 5 ]glycerol during hyperinsulinemic-euglycemic clamp studies in 125 overweight or obese adults (85 men, 40 women; age 50±11 years; body mass index 38±7 kg m -2 ). Seven indices of adipose tissue insulin resistance were validated against the reference measurement method. Low-dose insulin infusion resulted in suppression of the glycerol rate of appearance ranging from 4% (most resistant) to 85% (most sensitive), indicating a good range of adipose tissue insulin sensitivity in the study population. The reference method correlated with (1) insulin-mediated suppression of plasma glycerol concentrations (r=0.960, PInsulin Resistance (Adipo-IR) index (fasting plasma insulin-NEFA product; r=-0.526, Pinsulin-glycerol product (r=-0.467, PInsulin Resistance Index (fasting plasma insulin-basal lipolysis product; r=0.460, PInsulin Sensitivity Check Index (QUICKI)-NEFA index (r=0.621, Pinsulin resistance (area under the curve ⩾0.801, Pinsulin sensitivity (that is, the antilipolytic action of insulin) can be reliably quantified in overweight and obese humans by simplified index methods. The sensitivity and specificity of the Adipo-IR index and the fasting plasma insulin-glycerol product, combined with their simplicity and acceptable agreement, suggest that these may be most useful in clinical practice.

Comparison of Preparation Methods of Copper Based PGMFree Diesel-Soot Oxidation Catalysts

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R. Prasad

2011-05-01

Full Text Available CuO-CeO2 systems have been proposed as a promising catalyst for low temperature diesel-soot oxidation. CuO-CeO2 catalysts prepared by various methods were examined for air oxidation of the soot in a semi batch tubular flow reactor. The air oxidation of soot was carried out under tight contact with soot/catalyst ratio of 1/10. Air flow rate was 150 ml/min, soot-catalyst mixture was 110 mg, heating rate was 5 0C/min. Prepared catalysts were calcined at 500 0C and their stability was examined by further heating to 800 0C for 4 hours. It was found that the selectivity of all the catalysts was nearly 100% to CO2 production. It was observed that the activity and stability of the catalysts greatly influenced by the preparation methods. The strong interaction between CuO and CeO2 is closely related to the preparation route that plays a crucial role in the soot oxidation over the CuO-CeO2 catalysts. The ranking order of the preparation methods of the catalysts in the soot oxidation performance is as follows: sol-gel > urea nitrate combustion > Urea gelation method > thermal decomposition > co-precipitation. Copyright © 2011 BCREC UNDIP. All rights reserved.(Received: 27th June 2010, Revised: 7th August 2010; Accepted: 13rd October 2010[How to Cite: R. Prasad, V.R. Bella. (2011. Comparison of Preparation Methods of Copper Based PGMFree Diesel-Soot Oxidation Catalysts. Bulletin of Chemical Reaction Engineering and Catalysis, 6(1: 15-21. doi:10.9767/bcrec.6.1.822.15-21][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.822.15-21 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/822 | View in 

Optimization of preparation of skilled wrestlers by perfection of method of the special preparation

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Ogar' G.O.

2009-12-01

Full Text Available The author method of the special physical preparation of skilled fighters is presented. A method carries stage-by-stage character. On the first stage effectively to conduct the accented power training. On the second stage - to perfect explosive force. Tasks of the third stage are perfection of speed force and lactate component of energy supply. On the fourth stage the special is perfected speed-power endurance. The fifth stage coincides with beginning of competition period of macrocycle.

Development of sample preparation method for honey analysis using PIXE

International Nuclear Information System (INIS)

Saitoh, Katsumi; Chiba, Keiko; Sera, Koichiro

2008-01-01

We developed an original preparation method for honey samples (samples in paste-like state) specifically designed for PIXE analysis. The results of PIXE analysis of thin targets prepared by adding a standard containing nine elements to honey samples demonstrated that the preparation method bestowed sufficient accuracy on quantitative values. PIXE analysis of 13 kinds of honey was performed, and eight mineral components (Si, P, S, K, Ca, Mn, Cu and Zn) were detected in all honey samples. The principal mineral components were K and Ca, and the quantitative value for K accounted for the majority of the total value for mineral components. K content in honey varies greatly depending on the plant source. Chestnuts had the highest K content. In fact, it was 2-3 times that of Manuka, which is known as a high quality honey. K content of false-acacia, which is produced in the greatest abundance, was 1/20 that of chestnuts. (author)

High-throughput simultaneous analysis of RNA, protein, and lipid biomarkers in heterogeneous tissue samples.

Science.gov (United States)

Reiser, Vladimír; Smith, Ryan C; Xue, Jiyan; Kurtz, Marc M; Liu, Rong; Legrand, Cheryl; He, Xuanmin; Yu, Xiang; Wong, Peggy; Hinchcliffe, John S; Tanen, Michael R; Lazar, Gloria; Zieba, Renata; Ichetovkin, Marina; Chen, Zhu; O'Neill, Edward A; Tanaka, Wesley K; Marton, Matthew J; Liao, Jason; Morris, Mark; Hailman, Eric; Tokiwa, George Y; Plump, Andrew S

2011-11-01

With expanding biomarker discovery efforts and increasing costs of drug development, it is critical to maximize the value of mass-limited clinical samples. The main limitation of available methods is the inability to isolate and analyze, from a single sample, molecules requiring incompatible extraction methods. Thus, we developed a novel semiautomated method for tissue processing and tissue milling and division (TMAD). We used a SilverHawk atherectomy catheter to collect atherosclerotic plaques from patients requiring peripheral atherectomy. Tissue preservation by flash freezing was compared with immersion in RNAlater®, and tissue grinding by traditional mortar and pestle was compared with TMAD. Comparators were protein, RNA, and lipid yield and quality. Reproducibility of analyte yield from aliquots of the same tissue sample processed by TMAD was also measured. The quantity and quality of biomarkers extracted from tissue prepared by TMAD was at least as good as that extracted from tissue stored and prepared by traditional means. TMAD enabled parallel analysis of gene expression (quantitative reverse-transcription PCR, microarray), protein composition (ELISA), and lipid content (biochemical assay) from as little as 20 mg of tissue. The mean correlation was r = 0.97 in molecular composition (RNA, protein, or lipid) between aliquots of individual samples generated by TMAD. We also demonstrated that it is feasible to use TMAD in a large-scale clinical study setting. The TMAD methodology described here enables semiautomated, high-throughput sampling of small amounts of heterogeneous tissue specimens by multiple analytical techniques with generally improved quality of recovered biomolecules.

OBT analysis method using polyethylene beads for limited quantities of animal tissue

International Nuclear Information System (INIS)

Kim, S.B.; Stuart, M.

2015-01-01

This study presents a polyethylene beads method for OBT determination in animal tissues and animal products for cases where the amount of water recovered by combustion is limited by sample size or quantity. In the method, the amount of water recovered after combustion is enhanced by adding tritium-free polyethylene beads to the sample prior to combustion in an oxygen bomb. The method reduces process time by allowing the combustion water to be easily collected with a pipette. Sufficient water recovery was achieved using the polyethylene beads method when 2 g of dry animal tissue or animal product were combusted with 2 g of polyethylene beads. Correction factors, which account for the dilution due to the combustion water of the beads, are provided for beef, chicken, pork, fish and clams, as well as egg, milk and cheese. The method was tested by comparing its OBT results with those of the conventional method using animal samples collected on the Chalk River Laboratories (CRL) site. The results determined that the polyethylene beads method added no more than 25% uncertainty when appropriate correction factors are used. - Highlights: • Polyethylene beads method for OBT determination in animal tissues and animal products were determined. • The method reduces process time. • The polyethylene beads method added no more than 25% uncertainty when appropriate correction factors are used

Review of Research on Template Methods in Preparation of Nanomaterials

OpenAIRE

Yadian Xie; Duygu Kocaefe; Chunying Chen; Yasar Kocaefe

2016-01-01

The nanomaterials have been widely used in various fields, such as photonics, catalysis, and adsorption, because of their unique physical and chemical properties. Therefore, their production methods are of utmost importance. Compared with traditional synthetic methods, the template method can effectively control the morphology, particle size, and structure during the preparation of nanomaterials, which is an effective method for their synthesis. The key for the template method is to choose di...

The application of lesion sterilization and tissue repair 3Mix-MP for treating rat's dental pulp tissue

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Raditya Nugroho

2015-03-01

Full Text Available Background: Lesion sterilization and tissue repair (LSTR 3Mix-MP are three broad-spectrum antibiotics, including metronidazole, ciprofloxacin and minocycline are mixed with propylene glycol or macrogol. There is the possibility ofthe healing process that marked proliferation ofnew blood vessels and proliferation offibroblasts in the treatment ofirreversible pulpitis by pulp capping LSTR 3MixMP because of  the principle of the method LSTR 3Mix-MP is to kill bacteria. Purpose: The purpose of this study to prove the effect of LSTR 3Mix-MP on chronic inflammation and the healing process in rat dental pulp tissue in vivo. Methods: Rattus norvegicus anaesthetized by using ketamine and xylazine dissolved in sterile isotonic saline solution (0.2 ml/50gr mm on the upper right thigh. Cavity preparation class I to perforation by using a low speed tapered diamond round bur. In the treatment group, rats were treated 3Mix-MP at a dose of10 mg and then covered with glass ionomer cement for 7 days on the pulp that has been opened for 3 days. The control group treated with saline irrigation on the pulp that has been opened for 3 days. Rats were killed after seven days, and then made preparations pulp tissue to count the number oflymphocytes, macrophages, plasma cells, blood vessels, and fibroblasts Results: There is an increase in the average number ofmacrophage cells, plasma, and fibroblasts; and decreased lymphocytes and blood vessels in the treated group exposure LSTR 3Mix-MP. Conclusion:LSTR 3Mix-MP can reduce chronic inflammation process and enhance the healing process in rat dental pulp tissue.

Optical clearing of tissues and blood using the immersion method

International Nuclear Information System (INIS)

Tuchin, Valery V

2005-01-01

This paper aims to review recent results on the optical clearing of the naturally turbid biological tissues and blood using the optical immersion technique, which is well known in physical science and is applied for the reduction of light scattering and undesirable reflections in the optical system. Basic principles of the technique, its advantages, limitations and future are discussed. The refractive index matching concept for enhancement of in-depth light penetration into tissues and blood is presented on the basis of in vitro and in vivo studies using optical spectroscopy, polarization and coherence-domain techniques. The index matching of scatterers and ground matter by means of administration of clearing agents is under discussion. The optical properties of tissues with basic multiple scattering, which are transformed to a low scattering mode, are analysed. It is shown that light reflection, transmission, scattering and polarization can be effectively controlled. The possibilities of using the optical immersion method for diagnostic purposes based on contrasting of abnormalities, on in-depth profiling of tissue and blood and on monitoring of endogenous and exogenous matter diffusion within tissue are demonstrated

Preparation and application of an innovative thrombocyte/leukocyte-enriched plasma to promote tissue repair in chelonians.

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Francesco Di Ianni

Full Text Available Platelet concentrates are widely used in mammalian regenerative medicine to improve tissue healing. Chelonians (Testudines would benefit from the application of thrombocyte preparations to regenerate damaged tissues, since traumatic injuries are leading causes of morbidity and mortality for both wild-living and domesticated animals. The aim of this study was to establish a protocol that optimized the recovery of the thrombocytes from blood samples and to show the efficacy of thrombocyte-enriched plasma in chelonians. Peripheral blood samples were obtained from Testudo spp. (n = 12 and Trachemys scripta elegans (n = 10. Blood cells were fractionated by sodium diatrizoate-sodium polysucrose density gradient using a two-step centrifugation protocol. Thrombocytes and leukocytes were isolated and resuspended to obtain thrombocyte-leucocyte rich plasma (TLRP. The mean recovery of leukocytes and thrombocytes was 48.9% (±4.0 SEM, n = 22 of the whole blood cell content. No statistically significant difference was observed between blood samples collected from different turtle species. The ability of TLRP to form a gel was evaluated by adding variable concentrations of calcium gluconate at room temperature and at 37°C. A reliable and consistent clotting of the TLRP was obtained in glass tubes and dishes by adding 5-20% v/v of a 100 mg/ml solution of calcium gluconate. Furthermore, in order to test the clinical efficacy of TLRP, a preliminary evaluation was performed on four turtles (Testudo spp. with traumatic injuries. In all the four animals, a successful clinical outcome was observed. The results demonstrated that a thrombocyte-enriched plasma, comparable to mammalian platelet rich plasma, can be prepared from chelonian blood samples. Furthermore, although the low number of cases presented does not allow definitive conclusions from a clinical point of view, their outcome suggests that TLRP application could be further investigated to improve the

Preparation and Application of an Innovative Thrombocyte/Leukocyte-Enriched Plasma to Promote Tissue Repair in Chelonians

Science.gov (United States)

Di Ianni, Francesco; Merli, Elisa; Burtini, Francesca; Conti, Virna; Pelizzone, Igor; Di Lecce, Rosanna; Parmigiani, Enrico; Squassino, Gian Paolo; Del Bue, Maurizio; Lucarelli, Enrico; Ramoni, Roberto; Grolli, Stefano

2015-01-01

Platelet concentrates are widely used in mammalian regenerative medicine to improve tissue healing. Chelonians (Testudines) would benefit from the application of thrombocyte preparations to regenerate damaged tissues, since traumatic injuries are leading causes of morbidity and mortality for both wild-living and domesticated animals. The aim of this study was to establish a protocol that optimized the recovery of the thrombocytes from blood samples and to show the efficacy of thrombocyte-enriched plasma in chelonians. Peripheral blood samples were obtained from Testudo spp. (n = 12) and Trachemys scripta elegans (n = 10). Blood cells were fractionated by sodium diatrizoate-sodium polysucrose density gradient using a two-step centrifugation protocol. Thrombocytes and leukocytes were isolated and resuspended to obtain thrombocyte-leucocyte rich plasma (TLRP). The mean recovery of leukocytes and thrombocytes was 48.9% (±4.0 SEM, n = 22) of the whole blood cell content. No statistically significant difference was observed between blood samples collected from different turtle species. The ability of TLRP to form a gel was evaluated by adding variable concentrations of calcium gluconate at room temperature and at 37°C. A reliable and consistent clotting of the TLRP was obtained in glass tubes and dishes by adding 5-20% v/v of a 100 mg/ml solution of calcium gluconate. Furthermore, in order to test the clinical efficacy of TLRP, a preliminary evaluation was performed on four turtles (Testudo spp.) with traumatic injuries. In all the four animals, a successful clinical outcome was observed. The results demonstrated that a thrombocyte-enriched plasma, comparable to mammalian platelet rich plasma, can be prepared from chelonian blood samples. Furthermore, although the low number of cases presented does not allow definitive conclusions from a clinical point of view, their outcome suggests that TLRP application could be further investigated to improve the healing process of

A comparison of the microstructures and electrochemical capacitive properties of 2 graphenes prepared by arc discharge method and chemical method

Energy Technology Data Exchange (ETDEWEB)

Zhang, H.; Yang, Y. [Research Inst. of Chemical Defense, Beijing (China); Univ. of Science and Technology, Beijing (China); Cao, G.; Xu, B. [Research Inst. of Chemical Defense, Beijing (China)

2010-07-01

In this study, 2 kinds of graphene materials were prepared using both arc discharge and chemical methods. The pore structures and electrochemical capacitive properties of the materials were investigated. A mesopore structure was obtained for the graphene prepared using the arc discharge method, with a capacitance of 12.9 F/g and a high rate capability when used in electrochemical applications. The graphene prepared with the chemical method demonstrated a more highly developed micropore structure and capacitances greater than 70 F/g. However, rate performance for the graphene was normal. 2 figs.

Preparation of colloidal gold for staining proteins electrotransferred onto nitrocellulose membranes.

Science.gov (United States)

Yamaguchi, K; Asakawa, H

1988-07-01

This paper describes a simple method of preparing colloidal gold for staining protein blots. Colloidal gold was prepared from 0.005 or 0.01% HAuCl4 by the addition of formalin as a reductant and potassium hydroxide. Staining of small cell carcinoma tissue extract blotted onto nitrocellulose membranes with this colloidal gold solution resulted in the appearance of a large number of clear wine-red bands. The sensitivity of gold staining was 60 times higher than that of Coomassie brilliant blue staining and almost comparable to that of silver staining of proteins in polyacrylamide gel. The sensitivity of this method was also satisfactory in comparison with that of enzyme immunoblotting. The colloidal gold prepared by this method is usable for routine work.

Evaluation of small intestine grafts decellularization methods for corneal tissue engineering.

Directory of Open Access Journals (Sweden)

Ana Celeste Oliveira

Full Text Available Advances in the development of cornea substitutes by tissue engineering techniques have focused on the use of decellularized tissue scaffolds. In this work, we evaluated different chemical and physical decellularization methods on small intestine tissues to determine the most appropriate decellularization protocols for corneal applications. Our results revealed that the most efficient decellularization agents were the SDS and triton X-100 detergents, which were able to efficiently remove most cell nuclei and residual DNA. Histological and histochemical analyses revealed that collagen fibers were preserved upon decellularization with triton X-100, NaCl and sonication, whereas reticular fibers were properly preserved by decellularization with UV exposure. Extracellular matrix glycoproteins were preserved after decellularization with SDS, triton X-100 and sonication, whereas proteoglycans were not affected by any of the decellularization protocols. Tissue transparency was significantly higher than control non-decellularized tissues for all protocols, although the best light transmittance results were found in tissues decellularized with SDS and triton X-100. In conclusion, our results suggest that decellularized intestinal grafts could be used as biological scaffolds for cornea tissue engineering. Decellularization with triton X-100 was able to efficiently remove all cells from the tissues while preserving tissue structure and most fibrillar and non-fibrillar extracellular matrix components, suggesting that this specific decellularization agent could be safely used for efficient decellularization of SI tissues for cornea TE applications.

Immunological methods for the detection and determination of connective tissue proteoglycans

DEFF Research Database (Denmark)

Caterson, B; Baker, J R; Christner, J E

1982-01-01

In this paper we report the use of immunological methods for specifically detecting and determining proteoglycan in cartilage and other connective tissues. Antibodies (polyclonal and monoclonal) have been raised against specific components of cartilage proteoglycan aggregates (i.e., proteoglycan...... surrounding invaginating hair follicles. These immunological procedures are currently being used to complement conventional biochemical analyses of proteoglycans found in different connective tissue matrices....

Collagen immobilized PVA hydrogel-hydroxyapatite composites prepared by kneading methods as a material for peripheral cuff of artificial cornea

International Nuclear Information System (INIS)

Kobayashi, Hisatoshi; Kato, Masabumi; Taguchi, Tetsushi; Ikoma, Toshiyuki; Miyashita, Hideyuki; Shimmura, Shigeto; Tsubota, Kazuo; Tanaka, Junzo

2004-01-01

In order to achieve the firm fixation of the artificial cornea to host tissues, composites of collagen-immobilized poly(vinyl alcohol) hydrogel with hydroxyapatite were synthesized by a hydroxyapatite particles kneading method. The preparation method, characterization, and the results of corneal cell adhesion and proliferation on the composite material were studied. PVA-COL-HAp composites were successfully synthesized. A micro-porous structure of the PVA-COL-HAp could be introduced by hydrochloric acid treatment and the porosity could be controlled by the pH of the hydrochloric acid solution, the treatment time, and the crystallinity of the HAp particles. Chick embryonic keratocyto-like cells were well attached and proliferated on the PVA-COL-HAp composites. This material showed potential for keratoprosthesis application. Further study such as a long-term animal study is now required

Application of Micro-coprecipitation Method to Alpha Source Preparation for Measuring Alpha Nuclides

International Nuclear Information System (INIS)

Lee, Myung Ho; Park, Jong Ho; Oh, Se Jin; Song, Byung Chul; Song, Kyuseok

2011-01-01

Among the source preparations, an electrodeposition is a commonly used method for the preparation of sources for an alpha spectrometry, because this technique is simple and produces a very thin deposit, which is essential for a high resolution of the alpha peak. Recently, micro-coprecipitation with rare earths have been used to yield sources for -spectrometry. In this work, the Pu, Am and Cm isotopes were purified from hindrance nuclides and elements with an a TRU resin in radioactive waste samples, and the activity concentrations of the Pu, Am and Cm isotopes were determined by radiation counting methods after alpha source preparation like micro coprecipitation. After the Pu isotopes in the radioactive waste samples were separated from the other nuclides with an anion exchange resin, the Am isotopes were purified with a TRU resin and an anion exchange resin or a TRU resin. Activity concentrations and chemical recoveries of 241 Am purified with the TRU resin were similar to those with the TRU resin and anion exchange resin. In this study, to save on the analytical time and cost, the Am isotopes were purified with the TRU resin without using an additional anion exchange resin. After comparing the electrodeposition method with the micro-coprecipitation method, the micro-coprecipitation method was used for the alpha source preparation, because the micro-coprecipitation method is simple and more reliable for source preparation of the Pu, Am and Cm isotopes

A facile synthesis method of hydroxyethyl cellulose-silver nanoparticle scaffolds for skin tissue engineering applications.

Science.gov (United States)

Zulkifli, Farah Hanani; Hussain, Fathima Shahitha Jahir; Zeyohannes, Senait Sileshi; Rasad, Mohammad Syaiful Bahari Abdull; Yusuff, Mashitah M

2017-10-01

Green porous and ecofriendly scaffolds have been considered as one of the potent candidates for tissue engineering substitutes. The objective of this study is to investigate the biocompatibility of hydroxyethyl cellulose (HEC)/silver nanoparticles (AgNPs), prepared by the green synthesis method as a potential host material for skin tissue applications. The substrates which contained varied concentrations of AgNO 3 (0.4%-1.6%) were formed in the presence of HEC, were dissolved in a single step in water. The presence of AgNPs was confirmed visually by the change of color from colorless to dark brown, and was fabricated via freeze-drying technique. The outcomes exhibited significant porosity of >80%, moderate degradation rate, and tremendous value of water absorption up to 1163% in all samples. These scaffolds of HEC/AgNPs were further characterized by SEM, UV-Vis, ATR-FTIR, TGA, and DSC. All scaffolds possessed open interconnected pore size in the range of 50-150μm. The characteristic peaks of Ag in the UV-Vis spectra (417-421nm) revealed the formation of AgNPs in the blend composite. ATR-FTIR curve showed new existing peak, which implies the oxidation of HEC in the cellulose derivatives. The DSC thermogram showed augmentation in T g with increased AgNO 3 concentration. Preliminary studies of cytotoxicity were carried out in vitro by implementation of the hFB cells on the scaffolds. The results substantiated low toxicity of HEC/AgNPs scaffolds, thus exhibiting an ideal characteristic in skin tissue engineering applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Automatic method for selective enhancement of different tissue densities at digital chest radiography

International Nuclear Information System (INIS)

McNitt-Gray, M.F.; Taira, R.K.; Eldredge, S.L.; Razavi, M.

1991-01-01

This paper reports that digital chest radiographs often are too bright and/or lack contrast when viewed on a video display. The authors have developed a method that can automatically provide a series of look-up tables that selectively enhance the radiographically soft or dense tissues on a digital chest radiograph. This reduces viewer interaction and improves displayed image quality. On the basis of a histogram analysis, gray-level ranges are approximated for the patient background, radiographically soft tissues, and radiographically dense tissues. A series of look-up tables is automatically created by varying the contrast in each range to achieve a level of enhancement for a selected tissue range. This is repeated for differing amounts of enhancement and for each tissue range. This allows the viewer to interactively select a tissue density range and degree of enhancement at the time of display via precalculated look-up tables. Preclinical trials in pediatric radiology using computed radiography images show that this method reduces viewer interaction and improves or maintains the displayed image quality

Method of tissue repair using a composite material

Energy Technology Data Exchange (ETDEWEB)

Hutchens, Stacy A.; Woodward, Jonathan; Evans, Barbara R.; O' Neill, Hugh M.

2016-03-01

A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

Method of tissue repair using a composite material

Science.gov (United States)

Hutchens, Stacy A; Woodward, Jonathan; Evans, Barbara R; O'Neill, Hugh M

2014-03-18

A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

Skeletal muscle tissue engineering: methods to form skeletal myotubes and their applications.

Science.gov (United States)

Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu; Khademhosseini, Ali

2014-10-01

Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined.

Development of method of tritium labeling of pharmacological preparate of drotaverine hydrochloride (NOSPA)

International Nuclear Information System (INIS)

Kim, A.A.; Djuraeva, G.T.; Shukurov, B.V.

2004-01-01

Full text: The method for tritium labeling of pharmacological preparate of drotaverine hydrochloride (no spa) was developed. Drotaverine hydrochloride was labeled by thermally activated tritium in apparatus for tritium labeling. The optimum regime of labeling was selected. The system of purification of tritium labeled drotaverine hydrochloride by thin layer chromatography (TLC) has been developed. The TLC system of purification of tritium labeled drotaverine hydrochloride was developed. Tritium labeled preparation of drotaverine hydrochloride was purified by TLC on silicagel in system isopropanol: ammonia: water (8:1:1). We found appearance of additional fractions in tritium labeled preparation of drotaverine hydrochloride that testifies to partial transformation of drotaverine hydrochloride during procedure of labeling. Application of TLC for purification of tritium labeled preparation allows to purify completely drotaverine hydrochloride of by-products. The output of purified tritium labeled preparation of drotaverine hydrochloride was about 25 %. The received preparation had specific radioactivity - 3,2 MBq/mg, radiochemical purity of a preparation was 95 %. TLC purification seems inexpensive, fast and suitable for purification of tritium-labeled drotaverine hydrochloride. Thus developed method allows obtain tritium labeled preparation of drotaverine hydrochloride (no - spa), suitable for medical and biologic researches

Preparing Methods and Its Influencing Factors about Nanoparticles Based on Dendritic Polymer

OpenAIRE

Zhang Jianwei; Li Jeff

2017-01-01

Based on the properties, structure and application of dendritic polymer, this paper analysed the methods of the preparation of nanoparticles using dendritic polymer, detailed preparation process, technical parameters and application effect about a single metal nanoparticles, bimetallic nanoparticles, sulfide and halide nanoparticles. The influencing factors of the preparation about nanoparticles were discussed, including the molecular algebra, the molar ratio of the metal ions to the dendriti...

Evaluation of a Method for Quantifying Eugenol Concentrations in the Fillet Tissue from Freshwater Fish Species.

Science.gov (United States)

Meinertz, Jeffery R; Schreier, Theresa M; Porcher, Scott T; Smerud, Justin R

2016-01-01

AQUI-S 20E(®) (active ingredient, eugenol; AQUI-S New Zealand Ltd, Lower Hutt, New Zealand) is being pursued for approval as an immediate-release sedative in the United States. A validated method to quantify the primary residue (the marker residue) in fillet tissue from AQUI-S 20E-exposed fish was needed. A method was evaluated for determining concentrations of the AQUI-S 20E marker residue, eugenol, in freshwater fish fillet tissue. Method accuracies from fillet tissue fortified at nominal concentrations of 0.15, 1, and 60 μg/g from six fish species ranged from 88-102%. Within-day and between-day method precisions (% CV) from the fortified tissue were ≤8.4% CV. There were no coextracted compounds from the control fillet tissue of seven fish species that interfered with eugenol analyses. Six compounds used as aquaculture drugs did not interfere with eugenol analyses. The lower limit of quantitation (LLOQ) was 0.012 μg/g. The method was robust, i.e., in most cases, minor changes to the method did not impact method performance. Eugenol was stable in acetonitrile-water (3 + 7, v/v) for at least 14 days, in fillet tissue extracts for 4 days, and in fillet tissue stored at ~ -80°C for at least 84 days.

Magnetite–hematite nanoparticles prepared by green methods for heavy metal ions removal from water

International Nuclear Information System (INIS)

Ahmed, M.A.; Ali, S.M.; El-Dek, S.I.; Galal, A.

2013-01-01

Graphical abstract: The negatively charged cubic magnetite nanoparticles, prepared by the coprecipitation method in N 2 atmosphere, can adsorb up to 99% of the positively charged toxic heavy metal ions at a proper pH value. -- Highlights: • Mixed magnetite–hematite nanoparticles were synthesized via different routes. • Prepared samples were characterized by XRD, HRTEM, BET and magnetic hysteresis. • The material was employed as a sorbent for removal of some heavy metal ions from water. • The effects of pH and the contact time on the adsorption process were studied and optimized. -- Abstract: Mixed magnetite–hematite nanoparticles were synthesized via different routes such as, coprecipitation in air and N 2 atmosphere, citrate–nitrate, glycine–nitrate and microwave-assisted citrate methods. The prepared samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM), BET measurements and magnetic hysteresis. XRD data showed the formation of magnetite–hematite mixture with different compositions according to the synthesis method. The particle size was in the range of 4–52 nm for all the prepared samples. From HRTEM micrographs, it was found that, the synthesis method affects the moropholgy of the prepared samples in terms of crystallinity and porosity. The magnetite–hematite mixture was employed as a sorbent material for removal of some heavy metal ions from water such as lead(II), cadmium(II) and chromium(III). The effects of pH value and the contact time on the adsorption process were studied and optimized in order to obtain the highest possible adsorption efficiency of the magnetite–hematite mixture. The effect of the synthesis method of the magnetite–hematite mixture on the adsorption process was also investigated. It was found that samples prepared by the coprecipitation method had better adsorption efficiency than those prepared by other combustion methods

Thermal stability of octadecylsilane hybrid silicas prepared by grafting and sol-gel methods

International Nuclear Information System (INIS)

Brambilla, Rodrigo; Santos, Joao H.Z. dos; Miranda, Marcia S.L.; Frost, Ray L.

2008-01-01

Hybrid silicas bearing octadecylsilane groups were prepared by grafting and sol-gel (SG) methods. The effect of the preparative route on the thermal stability was evaluated by means of thermal gravimetric analysis (TGA), infrared emission spectroscopy (IRES) and, complementary, by 13 C solid-state nuclear magnetic resonance ( 13 C NMR) and matrix assisted laser deionization time of flight mass spectroscopy (MALDI-TOF-MS). Silicas prepared by the grafting route seem to be slightly more stable than those produced by the sol-gel method. This behavior seems to be associated to the preparative route, since grafting affords a liquid-like conformation, while in the case of sol-gel a highly organized crystalline chain conformation was observed

Method of preparing radionuclide doses

International Nuclear Information System (INIS)

Kuperus, J.H.

1987-01-01

A method is described of preparing aliquot dosea of a tracer material useful in diagnostic nuclear medicine comprising: storing discrete quantities of a lyophilized radionuclide carrier in separate tubular containers from which air and moisture is excluded, selecting from the tubular containers a container in which is stored a carrier appropriate for a nuclear diagnostic test to be performed, interposing the selected container between the needle and the barrel of a hypodermic syringe, and drawing a predetermined amount of a liquid containing a radionuclide tracer in known concentration into the hypodermic syringe barrel through the hypodermic needle and through the selected container to dissolve the discrete quantity of lyophilized carrier therein to combine the carrier with the radionuclide tracer to form an aliquot dose of nuclear diagnostic tracer material, as needed

Automated MALDI Matrix Coating System for Multiple Tissue Samples for Imaging Mass Spectrometry

Science.gov (United States)

Mounfield, William P.; Garrett, Timothy J.

2012-03-01

Uniform matrix deposition on tissue samples for matrix-assisted laser desorption/ionization (MALDI) is key for reproducible analyte ion signals. Current methods often result in nonhomogenous matrix deposition, and take time and effort to produce acceptable ion signals. Here we describe a fully-automated method for matrix deposition using an enclosed spray chamber and spray nozzle for matrix solution delivery. A commercial air-atomizing spray nozzle was modified and combined with solenoid controlled valves and a Programmable Logic Controller (PLC) to control and deliver the matrix solution. A spray chamber was employed to contain the nozzle, sample, and atomized matrix solution stream, and to prevent any interference from outside conditions as well as allow complete control of the sample environment. A gravity cup was filled with MALDI matrix solutions, including DHB in chloroform/methanol (50:50) at concentrations up to 60 mg/mL. Various samples (including rat brain tissue sections) were prepared using two deposition methods (spray chamber, inkjet). A linear ion trap equipped with an intermediate-pressure MALDI source was used for analyses. Optical microscopic examination showed a uniform coating of matrix crystals across the sample. Overall, the mass spectral images gathered from tissues coated using the spray chamber system were of better quality and more reproducible than from tissue specimens prepared by the inkjet deposition method.

Preparation of SnO2 Nanoparticles by Two Different Wet Chemistry Methods

International Nuclear Information System (INIS)

Ridha, N.J.; Akrajas Ali Umar; Muhammad Yahya; Muhammad Mat Salleh; Mohamad Hafizuddin Jumali

2011-01-01

The objective of this project is to prepare SnO 2 nanoparticles by two different wet chemistry methods namely sol gel and direct growth methods. The XRD results indicated that both samples are single phase SnO 2 . The FE-SEM micrographs displayed that SnO 2 nanoparticles prepared in first method exhibited a round shape with particle size around 15 nm while the second method produced SnO 2 nano rod with length and width of 570 nm and 55 nm respectively. Energy gap values for SnO 2 nanospheres and nano rods were 4.38 and 4.34 eV respectively. (author)

Should the mass of a nanoferrite sample prepared by autocombustion method be considered as a realistic preparation parameter?

Energy Technology Data Exchange (ETDEWEB)

Wahba, Adel Maher, E-mail: adel.mousa@f-eng.tanta.edu.eg [Department of Engineering Physics and Mathematics, Faculty of Engineering, Tanta University (Egypt); Mohamed, Mohamed Bakr [Ain shams University, Faculty of Science, Physics Department, Cairo (Egypt)

2017-02-15

Detectable variations in structural, elastic and magnetic properties have been reported depending on the mass of the cobalt nanoferrite sample prepared by citrate autocombustion method. Heat released during the autocombustion process and its duration are directly proportional to the mass to be prepared, and is thus expected to affect both the crystallite size and the cation distribution giving rise to the reported variations in microstrain, magnetization, and coercivity. Formation of a pure spinel phase has been validated using X-ray diffraction patterns (XRD) and Fourier-transform infrared (FTIR) spectra. Crystallite sizes obtained from Williamson-Hall (W-H) method range from 28–87 nm, being further supported by images of high-resolution transmission electron microscope (HRTEM). Saturation magnetization and coercivity deduced from M-H hysteresis loops show a clear correlation with the cation distribution, which was proposed on the basis of experimentally obtained data of XRD, VSM, and IR. Elastic parameters have been estimated using the cation distribution and FTIR data, with a resulting trend quite opposite to that of the lattice parameter. - Highlights: • Samples with different masses of CoFe{sub 2}O{sub 4} were prepared by autocombustion method. • XRD and IR data confirmed a pure spinel cubic structure for all samples. • Structural and magnetic properties show detectable changes with the mass prepared. • Cation distribution was suggested from experimental data of XRD, IR, and M-H loops.

A Review of Photocatalysts Prepared by Sol-Gel Method for VOCs Removal

Directory of Open Access Journals (Sweden)

Ting Ke Tseng

2010-05-01

Full Text Available The sol-gel process is a wet-chemical technique (chemical solution deposition, which has been widely used in the fields of materials science, ceramic engineering, and especially in the preparation of photocatalysts. Volatile organic compounds (VOCs are prevalent components of indoor air pollution. Among the approaches to remove VOCs from indoor air, photocatalytic oxidation (PCO is regarded as a promising method. This paper is a review of the status of research on the sol-gel method for photocatalyst preparation and for the PCO purification of VOCs. The review and discussion will focus on the preparation and coating of various photocatalysts, operational parameters, and will provide an overview of general PCO models described in the literature.

Method of preparing composite superconducting wire

International Nuclear Information System (INIS)

Verhoeven, J. D.; Finnemore, D. K.; Gibson, E. D.; Ostenson, J. E.; Schmidt, F. A.

1985-01-01

An improved method of preparing composite multifilament superconducting wire of Nb 3 Sn in a copper matrix which eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb 3 Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting

The Influence of Tissue Lyophilization and Gamma Irradiation on the Solubility of Proteins

International Nuclear Information System (INIS)

Komender, J.; Jendyk, J.; Leibschang, J.

1967-01-01

Most recent methods of tissue preservation are based on lyophilization and sterilization with gamma rays. Unfortunately the tissues preserved by this method lose their viability, this being connected with protein denaturation. The denaturing influence either of lyophilization or sterilization with gamma rays on different materials has been described. However, no observations on denaturation of proteins in prepared grafts are known. The work aimed at establishing the influence of individual stages of the procedure used in a tissue bank on the solubility of proteins. An experiment was performed using rat liver as a model tissue. Solubility of protein was determined in five groups of material, as follows: (1) fresh tissue, used as a control, (2) frozen tissue, (3) frozen and lyophilized tissue, (4) frozen, lyophilized and irradiated tissue, and (5) fresh irradiated tissue. Folin's method was used for determination of protein in water extracts of tissues. It was found that: (1) the whole procedure considerably diminished the protein solubility, (2) freezing diminishes the protein solubility by 35% on average, (3) lyophilization causes no further protein denaturation, (4) protein solubility is reduced most (by about 65%) by sterilization with gamma rays. (author)

PATMA: parser of archival tissue microarray

Directory of Open Access Journals (Sweden)

Lukasz Roszkowiak

2016-12-01

Full Text Available Tissue microarrays are commonly used in modern pathology for cancer tissue evaluation, as it is a very potent technique. Tissue microarray slides are often scanned to perform computer-aided histopathological analysis of the tissue cores. For processing the image, splitting the whole virtual slide into images of individual cores is required. The only way to distinguish cores corresponding to specimens in the tissue microarray is through their arrangement. Unfortunately, distinguishing the correct order of cores is not a trivial task as they are not labelled directly on the slide. The main aim of this study was to create a procedure capable of automatically finding and extracting cores from archival images of the tissue microarrays. This software supports the work of scientists who want to perform further image processing on single cores. The proposed method is an efficient and fast procedure, working in fully automatic or semi-automatic mode. A total of 89% of punches were correctly extracted with automatic selection. With an addition of manual correction, it is possible to fully prepare the whole slide image for extraction in 2 min per tissue microarray. The proposed technique requires minimum skill and time to parse big array of cores from tissue microarray whole slide image into individual core images.

Improved perovskite phototransistor prepared using multi-step annealing method

Science.gov (United States)

Cao, Mingxuan; Zhang, Yating; Yu, Yu; Yao, Jianquan

2018-02-01

Organic-inorganic hybrid perovskites with good intrinsic physical properties have received substantial interest for solar cell and optoelectronic applications. However, perovskite film always suffers from a low carrier mobility due to its structural imperfection including sharp grain boundaries and pinholes, restricting their device performance and application potential. Here we demonstrate a straightforward strategy based on multi-step annealing process to improve the performance of perovskite photodetector. Annealing temperature and duration greatly affects the surface morphology and optoelectrical properties of perovskites which determines the device property of phototransistor. The perovskite films treated with multi-step annealing method tend to form highly uniform, well-crystallized and high surface coverage perovskite film, which exhibit stronger ultraviolet-visible absorption and photoluminescence spectrum compare to the perovskites prepared by conventional one-step annealing process. The field-effect mobilities of perovskite photodetector treated by one-step direct annealing method shows mobility as 0.121 (0.062) cm2V-1s-1 for holes (electrons), which increases to 1.01 (0.54) cm2V-1s-1 for that treated with muti-step slow annealing method. Moreover, the perovskite phototransistors exhibit a fast photoresponse speed of 78 μs. In general, this work focuses on the influence of annealing methods on perovskite phototransistor, instead of obtains best parameters of it. These findings prove that Multi-step annealing methods is feasible to prepared high performance based photodetector.

Methods for the preparation of protein-oligonucleotide-lipid constructs.

Science.gov (United States)

Takasaki, Jennifer; Raney, Sameersingh G; Chikh, Ghania; Sekirov, Laura; Brodsky, Irina; Tam, Ying; Ansell, Steven M

2006-01-01

A mixture of ionizable cationic lipids, steric barrier lipids, and colipids is used to encapsulate oligonucleotide DNA in lipidic particles called SALP. This material is under development as an adjuvant for vaccines. Previously we have shown that coupling the antigen directly to the surface of SALP can lead to enhanced immunological responses in vivo. Two different methods for preparing ovalbumin-SALP were assessed in this work. Originally the conjugates were prepared by treating SALP containing a maleimide-derivatized lipid with thiolated ovalbumin, a method we refer to as active coupling. This reaction was found to be difficult to control and generally resulted in low coupling efficiencies. The issues relating to this approach were characterized. We have recently developed alternative techniques based on first coupling ovalbumin to a micelle and then incubating the resultant product with SALP, methods we refer to as passive coupling. We have shown that this method allows accurate control of the levels of protein associated SALP and does not suffer from surface saturation effects seen with the active coupling method that places maximum limits on the amount of protein that can be coupled to the SALP surface. The products from the passive coupling protocol are shown to have activity comparable to those derived from the active coupling protocol in investigations of in vivo immune responses.

Method of preparing tritium-labelled thymidine-5'-monophosphates of high specific activity

International Nuclear Information System (INIS)

Filip, J.; Vesely, J.; Cihak, A.

1976-01-01

A method is described of preparing thymidine-5'-monophosphates labelled with tritium of high specific activity based on enzyme synthesis in vitro. Phosphorylation was carried out using the catalytic effect of an enzyme contained in the supernatant fraction prepared from Yoshida ascites carcinoma in rats. The course of the enzyme reaction can be controlled by the concentration of the individual reaction mixture components. The method described allows obtaining thymidine-5'-monophosphate of radiochemical purity better than 95%. (J.B.)

Evaluation of Pentachlorophenol Residues in Some Hygienic Papers Prepared from Virgin and Secondary Pulp by Electron Capture Gas Chromatographic Method

Directory of Open Access Journals (Sweden)

Behrouz Akbari-adergani

2016-01-01

Full Text Available In this study, residual amount of pentachlorophenol (PCP as the most important paper preservative, which is extremely hazardous pollutant, was determined in some tissue papers and napkins. Twenty-five samples of two producing hygienic paper factories prepared from virgin and secondary pulp were analyzed for the presence of trace amount of PCP. The analytical procedure involved direct extraction of PCP from hygienic paper and its determination by gas chromatography with electron capture detection. The statistical results for the analysis of all samples revealed that there were significant differences between mean of PCP in hygienic papers prepared from virgin and secondary pulp (P<0.05. This method gave recoveries of 86-98% for hygienic paper made from virgin pulp and 79-92% for hygienic paper made from secondary pulp. The limit of detection (LOD and limit of quantification (LOQ for PCP were 6.3 and 21.0 mg/kg, respectively. The analytical method has the requisite sensitivity, accuracy, precision and specificity to assay PCP in hygienic papers. This study demonstrates a concern with exposition to PCP considering that hygienic paper is largely consumed in the society.

Photocatalytic degradation of textile dyestuffs using TiO{sub 2} nanotubes prepared by sonoelectrochemical method

Energy Technology Data Exchange (ETDEWEB)

Tekin, Derya, E-mail: deryatekin@atauni.edu.tr

2014-11-01

Highlights: • TiO{sub 2} nanotubes prepared by electrochemical and sonoelectrochemical method. • More regular TiO{sub 2} nanotubes diameters prepared by sonoelectrochemical method. • Obtained nanotubes were used in the photocatalytic degradation of Orange G dye. • TiO{sub 2} nanotubes prepared by sonoelectrochemical method showed 10% faster degradation of Orange G dye compared with the one by electrochemical method. - Abstract: TiO{sub 2} nanotubes were prepared by anodization of Ti plates by conventional electrochemical technique as well as by an emerging sonoelectrochemical technique. Scanning electron miscroscope (SEM) analysis showed that ultrasound assisted anodization yielded more ordered and controllable TiO{sub 2} tube banks with higher tube diameter. The photocatalytical activities of TiO{sub 2} nanotubes were tested in the photocatalytical degradation of Orange G dye. The results showed that sonoelectrochemically prepared TiO{sub 2} tubes exhibited 10% higher photocatalytic performance than the electrochemical prepared ones, and more than 18% higher activity than the other TiO{sub 2} samples.

A Stereological Method for the Quantitative Evaluation of Cartilage Repair Tissue

Science.gov (United States)

Nyengaard, Jens Randel; Lind, Martin; Spector, Myron

2015-01-01

Objective To implement stereological principles to develop an easy applicable algorithm for unbiased and quantitative evaluation of cartilage repair. Design Design-unbiased sampling was performed by systematically sectioning the defect perpendicular to the joint surface in parallel planes providing 7 to 10 hematoxylin–eosin stained histological sections. Counting windows were systematically selected and converted into image files (40-50 per defect). The quantification was performed by two-step point counting: (1) calculation of defect volume and (2) quantitative analysis of tissue composition. Step 2 was performed by assigning each point to one of the following categories based on validated and easy distinguishable morphological characteristics: (1) hyaline cartilage (rounded cells in lacunae in hyaline matrix), (2) fibrocartilage (rounded cells in lacunae in fibrous matrix), (3) fibrous tissue (elongated cells in fibrous tissue), (4) bone, (5) scaffold material, and (6) others. The ability to discriminate between the tissue types was determined using conventional or polarized light microscopy, and the interobserver variability was evaluated. Results We describe the application of the stereological method. In the example, we assessed the defect repair tissue volume to be 4.4 mm3 (CE = 0.01). The tissue fractions were subsequently evaluated. Polarized light illumination of the slides improved discrimination between hyaline cartilage and fibrocartilage and increased the interobserver agreement compared with conventional transmitted light. Conclusion We have applied a design-unbiased method for quantitative evaluation of cartilage repair, and we propose this algorithm as a natural supplement to existing descriptive semiquantitative scoring systems. We also propose that polarized light is effective for discrimination between hyaline cartilage and fibrocartilage. PMID:26069715

Enhanced dissolution of meloxicam from orodispersible tablets prepared by different methods

Directory of Open Access Journals (Sweden)

Ahmed Abd Elbary

2012-12-01

Full Text Available The objective of this study was formulation, development and evaluation of meloxicam orodispersible tablets. ODTs were prepared by two methods including sublimation technique where different subliming agents like camphor, menthol and thymol were used with Ac-Di-Sol as a superdisintegrant. Each subliming agent was used in three different concentrations (5, 10 and 15% w/w. Tablets were first prepared and later exposed to vacuum. Meloxicam ODTs were also prepared by freeze-drying an aqueous dispersion of meloxicam containing a matrix former, a sugar alcohol, and a collapse protectant. In addition, different disintegration accelerators were tested (each in 1% w/v including PVP K25, PVP K90, PEG 6000, PEG 4000, PEG 400, tween 80 and tween 20. The prepared ODTs from two methods were evaluated for weight variation, thickness, drug content, friability, hardness, wetting time, in vitro disintegration time and in vitro dissolution study. The best formulation was subjected to stability testing for 3 months at temperatures 40 °C and 75% relative humidity and at 60 °C. All formulations showed disintegration time ranging from 1 to 46 s. All the prepared formulae complied with the pharmacopoeial requirements of the drug contents. T17 gave the best in vitro disintegration and dissolution results. ODT formula T17 has shown no appreciable changes with respect to physical characters, meloxicam content and dissolution profiles when stored at elevated temperatures. In conclusion the results of this work suggest that orodispersible tablets of meloxicam with rapid disintegration time, fast drug release and good hardness can be efficiently and successfully formulated by employing freeze drying and sublimation methods.

[Biocybernetic approach to the thermometric methods of blood supply measurements of periodontal tissues].

Science.gov (United States)

Pastusiak, J; Zakrzewski, J

1988-11-01

Specific biocybernetic approach to the problem of the blood supply determination of paradontium tissues by means of thermometric methods has been presented in the paper. The compartment models of the measuring procedure have been given. Dilutodynamic methology and classification has been applied. Such an approach enables to select appropriate biophysical parameters describing the state of blood supply of paradontium tissues and optimal design of transducers and measuring methods.

Methods for designing building envelope components prepared for repair and maintenance

DEFF Research Database (Denmark)

Rudbeck, Claus Christian

2000-01-01

the deterministic and probabilistic approach. Based on an investigation of the data-requirement, user-friendliness and supposed accuracy (the accuracy of the different methods has not been evaluated due to the absence of field data) the method which combines the deterministic factor method with statistical...... to be prepared for repair and maintenance. Both of these components are insulation systems for flat roofs and low slope roofs; components where repair or replacement is very expensive if the roofing material fails in its function. The principle of both roofing insulation systems is that the insulation can...... of issues which are specified below:Further development of methods for designing building envelope components prepared for repair and maintenance, and ways of tracking and predicting performance through time once the components have been designed, implemented in a building design and built...

Nuclear analytical methods for trace element studies in calcified tissues

International Nuclear Information System (INIS)

Chaudhry, M.A.; Chaudhry, M.N.

2001-01-01

Full text: Various nuclear analytical methods have been developed and applied to determine the elemental composition of calcified tissues (teeth and bones). Fluorine was determined by prompt gamma activation analysis through the 19 F(p,ag) 16 O reaction. Carbon was measured by activation analysis with He-3 ions, and the technique of Proton-Induced X-ray Emission (PIXE) was applied to simultaneously determine Ca, P, and trace elements in well-documented teeth. Dental hard tissues, enamel, dentine, cement, and their junctions, as well as different parts of the same tissue, were examined separately. Furthermore, using a Proton Microprobe, we measured the surface distribution of F and other elements on and around carious lesions on the enamel. The depth profiles of F, and other elements, were also measured right up to the amelodentin junction

Alternate method of source preparation for alpha spectrometry: No electrodeposition, no hydrofluoric acid

International Nuclear Information System (INIS)

Kurosaki, Hiromu; Mueller, Rebecca J.; Lambert, Susan B.; Rao, Govind R.

2016-01-01

An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride micro-precipitation. The method uses lanthanide hydroxide micro-precipitation to avoid the use of hazardous hydrofluoric acid. Lastly, it provides a quicker, simpler, and safer way of preparing actinide alpha counting sources in routine, production-type laboratories that process many samples daily.

Alternate method of source preparation for alpha spectrometry: no electrodeposition, no hydrofluoric acid

International Nuclear Information System (INIS)

Hiromu Kurosaki; Lambert, S.B.; Rao, G.R.; Mueller, R.J.

2017-01-01

An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride micro-precipitation. The method uses lanthanide hydroxide micro-precipitation to avoid the use of hazardous hydrofluoric acid. It provides a quicker, simpler, and safer way of preparing actinide alpha counting sources in routine, production-type laboratories that process many samples daily. (author)

Automated quantification of renal interstitial fibrosis for computer-aided diagnosis: A comprehensive tissue structure segmentation method.

Science.gov (United States)

Tey, Wei Keat; Kuang, Ye Chow; Ooi, Melanie Po-Leen; Khoo, Joon Joon

2018-03-01

Interstitial fibrosis in renal biopsy samples is a scarring tissue structure that may be visually quantified by pathologists as an indicator to the presence and extent of chronic kidney disease. The standard method of quantification by visual evaluation presents reproducibility issues in the diagnoses. This study proposes an automated quantification system for measuring the amount of interstitial fibrosis in renal biopsy images as a consistent basis of comparison among pathologists. The system extracts and segments the renal tissue structures based on colour information and structural assumptions of the tissue structures. The regions in the biopsy representing the interstitial fibrosis are deduced through the elimination of non-interstitial fibrosis structures from the biopsy area and quantified as a percentage of the total area of the biopsy sample. A ground truth image dataset has been manually prepared by consulting an experienced pathologist for the validation of the segmentation algorithms. The results from experiments involving experienced pathologists have demonstrated a good correlation in quantification result between the automated system and the pathologists' visual evaluation. Experiments investigating the variability in pathologists also proved the automated quantification error rate to be on par with the average intra-observer variability in pathologists' quantification. Interstitial fibrosis in renal biopsy samples is a scarring tissue structure that may be visually quantified by pathologists as an indicator to the presence and extent of chronic kidney disease. The standard method of quantification by visual evaluation presents reproducibility issues in the diagnoses due to the uncertainties in human judgement. An automated quantification system for accurately measuring the amount of interstitial fibrosis in renal biopsy images is presented as a consistent basis of comparison among pathologists. The system identifies the renal tissue structures

In-air micro-pixe analysis of tissue samples

International Nuclear Information System (INIS)

Tanaka, A.; Ishii, K.; Komori, Y.

2002-01-01

Micro-PIXE is capable of providing spatial distributions of elements in the micro-meter scale and its application to biology is useful to elucidate the cellular metabolism. Since, in this method, a sample target is usually irradiated with proton or α-particle beams in vacuum, beam heating results in evaporation of volatile elements an shrinking of the sample. In order to avoid these side effects, we previously developed a technique of in-air micro-PIXE analysis for samples of cultured cells. In addition to these, analysis of exposed tissue samples from living subjects is highly desirable in biological and medical research. Here, we describe a technique of in-air micro-PIXE analysis of such tissue samples. The target samples of exposed tissue slices from a Donryu rat, in which a tumor had been transplanted, were analyzed with proton micro-beams of 2.6 MeV. We report that the shape of cells and the distribution of volatile elements in the tissue sample remain uncharged when using a target preparation based on a freeze-drying method. (author)

The autologus graft of epithelial tissue culture

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Minaee B

1999-08-01

Full Text Available With the intention of research about culture and autologus graft of epithelial tissue we used 4 french Albino Rabbits with an average age of 2 months. After reproduction on the support in EMEM (Eagle's Minimum Essential Medium we used this for graft after 4 weeks. This region which grafted total replaced. After fixation of this sample and passing them through various process, histological sections were prepared. These sections were stained with H & E and masson's trichrome and studied by light microscope. We succeeded in graft. We hope in the near future by using the method of epithelium tissue culture improving to treat burned patients.

Influence of Thermal Preparation Method on Mineral Composition of Mussels

Directory of Open Access Journals (Sweden)

Gheorghe Valentin GORAN

2018-02-01

Full Text Available This study focuses on evaluation of the effects of 3 different thermal preparation methods (boiling, roasting, microwaving on mineral concentrations of mussels from Bucharest market. The mineral content in raw and cooked mussel samples was evaluated by ICP-OES and relative humidity of raw and cooked mussels by thermogravimetry. Se level in microwaved samples was significantly decreased compared to raw and the other 2 cooked mussel samples. Zn concentration in raw samples was not significantly different compared to those in roasted samples. Fe level was insignificantly different between boiled and roasted samples and significantly lowers in microwaved samples. Ni, Pb, and Se levels were significantly higher in boiled samples, and Cd levels were insignificantly different reported to cooking method. The percentage of water loss during roasting was lower than the other 2 thermal preparation methods. Potassium concentrations in cooked mussels were higher compared to raw ones. Mineral concentrations were highest in roasted samples and heavy metal concentrations in boiled mussels.

Gravimetric method for the determination of diclofenac in pharmaceutical preparations.

Science.gov (United States)

Tubino, Matthieu; De Souza, Rafael L

2005-01-01

A gravimetric method for the determination of diclofenac in pharmaceutical preparations was developed. Diclofenac is precipitated from aqueous solution with copper(II) acetate in pH 5.3 (acetic acid/acetate buffer). Sample aliquots had approximately the same quantity of the drug content in tablets (50 mg) or in ampules (75 mg). The observed standard deviation was about +/- 2 mg; therefore, the relative standard deviation (RSD) was approximately 4% for tablet and 3% for ampule preparations. The results were compared with those obtained with the liquid chromatography method recommended in the United States Pharmacopoeia using the statistical Student's t-test. Complete agreement was observed. It is possible to obtain more precise results using higher aliquots, for example 200 mg, in which case the RSD falls to 1%. This gravimetric method, contrary to what is expected for this kind of procedure, is relatively fast and simple to perform. The main advantage is the absolute character of the gravimetric analysis.

Preparation and biological properties of a novel composite scaffold of nano-hydroxyapatite/chitosan/carboxymethyl cellulose for bone tissue engineering

Directory of Open Access Journals (Sweden)

Chengdong Xiong

2009-07-01

Full Text Available Abstract In this study, we report the physico-chemical and biological properties of a novel biodegradable composite scaffold made of nano-hydroxyapatite and natural derived polymers of chitosan and carboxymethyl cellulose, namely, n-HA/CS/CMC, which was prepared by freeze-drying method. The physico-chemical properties of n-HA/CS/CMC scaffold were tested by infrared absorption spectra (IR, transmission electron microscope(TEM, scanning electron microscope(SEM, universal material testing machine and phosphate buffer solution (PBS soaking experiment. Besides, the biological properties were evaluated by MG63 cells and Mesenchymal stem cells (MSCs culture experiment in vitro and a short period implantation study in vivo. The results show that the composite scaffold is mainly formed through the ionic crossing-linking of the two polyions between CS and CMC, and n-HA is incorporated into the polyelectrolyte matrix of CS-CMC without agglomeration, which endows the scaffold with good physico-chemical properties such as highly interconnected porous structure, high compressive strength and good structural stability and degradation. More important, the results of cells attached, proliferated on the scaffold indicate that the scaffold is non-toxic and has good cell biocompatibility, and the results of implantation experiment in vivo further confirm that the scaffold has good tissue biocompatibility. All the above results suggest that the novel degradable n-HA/CS/CMC composite scaffold has a great potential to be used as bone tissue engineering material.

Preparation and biological properties of a novel composite scaffold of nano-hydroxyapatite/chitosan/carboxymethyl cellulose for bone tissue engineering

Science.gov (United States)

Liuyun, Jiang; Yubao, Li; Chengdong, Xiong

2009-01-01

In this study, we report the physico-chemical and biological properties of a novel biodegradable composite scaffold made of nano-hydroxyapatite and natural derived polymers of chitosan and carboxymethyl cellulose, namely, n-HA/CS/CMC, which was prepared by freeze-drying method. The physico-chemical properties of n-HA/CS/CMC scaffold were tested by infrared absorption spectra (IR), transmission electron microscope(TEM), scanning electron microscope(SEM), universal material testing machine and phosphate buffer solution (PBS) soaking experiment. Besides, the biological properties were evaluated by MG63 cells and Mesenchymal stem cells (MSCs) culture experiment in vitro and a short period implantation study in vivo. The results show that the composite scaffold is mainly formed through the ionic crossing-linking of the two polyions between CS and CMC, and n-HA is incorporated into the polyelectrolyte matrix of CS-CMC without agglomeration, which endows the scaffold with good physico-chemical properties such as highly interconnected porous structure, high compressive strength and good structural stability and degradation. More important, the results of cells attached, proliferated on the scaffold indicate that the scaffold is non-toxic and has good cell biocompatibility, and the results of implantation experiment in vivo further confirm that the scaffold has good tissue biocompatibility. All the above results suggest that the novel degradable n-HA/CS/CMC composite scaffold has a great potential to be used as bone tissue engineering material. PMID:19594953

Effect of surfactants on the properties of hydrotalcites prepared by the reverse micelle method

Energy Technology Data Exchange (ETDEWEB)

Holgado, Patricia H., E-mail: h.holgado@usal.es; Holgado, María J., E-mail: holgado@usal.es; San Román, María S., E-mail: sanroman@usal.es; Rives, Vicente, E-mail: vrives@usal.es

2015-02-01

Layered double hydroxides with the hydrotalcite-type structure have been prepared by the reverse micelles method. The layer cations were Ni{sup 2+} and Fe{sup 3+} in all cases and the interlayer anion was carbonate. We have studied the effect of the surfactant used (with linear chains of different lengths, or cyclic) and the effect of the pH on the properties of the solids formed. These have been characterized by element chemical analysis, powder X-ray diffraction, thermogravimetric analysis, temperature-programmed reduction, FT-IR and Vis–UV spectroscopies and scanning electron microscopy. It has been found that the samples prepared at pH 9 are more crystalline than those prepared at pH 11 and their crystallite sizes are always larger than for samples prepared by the conventional precipitation method. Surfactants with cyclic organic chains lead to a larger crystallite size, probably because the water pool vesicle where the crystallite grows is larger due to sterical hindrance of the organic chains. - Graphical abstract: Layered double hydroxides with the hydrotalcite-type structure with Ni{sup 2+} and Fe{sup 3+} cations in the layers have been prepared by the reverse micelles method. Different surfactants were used at different pH synthesis. Samples prepared at pH 9 are higher crystalline than those prepared at pH 11. Surfactants with cyclic organic chains lead to a larger crystallite size. - Highlights: • Hydrotalcites were prepared by the micelles reverse method. • Straight alkyl or cyclic chain surfactants were used. • All hydrotalcites are well crystallized at pH = 9 and 11. • The crystallite size depends on the linear/cyclic nature of the surfactant chain.

Effect of surfactants on the properties of hydrotalcites prepared by the reverse micelle method

International Nuclear Information System (INIS)

Holgado, Patricia H.; Holgado, María J.; San Román, María S.; Rives, Vicente

2015-01-01

Layered double hydroxides with the hydrotalcite-type structure have been prepared by the reverse micelles method. The layer cations were Ni 2+ and Fe 3+ in all cases and the interlayer anion was carbonate. We have studied the effect of the surfactant used (with linear chains of different lengths, or cyclic) and the effect of the pH on the properties of the solids formed. These have been characterized by element chemical analysis, powder X-ray diffraction, thermogravimetric analysis, temperature-programmed reduction, FT-IR and Vis–UV spectroscopies and scanning electron microscopy. It has been found that the samples prepared at pH 9 are more crystalline than those prepared at pH 11 and their crystallite sizes are always larger than for samples prepared by the conventional precipitation method. Surfactants with cyclic organic chains lead to a larger crystallite size, probably because the water pool vesicle where the crystallite grows is larger due to sterical hindrance of the organic chains. - Graphical abstract: Layered double hydroxides with the hydrotalcite-type structure with Ni 2+ and Fe 3+ cations in the layers have been prepared by the reverse micelles method. Different surfactants were used at different pH synthesis. Samples prepared at pH 9 are higher crystalline than those prepared at pH 11. Surfactants with cyclic organic chains lead to a larger crystallite size. - Highlights: • Hydrotalcites were prepared by the micelles reverse method. • Straight alkyl or cyclic chain surfactants were used. • All hydrotalcites are well crystallized at pH = 9 and 11. • The crystallite size depends on the linear/cyclic nature of the surfactant chain

The effects of crosslinkers on physical, mechanical, and cytotoxic properties of gelatin sponge prepared via in-situ gas foaming method as a tissue engineering scaffold.

Science.gov (United States)

Poursamar, S Ali; Lehner, Alexander N; Azami, Mahmoud; Ebrahimi-Barough, Somayeh; Samadikuchaksaraei, Ali; Antunes, A P M

2016-06-01

In this study porous gelatin scaffolds were prepared using in-situ gas foaming, and four crosslinking agents were used to determine a biocompatible and effective crosslinker that is suitable for such a method. Crosslinkers used in this study included: hexamethylene diisocyanate (HMDI), poly(ethylene glycol) diglycidyl ether (epoxy), glutaraldehyde (GTA), and genipin. The prepared porous structures were analyzed using Fourier Transform Infrared Spectroscopy (FT-IR), thermal and mechanical analysis as well as water absorption analysis. The microstructures of the prepared samples were analyzed using Scanning Electron Microscopy (SEM). The effects of the crosslinking agents were studied on the cytotoxicity of the porous structure indirectly using MTT analysis. The affinity of L929 mouse fibroblast cells for attachment on the scaffold surfaces was investigated by direct cell seeding and DAPI-staining technique. It was shown that while all of the studied crosslinking agents were capable of stabilizing prepared gelatin scaffolds, there are noticeable differences among physical and mechanical properties of samples based on the crosslinker type. Epoxy-crosslinked scaffolds showed a higher capacity for water absorption and more uniform microstructures than the rest of crosslinked samples, whereas genipin and GTA-crosslinked scaffolds demonstrated higher mechanical strength. Cytotoxicity analysis showed the superior biocompatibility of the naturally occurring genipin in comparison with other synthetic crosslinking agents, in particular relative to GTA-crosslinked samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Surface characterization of retinal tissues for the enhancement of vitreoretinal surgical methods

Science.gov (United States)

Valentin-Rodriguez, Celimar

Diabetic retinopathy is the most common ophthalmic complication of diabetes and the leading cause of blindness among adults, ages 30 to 70. Surgery to remove scar tissue in the eye is the only corrective treatment once the retina is affected. Visual recovery is often hampered by retinal trauma during surgery and by low patient compliance. Our work in this project aimed to improve vitreoretinal surgical methods from information gathered by sensitive surface analysis of pre-retinal tissues found at the vitreoretinal interface. Atomic force microscopy characterization of human retinal tissues revealed that surgically excised inner limiting membrane (ILM) has a heterogeneous surface and is mainly composed of globular and fibrous structures. ILM tissues also show low adhesion for clean unmodified surfaces as opposed to those with functional groups attractive to those on the ILM surface, due to their charge. Based on these observations, layer-by-layer films with embedded gold nanoparticles with a positive outer charge were designed. These modifications increased the adhesion between surgical instruments and ILM by increasing the roughness and tuning the film surface charge. These films proved to be stable under physiological conditions. Finally, the effect of vital dyes on the topographical characteristics of ILMs was characterized and new imaging modes to further reveal ILM topography were utilized. Roughness and adhesion force data suggest that second generation dyes have no effect on the surface nanostructure of ILMs, but increase adhesion at the tip sample interface. This project clearly illustrates that physicochemical information from tissues can be used to rationally re-design surgical procedures, in this case for tissue removal purposes. This rational design method can be applied to other soft tissue excision procedures as is the case of cataract surgery or laparoscopic removal of endometrial tissue.

Technetium-99m labeled radiodiagnostic agents and method of preparation

International Nuclear Information System (INIS)

Molinski, V.J.; Wilczewski, J.A.

1977-01-01

A method of preparing improved technetium-99m labeled radiodiagnostic agents by reducing technetium-99m with stannous tartrate is described. Such radiodiagnostic agents are useful in scintigraphic examinations of the bone and lung

Preparation of Zeolite Molecular Sieve by Using Hydrogel Method

International Nuclear Information System (INIS)

Swe Zin Win; Mu Mu Htay; Mya Mya Oo

2010-12-01

Zeolite A was synthesized from hydrogel solution which prepared from silica and alumina precursors under hydrothermal condition at atmospheric pressure. Before preparing of hydrogel solution, the amount of raw materials which used in resulting hydrogel with appropriate mole ratio was calculated by material balance. In this study,totally ten experiments were carried out for zeolite A formation. The important parameters for these experiments were the kinds of precursors,their concentration (starting material composition), synthesis time and temperature. All product samples from these experiments were characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and analyzed by gravimetric method. The results show that the favourable sample for this research work which can be prepared with a molar composition of SiO2: Al2O3: 2Na2O: 70H2O by agitation at room temperature for 30 minutes, ageing at room temperature and crystallization at 95Ccentre dot centre dot for 24hrs. The percent yield of favourable result is 70%.

Sonochemical preparation of magnetite nanoparticles by reverse precipitation method

OpenAIRE

Shuto, Tatsuya; Nakagoe, Osamu; Tanabe, Shuji

2008-01-01

Magnetic iron oxide nanoparticles were successfully prepared by reverse precipitation method with the assistance of ultrasound. Obtained nanoparticles were identified as magnetite (Fe_3O_4) by XRD measurement. It was found that obtained magnetite nanoparticles have small sizes (about 10.7 ±2.9 nm in diameter) and spherical shape by TEM observations. In reverse precipitation method, the dropping conditions of aqueous FeSO_4 solution affect on the sizes and uniformity of the products.

Evaluation of five DNA extraction methods for purification of DNA from atherosclerotic tissue and estimation of prevalence of Chlamydia pneumoniae in tissue from a Danish population undergoing vascular repair

Directory of Open Access Journals (Sweden)

Lindholt Jes S

2003-09-01

Full Text Available Abstract Background To date PCR detection of Chlamydia pneumoniae DNA in atherosclerotic lesions from Danish patients has been unsuccessful. To establish whether non-detection was caused by a suboptimal DNA extraction method, we tested five different DNA extraction methods for purification of DNA from atherosclerotic tissue. Results The five different DNA extraction methods were tested on homogenate of atherosclerotic tissue spiked with C. pneumoniae DNA or EB, on pure C. pneumoniae DNA samples and on whole C. pneumoniae EB. Recovery of DNA was measured with a C. pneumoniae-specific quantitative real-time PCR. A DNA extraction method based on DNA-binding to spin columns with a silica-gel membrane (DNeasy Tissue kit showed the highest recovery rate for the tissue samples and pure DNA samples. However, an automated extraction method based on magnetic glass particles (MagNA Pure performed best on intact EB and atherosclerotic tissue spiked with EB. The DNeasy Tissue kit and MagNA Pure methods and the highly sensitive real-time PCR were subsequently used on 78 atherosclerotic tissue samples from Danish patients undergoing vascular repair. None of the samples were positive for C. pneumoniae DNA. The atherosclerotic samples were tested for inhibition by spiking with two different, known amounts of C. pneumoniae DNA and no samples showed inhibition. Conclusion As a highly sensitive PCR method and an optimised DNA extraction method were used, non-detection in atherosclerotic tissue from the Danish population was probably not caused by use of inappropriate methods. However, more samples may need to be analysed per patient to be completely certain on this. Possible methodological and epidemiological reasons for non-detection of C. pneumoniae DNA in atherosclerotic tissue from the Danish population are discussed. Further testing of DNA extraction methods is needed as this study has shown considerable intra- and inter-method variation in DNA recovery.

BOWEL PREPARATION BEFORE COLONOSCOPY FOR CHILDREN: comparison of efficacy of three different methods.

Science.gov (United States)

Dehghani, Seyed Mohsen; Javaherizadeh, Hazhir; Haghighat, Mahmood; Imanieh, Mohammad-Hadi; Ghanbari, Saeed

2015-12-01

Colonoscopy is an important diagnostic and therapeutic procedure. Adequate bowel preparation is mandatory. Several regimens were discussed in the literature. Among the drugs which has recently used, polyethylene glycol is one of the most popular agents. The aim of this study was to compare efficacy of three different methods for 1 day preparation before colonoscopy. This study included children with the range of ages (2-21) who had an indication of colonoscopy. Exclusion criteria were based on the history of previous surgery, parental disagreement, and patients who did not use preparation protocol. Three methods for bowel preparation were studied: 1- Polyethylene glycol only; 2- Polyethylene glycol and bisacodyl suppositories; 3- Polyethylene glycol plus normal saline enema. Boston Bowel Preparation Score was used for evaluation of preparation. SPSS version 16.0 (Chicago, IL, USA) were used for data analysis. In this study 83 cases completed the bowel preparation completely. Acceptable bowel preparation was seen in 24 (85.71%), 36 (94.73%), and 14 (82.35%) of cases in PEG, PEG + bisacodyl, and PEG + normal saline enema groups respectively. PEG + bisacodyl suppositories was more effective than PEG + normal saline for the preparation of the first segment ( P=0.05). For second and third segment of colon, BPPS score was higher in PEG + bisacodyl suppositories compared to other regimens, but this difference was not statistically significant. There was no significant difference between 1 day colonoscopy regimens in terms of bowel preparation score. Lowest score was seen in PEG + enema group compared to other group.

Preparation of nanocrystalline MgO by surfactant assisted precipitation method

International Nuclear Information System (INIS)

Rezaei, Mehran; Khajenoori, Majid; Nematollahi, Behzad

2011-01-01

Highlights: → Nanocrystalline magnesium oxide with high surface area. → MgO prepared with surfactant showed different morphologies compared with the sample prepared without surfactant. → MgO prepared with surfactant showed a plate-like shape. → Refluxing temperature and time and the surfactant to metal molar ratio affect the textural properties of MgO. -- Abstract: Nanocrystalline magnesium oxide with high surface area was prepared by a simple precipitation method using pluronic P123 triblock copolymer (Poly (ethylene glycol)-block, Poly (propylene glycol)-block, Poly (ethylene glycol)) as surfactant and under refluxing conditions. The prepared samples were characterized by X-ray diffraction (XRD), N 2 adsorption (BET) and scanning and transmission electron microscopies (SEM and TEM). The obtained results revealed that the refluxing time and temperature and the molar ratio of surfactant to metal affect the structural properties of MgO, because of the changes in the rate and extent of P123 adsorption on the prepared samples. The results showed that the addition of surfactant is effective to prepare magnesium oxide with high surface area and affects the morphology of the prepared samples. With increasing the P123/MgO molar ratio to 0.05 the pore size distribution was shifted to larger size. The sample prepared with addition of surfactant showed a plate-like shape which was completely different with the morphology of the sample prepared without surfactant. The formation of nanoplate-like MgO was related to higher surface density of Mg ions on the (0 0 1) plane than that on the other planes of the Mg(OH) 2 crystal. The (0 0 1) plane would be blocked preferentially by the adsorbed P123 molecules during the growing process of Mg(OH) 2 nanoentities and the growth on the (0 0 1) plane would be markedly restricted, and the consequence is the generation of nanoplate-like MgO. In addition, increase in refluxing temperature and time increased the specific surface area

Preparation of nanocrystalline MgO by surfactant assisted precipitation method

Energy Technology Data Exchange (ETDEWEB)

Rezaei, Mehran, E-mail: rezaei@kashanu.ac.ir [Catalyst and Advanced Materials Research Laboratory, Chemical Engineering Department, Faculty of Engineering, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Khajenoori, Majid; Nematollahi, Behzad [Catalyst and Advanced Materials Research Laboratory, Chemical Engineering Department, Faculty of Engineering, University of Kashan, Kashan (Iran, Islamic Republic of)

2011-10-15

Highlights: {yields} Nanocrystalline magnesium oxide with high surface area. {yields} MgO prepared with surfactant showed different morphologies compared with the sample prepared without surfactant. {yields} MgO prepared with surfactant showed a plate-like shape. {yields} Refluxing temperature and time and the surfactant to metal molar ratio affect the textural properties of MgO. -- Abstract: Nanocrystalline magnesium oxide with high surface area was prepared by a simple precipitation method using pluronic P123 triblock copolymer (Poly (ethylene glycol)-block, Poly (propylene glycol)-block, Poly (ethylene glycol)) as surfactant and under refluxing conditions. The prepared samples were characterized by X-ray diffraction (XRD), N{sub 2} adsorption (BET) and scanning and transmission electron microscopies (SEM and TEM). The obtained results revealed that the refluxing time and temperature and the molar ratio of surfactant to metal affect the structural properties of MgO, because of the changes in the rate and extent of P123 adsorption on the prepared samples. The results showed that the addition of surfactant is effective to prepare magnesium oxide with high surface area and affects the morphology of the prepared samples. With increasing the P123/MgO molar ratio to 0.05 the pore size distribution was shifted to larger size. The sample prepared with addition of surfactant showed a plate-like shape which was completely different with the morphology of the sample prepared without surfactant. The formation of nanoplate-like MgO was related to higher surface density of Mg ions on the (0 0 1) plane than that on the other planes of the Mg(OH){sub 2} crystal. The (0 0 1) plane would be blocked preferentially by the adsorbed P123 molecules during the growing process of Mg(OH){sub 2} nanoentities and the growth on the (0 0 1) plane would be markedly restricted, and the consequence is the generation of nanoplate-like MgO. In addition, increase in refluxing temperature and time

European Organisation for Research and Treatment of Cancer (EORTC) Pathobiology Group standard operating procedure for the preparation of human tumour tissue extracts suited for the quantitative analysis of tissue-associated biomarkers.

Science.gov (United States)

Schmitt, Manfred; Mengele, Karin; Schueren, Elisabeth; Sweep, Fred C G J; Foekens, John A; Brünner, Nils; Laabs, Juliane; Malik, Abha; Harbeck, Nadia

2007-03-01

With the new concept of 'individualized treatment and targeted therapies', tumour tissue-associated biomarkers have been given a new role in selection of cancer patients for treatment and in cancer patient management. Tumour biomarkers can give support to cancer patient stratification and risk assessment, treatment response identification, or to identifying those patients who are expected to respond to certain anticancer drugs. As the field of tumour-associated biomarkers has expanded rapidly over the last years, it has become increasingly apparent that a strong need exists to establish guidelines on how to easily disintegrate the tumour tissue for assessment of the presence of tumour tissue-associated biomarkers. Several mechanical tissue (cell) disruption techniques exist, ranging from bead mill homogenisation and freeze-fracturing through to blade or pestle-type homogenisation, to grinding and ultrasonics. Still, only a few directives have been given on how fresh-frozen tumour tissues should be processed for the extraction and determination of tumour biomarkers. The PathoBiology Group of the European Organisation for Research and Treatment of Cancer therefore has devised a standard operating procedure for the standardised preparation of human tumour tissue extracts which is designed for the quantitative analysis of tumour tissue-associated biomarkers. The easy to follow technical steps involved require 50-300 mg of deep-frozen cancer tissue placed into small size (1.2 ml) cryogenic tubes. These are placed into the shaking flask of a Mikro-Dismembrator S machine (bead mill) to pulverise the tumour tissue in the capped tubes in the deep-frozen state by use of a stainless steel ball, all within 30 s of exposure. RNA is isolated from the pulverised tissue following standard procedures. Proteins are extracted from the still frozen pulverised tissue by addition of Tris-buffered saline to obtain the cytosol fraction of the tumour or by the Tris buffer supplemented with

Calculating regional tissue volume for hyperthermic isolated limb perfusion: Four methods compared.

Science.gov (United States)

Cecchin, D; Negri, A; Frigo, A C; Bui, F; Zucchetta, P; Bodanza, V; Gregianin, M; Campana, L G; Rossi, C R; Rastrelli, M

2016-12-01

Hyperthermic isolated limb perfusion (HILP) can be performed as an alternative to amputation for soft tissue sarcomas and melanomas of the extremities. Melphalan and tumor necrosis factor-alpha are used at a dosage that depends on the volume of the limb. Regional tissue volume is traditionally measured for the purposes of HILP using water displacement volumetry (WDV). Although this technique is considered the gold standard, it is time-consuming and complicated to implement, especially in obese and elderly patients. The aim of the present study was to compare the different methods described in the literature for calculating regional tissue volume in the HILP setting, and to validate an open source software. We reviewed the charts of 22 patients (11 males and 11 females) who had non-disseminated melanoma with in-transit metastases or sarcoma of the lower limb. We calculated the volume of the limb using four different methods: WDV, tape measurements and segmentation of computed tomography images using Osirix and Oncentra Masterplan softwares. The overall comparison provided a concordance correlation coefficient (CCC) of 0.92 for the calculations of whole limb volume. In particular, when Osirix was compared with Oncentra (validated for volume measures and used in radiotherapy), the concordance was near-perfect for the calculation of the whole limb volume (CCC = 0.99). With methods based on CT the user can choose a reliable plane for segmentation purposes. CT-based methods also provides the opportunity to separate the whole limb volume into defined tissue volumes (cortical bone, fat and water). Copyright © 2016 Elsevier Ltd. All rights reserved.

The Resin-Embedded Cornea Prepared Via Rapid Processing Protocol : A Good Histomorphometric Target for Clinical Investigation in Ophthalmology and Optometry

Science.gov (United States)

Cheah, Pike See; Mohidin, Norhani; Mohd Ali, Bariah; Maung, Myint; Latif, Azian Abdul

2008-01-01

This study illustrates and quantifies the changes on corneal tissue between the paraffin-embedded and resin-embedded blocks and thus, selects a better target in investigational ophthalmology and optometry via light microscopy. Corneas of two cynomolgus monkeys (Macaca fascicularis) were used in this study. The formalin-fixed cornea was prepared in paraffin block via the conventional tissue processing protocol (4-day protocol) and stained with haematoxylin and eosin. The glutaraldehyde-fixed cornea was prepared in resin block via the rapid and modified tissue processing procedure (1.2-day protocol) and stained with toluidine blue. The paraffin-embedded sample exhibits various undesired tissue damage and artifact such as thinner epithelium (due to the substantial volumic extraction from the tissue), thicker stroma layer (due to the separation of lamellae and the presence of voids) and the distorted endothelium. In contrast, the resin-embedded corneal tissue has demonstrated satisfactory corneal ultrastructural preservation. The rapid and modified tissue processing method for preparing the resin-embedded is particularly beneficial to accelerate the microscopic evaluation in ophthalmology and optometry. PMID:22570589

Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue

Science.gov (United States)

Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.

1989-01-01

The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

THERMAL STABILITY OF Al-Cu-Fe QUASICRYSTALS PREPARED BY SHS METHOD

OpenAIRE

Pavel Novák; Alena Michalcová; Milena Voděrová; Ivo Marek; Dalibor Vojtěch

2013-01-01

Quasicrystal-containing materials are usually prepared by rapid solidification of the melt (e.g. by melt spinning) or mechanical alloying. In this work, the method using exothermic reactions between compressed metallic powders called SHS (Self-propagating High-temperature Synthesis) was tested. The microstructure and phase composition of the product was described in dependence on cooling regime from the reaction temperature. Thermal stability of prepared Al-Cu-Fe quasicrystals was studied by...

Molecular imaging of cannabis leaf tissue with MeV-SIMS method

Science.gov (United States)

Jenčič, Boštjan; Jeromel, Luka; Ogrinc Potočnik, Nina; Vogel-Mikuš, Katarina; Kovačec, Eva; Regvar, Marjana; Siketić, Zdravko; Vavpetič, Primož; Rupnik, Zdravko; Bučar, Klemen; Kelemen, Mitja; Kovač, Janez; Pelicon, Primož

2016-03-01

To broaden our analytical capabilities with molecular imaging in addition to the existing elemental imaging with micro-PIXE, a linear Time-Of-Flight mass spectrometer for MeV Secondary Ion Mass Spectrometry (MeV-SIMS) was constructed and added to the existing nuclear microprobe at the Jožef Stefan Institute. We measured absolute molecular yields and damage cross-section of reference materials, without significant alteration of the fragile biological samples during the duration of measurements in the mapping mode. We explored the analytical capability of the MeV-SIMS technique for chemical mapping of the plant tissue of medicinal cannabis leaves. A series of hand-cut plant tissue slices were prepared by standard shock-freezing and freeze-drying protocol and deposited on the Si wafer. We show the measured MeV-SIMS spectra showing a series of peaks in the mass area of cannabinoids, as well as their corresponding maps. The indicated molecular distributions at masses of 345.5 u and 359.4 u may be attributed to the protonated THCA and THCA-C4 acids, and show enhancement in the areas with opened trichome morphology.

Molecular imaging of cannabis leaf tissue with MeV-SIMS method

Energy Technology Data Exchange (ETDEWEB)

Jenčič, Boštjan, E-mail: bostjan.jencic@ijs.si [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Jeromel, Luka [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Ogrinc Potočnik, Nina [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); M4I, Maastricht University, Peter Debijelaan 25A, 6229 HX Maastricht (Netherlands); Vogel-Mikuš, Katarina [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); University of Ljubljana, Biotechnical Faculty, Dept. of Biology, Večna pot 11, SI-1000 Ljubljana (Slovenia); Kovačec, Eva; Regvar, Marjana [University of Ljubljana, Biotechnical Faculty, Dept. of Biology, Večna pot 11, SI-1000 Ljubljana (Slovenia); Siketić, Zdravko [Ruđer Bošković Institute, P.O. Box 180, 10000 Zagreb (Croatia); Vavpetič, Primož; Rupnik, Zdravko; Bučar, Klemen; Kelemen, Mitja; Kovač, Janez; Pelicon, Primož [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia)

2016-03-15

To broaden our analytical capabilities with molecular imaging in addition to the existing elemental imaging with micro-PIXE, a linear Time-Of-Flight mass spectrometer for MeV Secondary Ion Mass Spectrometry (MeV-SIMS) was constructed and added to the existing nuclear microprobe at the Jožef Stefan Institute. We measured absolute molecular yields and damage cross-section of reference materials, without significant alteration of the fragile biological samples during the duration of measurements in the mapping mode. We explored the analytical capability of the MeV-SIMS technique for chemical mapping of the plant tissue of medicinal cannabis leaves. A series of hand-cut plant tissue slices were prepared by standard shock-freezing and freeze-drying protocol and deposited on the Si wafer. We show the measured MeV-SIMS spectra showing a series of peaks in the mass area of cannabinoids, as well as their corresponding maps. The indicated molecular distributions at masses of 345.5 u and 359.4 u may be attributed to the protonated THCA and THCA-C4 acids, and show enhancement in the areas with opened trichome morphology.

Molecular imaging of cannabis leaf tissue with MeV-SIMS method

International Nuclear Information System (INIS)

Jenčič, Boštjan; Jeromel, Luka; Ogrinc Potočnik, Nina; Vogel-Mikuš, Katarina; Kovačec, Eva; Regvar, Marjana; Siketić, Zdravko; Vavpetič, Primož; Rupnik, Zdravko; Bučar, Klemen; Kelemen, Mitja; Kovač, Janez; Pelicon, Primož

2016-01-01

To broaden our analytical capabilities with molecular imaging in addition to the existing elemental imaging with micro-PIXE, a linear Time-Of-Flight mass spectrometer for MeV Secondary Ion Mass Spectrometry (MeV-SIMS) was constructed and added to the existing nuclear microprobe at the Jožef Stefan Institute. We measured absolute molecular yields and damage cross-section of reference materials, without significant alteration of the fragile biological samples during the duration of measurements in the mapping mode. We explored the analytical capability of the MeV-SIMS technique for chemical mapping of the plant tissue of medicinal cannabis leaves. A series of hand-cut plant tissue slices were prepared by standard shock-freezing and freeze-drying protocol and deposited on the Si wafer. We show the measured MeV-SIMS spectra showing a series of peaks in the mass area of cannabinoids, as well as their corresponding maps. The indicated molecular distributions at masses of 345.5 u and 359.4 u may be attributed to the protonated THCA and THCA-C4 acids, and show enhancement in the areas with opened trichome morphology.

Meshless methods in biomechanics bone tissue remodelling analysis

CERN Document Server

Belinha, Jorge

2014-01-01

This book presents the complete formulation of a new advanced discretization meshless technique: the Natural Neighbour Radial Point Interpolation Method (NNRPIM). In addition, two of the most popular meshless methods, the EFGM and the RPIM, are fully presented. Being a truly meshless method, the major advantages of the NNRPIM over the FEM, and other meshless methods, are the remeshing flexibility and the higher accuracy of the obtained variable field. Using the natural neighbour concept, the NNRPIM permits to determine organically the influence-domain, resembling the cellulae natural behaviour. This innovation permits the analysis of convex boundaries and extremely irregular meshes, which is an advantage in the biomechanical analysis, with no extra computational effort associated.   This volume shows how to extend the NNRPIM to the bone tissue remodelling analysis, expecting to contribute with new numerical tools and strategies in order to permit a more efficient numerical biomechanical analysis.

A study of muscular tissue of animal origin by reflection-spectroscopy methods

Science.gov (United States)

Plotnikova, L. V.; Nechiporenko, A. P.; Orekhova, S. M.; Plotnikov, P. P.; Ishevskii, A. L.

2017-06-01

A comparative analysis of the spectral characteristics of the surface of muscular tissue of animal origin (pork) and its main components has been performed by the methods of diffuse reflection electronic spectroscopy (DRES) and frustrated total internal reflection IR spectroscopy. The experiments have shown that the application of the DRES method makes it possible to detect more pronounced changes in the surface optical characteristics of muscular tissue and obtain electronic spectra containing information about the component composition of its main parts under successive extraction of sarcoplasmic materials, myofibrillar proteins of the actomyosin complex, and stroma mucopolysaccharides.

Method for Preparation of Amides from Alcohols and Amines by Extrusion of Hydrogen

DEFF Research Database (Denmark)

2010-01-01

The present invention relates to a method for preparation of carboxamides using alcohols and amines as starting materials in a dehydrogenative coupling reaction catalyzed by a ruthenium N-heterocyciic carbene (NHC) complex, which may be prepared in situ....

Comparison of commercial DNA preparation kits for the detection of Brucellae in tissue using quantitative real-time PCR

Directory of Open Access Journals (Sweden)

Straube Eberhard

2010-04-01

Full Text Available Abstract Background The detection of Brucellae in tissue specimens using PCR assays is difficult because the amount of bacteria is usually low. Therefore, optimised DNA extraction methods are critical. The aim of this study was to assess the performance of commercial kits for the extraction of Brucella DNA. Methods Five kits were evaluated using clinical specimens: QIAamp™ DNA Mini Kit (QIAGEN, peqGold™ Tissue DNA Mini Kit (PeqLab, UltraClean™ Tissue and Cells DNA Isolation Kit (MoBio, DNA Isolation Kit for Cells and Tissues (Roche, and NucleoSpin™ Tissue (Macherey-Nagel. DNA yield was determined using a quantitative real-time PCR assay targeting IS711 that included an internal amplification control. Results Kits of QIAGEN and Roche provided the highest amount of DNA, Macherey-Nagel and Peqlab products were intermediate whereas MoBio yielded the lowest amount of DNA. Differences were significant (p Conclusions We observed differences in DNA yield as high as two orders of magnitude for some samples between the best and the worst DNA extraction kits and inhibition was observed occasionally. This indicates that DNA purification may be more relevant than expected when the amount of DNA in tissue is very low.

A new construction technique for tissue-engineered heart valves using the self-assembly method.

Science.gov (United States)

Tremblay, Catherine; Ruel, Jean; Bourget, Jean-Michel; Laterreur, Véronique; Vallières, Karine; Tondreau, Maxime Y; Lacroix, Dan; Germain, Lucie; Auger, François A

2014-11-01

Tissue engineering appears as a promising option to create new heart valve substitutes able to overcome the serious drawbacks encountered with mechanical substitutes or tissue valves. The objective of this article is to present the construction method of a new entirely biological stentless aortic valve using the self-assembly method and also a first assessment of its behavior in a bioreactor when exposed to a pulsatile flow. A thick tissue was created by stacking several fibroblast sheets produced with the self-assembly technique. Different sets of custom-made templates were designed to confer to the thick tissue a three-dimensional (3D) shape similar to that of a native aortic valve. The construction of the valve was divided in two sequential steps. The first step was the installation of the thick tissue in a flat preshaping template followed by a 4-week maturation period. The second step was the actual cylindrical 3D forming of the valve. The microscopic tissue structure was assessed using histological cross sections stained with Masson's Trichrome and Picrosirius Red. The thick tissue remained uniformly populated with cells throughout the construction steps and the dense extracellular matrix presented corrugated fibers of collagen. This first prototype of tissue-engineered heart valve was installed in a bioreactor to assess its capacity to sustain a light pulsatile flow at a frequency of 0.5 Hz. Under the light pulsed flow, it was observed that the leaflets opened and closed according to the flow variations. This study demonstrates that the self-assembly method is a viable option for the construction of complex 3D shapes, such as heart valves, with an entirely biological material.

Study on fluorouracil–chitosan nanoparticle preparation and its antitumor effect

Directory of Open Access Journals (Sweden)

Gaimin Chen

2016-05-01

Full Text Available To successfully prepare fluorouracil–chitosan nanoparticles, and further analyze its anti-tumor activity mechanism, this paper makes a comprehensive study of existing preparation prescription and makes a detailed analysis of fluorouracil–chitosan in vitro release and pharmacodynamic behavior of animals. Two-step synthesis method is adopted to prepare 5-FU–CS–mPEG prodrugs, and infrared, 1H NMR and differential thermal analysis are adopted to analyze characterization synthetic products of prepared drugs. To ensure clinical efficacy of prepared drugs, UV spectrophotometry is adopted for determination of drug loading capacity of prepared drugs, transmission electron microscopy is adopted to observe the appearance, dynamic dialysis method is used to observe in vitro drug release of prepared drugs and fitting of various release models is done. Anti-tumor effect is studied via level of animal pharmacodynamics. After the end of the experiment, tumor inhibition rate, spleen index and thymus index of drugs are calculated. Experimental results show that the prepared drugs are qualified in terms of regular shape, dispersion, drug content, etc. Animal pharmacodynamics experiments have shown that concentration level of drug loading capacity of prepared drugs has a direct impact on anti-tumor rate. The higher the concentration, the higher the anti-tumor rate. Results of pathological tissue sections of mice show that the prepared drugs cause varying degrees of damage to receptor cells, resulting in cell necrosis or apoptosis problem. It can thus be concluded that ion gel method is an effective method to prepare drug-loading nanoparticles, with prepared nanoparticles evenly distributed in regular shape which demonstrate good slow-release characteristics in receptor vitro and vivo. At the same time, after completion of drug preparation, relatively strong anti-tumor activity can be generated for the receptor, so this mode of preparation enjoys broad

A new tissue segmentation method to calculate 3D dose in small animal radiation therapy.

Science.gov (United States)

Noblet, C; Delpon, G; Supiot, S; Potiron, V; Paris, F; Chiavassa, S

2018-02-26

In pre-clinical animal experiments, radiation delivery is usually delivered with kV photon beams, in contrast to the MV beams used in clinical irradiation, because of the small size of the animals. At this medium energy range, however, the contribution of the photoelectric effect to absorbed dose is significant. Accurate dose calculation therefore requires a more detailed tissue definition because both density (ρ) and elemental composition (Z eff ) affect the dose distribution. Moreover, when applied to cone beam CT (CBCT) acquisitions, the stoichiometric calibration of HU becomes inefficient as it is designed for highly collimated fan beam CT acquisitions. In this study, we propose an automatic tissue segmentation method of CBCT imaging that assigns both density (ρ) and elemental composition (Z eff ) in small animal dose calculation. The method is based on the relationship found between CBCT number and ρ*Z eff product computed from known materials. Monte Carlo calculations were performed to evaluate the impact of ρZ eff variation on the absorbed dose in tissues. These results led to the creation of a tissue database composed of artificial tissues interpolated from tissue values published by the ICRU. The ρZ eff method was validated by measuring transmitted doses through tissue substitute cylinders and a mouse with EBT3 film. Measurements were compared to the results of the Monte Carlo calculations. The study of the impact of ρZ eff variation over the range of materials, from ρZ eff  = 2 g.cm - 3 (lung) to 27 g.cm - 3 (cortical bone) led to the creation of 125 artificial tissues. For tissue substitute cylinders, the use of ρZ eff method led to maximal and average relative differences between the Monte Carlo results and the EBT3 measurements of 3.6% and 1.6%. Equivalent comparison for the mouse gave maximal and average relative differences of 4.4% and 1.2%, inside the 80% isodose area. Gamma analysis led to a 94.9% success rate in the 10% isodose

Fluidics platform and method for sample preparation and analysis

Science.gov (United States)

Benner, W. Henry; Dzenitis, John M.; Bennet, William J.; Baker, Brian R.

2014-08-19

Herein provided are fluidics platform and method for sample preparation and analysis. The fluidics platform is capable of analyzing DNA from blood samples using amplification assays such as polymerase-chain-reaction assays and loop-mediated-isothermal-amplification assays. The fluidics platform can also be used for other types of assays and analyzes. In some embodiments, a sample in a sealed tube can be inserted directly. The following isolation, detection, and analyzes can be performed without a user's intervention. The disclosed platform may also comprises a sample preparation system with a magnetic actuator, a heater, and an air-drying mechanism, and fluid manipulation processes for extraction, washing, elution, assay assembly, assay detection, and cleaning after reactions and between samples.

Preparation of Stable Amyloid-β Oligomers Without Perturbative Methods.

Science.gov (United States)

Kotler, Samuel A; Ramamoorthy, Ayyalusamy

2018-01-01

Soluble amyloid-β (Aβ) oligomers have become a focal point in the study of Alzheimer's disease due to their ability to elicit cytotoxicity. A number of recent studies have concentrated on the structural characterization of soluble Aβ oligomers to gain insight into their mechanism of toxicity. Consequently, providing reproducible protocols for the preparation of such oligomers is of utmost importance. The method presented in this chapter details a protocol for preparing an Aβ oligomer, with a primarily disordered secondary structure, without the need for chemical modification or amino acid substitution. Due to the stability of these disordered Aβ oligomers and the reproducibility with which they form, they are amenable for biophysical and high-resolution structural characterization.

Magnetic hyperthermia heating of cobalt ferrite nanoparticles prepared by low temperature ferrous sulfate based method

Directory of Open Access Journals (Sweden)

Tejabhiram Yadavalli

2016-05-01

Full Text Available A facile low temperature co-precipitation method for the synthesis of crystalline cobalt ferrite nanostructures using ferrous sulfate salt as the precursor has been discussed. The prepared samples were compared with nanoparticles prepared by conventional co-precipitation and hydrothermal methods using ferric nitrate as the precursor. X-ray diffraction studies confirmed the formation of cubic spinel cobalt ferrites when dried at 110 °C as opposed to conventional methods which required higher temperatures/pressure for the formation of the same. Field emission scanning electron microscope studies of these powders revealed the formation of nearly spherical nanostructures in the size range of 20-30 nm which were comparable to those prepared by conventional methods. Magnetic measurements confirmed the ferromagnetic nature of the cobalt ferrites with low magnetic remanance. Further magnetic hyperthermia studies of nanostructures prepared by low temperature method showed a rise in temperature to 50 °C in 600 s.

Preparation of YBCO superconducting films by spray pyrolysis method

International Nuclear Information System (INIS)

Mora Alonso, M.; Leyva Fabelo, A.; Rubio Frias, E.; Pupo Gonzalez, I.; Lopez Sanchez, D.

1994-01-01

The methodology for the preparation of YBCO superconducting films on Zr 2O (Y) substrates by spray pyrolysis method is reported. The transition temperature of these films is superior than the boiling temperature of liquid 2N . Other critical parameters are similar to those reported by other authors using the same technique

Preparation and studies of Co(II) and Co(III)-substituted barium ferrite prepared by sol-gel method

Energy Technology Data Exchange (ETDEWEB)

Teh, Geok Bee [Department of Bioscience and Chemistry, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, 53300 Kuala Lumpur (Malaysia)]. E-mail: tehgb@mail.utar.edu.my; Nagalingam, Saravanan [Department of Bioscience and Chemistry, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, 53300 Kuala Lumpur (Malaysia); Jefferson, David A. [Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (United Kingdom)

2007-01-15

The sol-gel preparative method was employed to synthesise Co(II) and Co(III)-substituted barium ferrite. This method was attempted to achieve higher homogeneity of the final product. Samples of substituted ferrites were characterised by various experimental techniques including high resolution transmission electron microscopy, X-ray diffraction analysis, magnetometry and thermal gravimetric analysis. The microstructural changes induced by such substitution are also discussed.

Preparation and studies of Co(II) and Co(III)-substituted barium ferrite prepared by sol-gel method

International Nuclear Information System (INIS)

Teh, Geok Bee; Nagalingam, Saravanan; Jefferson, David A.

2007-01-01

The sol-gel preparative method was employed to synthesise Co(II) and Co(III)-substituted barium ferrite. This method was attempted to achieve higher homogeneity of the final product. Samples of substituted ferrites were characterised by various experimental techniques including high resolution transmission electron microscopy, X-ray diffraction analysis, magnetometry and thermal gravimetric analysis. The microstructural changes induced by such substitution are also discussed

Preparation of uniform porous hydroxyapatite biomaterials by a new method

International Nuclear Information System (INIS)

Tang Yuejun; Tang Yuefeng; Lv Chuntang; Zhou Zhonghua

2008-01-01

In this paper, a new method of preparation of uniform porous hydroxyapatite biomaterials was reported. In order to obtain uniform porous biomaterials, disk samples were formed by the mixture of hydroxyapatite (HAP) powders and monodispersed polystyrene microspheres, and then HAP uniform porous materials with different diameter and different porosity (diameter: 436 ± 25 nm, 892 ± 20 nm and 1890 ± 20 nm, porosity: 46.5%, 41.3% and 34.7%, respectively) were prepared by sintering these disk samples at 1250 deg. C for 5 h. The pure phase of HAP powders fabricated by the hydrothermal technology was confirmed by X-ray diffraction (XRD). The surface and size distribution of pores in HAP biomaterials were observed by scanning electron microscopy (SEM), and the pore size distribution in porous HAP biomaterials was tested by mercury intrusion method

A novel method for preparation of HAMLET-like protein complexes.

Science.gov (United States)

Permyakov, Sergei E; Knyazeva, Ekaterina L; Leonteva, Marina V; Fadeev, Roman S; Chekanov, Aleksei V; Zhadan, Andrei P; Håkansson, Anders P; Akatov, Vladimir S; Permyakov, Eugene A

2011-09-01

Some natural proteins induce tumor-selective apoptosis. α-Lactalbumin (α-LA), a milk calcium-binding protein, is converted into an antitumor form, called HAMLET/BAMLET, via partial unfolding and association with oleic acid (OA). Besides triggering multiple cell death mechanisms in tumor cells, HAMLET exhibits bactericidal activity against Streptococcus pneumoniae. The existing methods for preparation of active complexes of α-LA with OA employ neutral pH solutions, which greatly limit water solubility of OA. Therefore these methods suffer from low scalability and/or heterogeneity of the resulting α-LA - OA samples. In this study we present a novel method for preparation of α-LA - OA complexes using alkaline conditions that favor aqueous solubility of OA. The unbound OA is removed by precipitation under acidic conditions. The resulting sample, bLA-OA-45, bears 11 OA molecules and exhibits physico-chemical properties similar to those of BAMLET. Cytotoxic activities of bLA-OA-45 against human epidermoid larynx carcinoma and S. pneumoniae D39 cells are close to those of HAMLET. Treatment of S. pneumoniae with bLA-OA-45 or HAMLET induces depolarization and rupture of the membrane. The cells are markedly rescued from death upon pretreatment with an inhibitor of Ca(2+) transport. Hence, the activation mechanisms of S. pneumoniae death are analogous for these two complexes. The developed express method for preparation of active α-LA - OA complex is high-throughput and suited for development of other protein complexes with low-molecular-weight amphiphilic substances possessing valuable cytotoxic properties. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Electron probe microanalysis for clinical investigations: Microdrop and soft tissue analysis

International Nuclear Information System (INIS)

Ingram, M.J.; Ingram, F.D.

1984-01-01

The most important advantage offered by electron probe microanalysis (EPA) for clinical investigations is the ability to analyze smaller volumes of tissue than is possible with conventional techniques. The sample can be a biological soft tissue specimen, which involves subcellular localization, or a picoliter fluid droplet. In either case, the analysis can be nondestructive and permit multiple analyses for a number of elements in a given sample. The most highly developed electron microprobe analytical technique is fluid drop analysis, popularly referred to as microdrop analysis. This method provides the investigator with an analytic capability that has an accuracy of measurement often 1% or better on 20 to 30 picoliter fluid droplets. Electron microprobe techniques have been used for studies of animal hard tissue and for studies that involve insoluble inclusions. However, the development of techniques for studies of labile constituents in animal soft tissue has been much slower. It has been necessary not only to develop appropriate methods of tissue preparation, but also to establish sound techniques for tissue collection. Although there are adequate methods for collection of most types of tissue from laboratory animals, many of these methods are not suitable for human subjects. In order to provide the reader with a better understanding of the capabilities and potential for the application of electron microprobe methodology to problems in clinical medicine, the authors discuss some of their experiences with liquid droplet analysis and quantitative electrolyte distribution measurements in animal soft tissue

Face-based smoothed finite element method for real-time simulation of soft tissue

Science.gov (United States)

Mendizabal, Andrea; Bessard Duparc, Rémi; Bui, Huu Phuoc; Paulus, Christoph J.; Peterlik, Igor; Cotin, Stéphane

2017-03-01

In soft tissue surgery, a tumor and other anatomical structures are usually located using the preoperative CT or MR images. However, due to the deformation of the concerned tissues, this information suffers from inaccuracy when employed directly during the surgery. In order to account for these deformations in the planning process, the use of a bio-mechanical model of the tissues is needed. Such models are often designed using the finite element method (FEM), which is, however, computationally expensive, in particular when a high accuracy of the simulation is required. In our work, we propose to use a smoothed finite element method (S-FEM) in the context of modeling of the soft tissue deformation. This numerical technique has been introduced recently to overcome the overly stiff behavior of the standard FEM and to improve the solution accuracy and the convergence rate in solid mechanics problems. In this paper, a face-based smoothed finite element method (FS-FEM) using 4-node tetrahedral elements is presented. We show that in some cases, the method allows for reducing the number of degrees of freedom, while preserving the accuracy of the discretization. The method is evaluated on a simulation of a cantilever beam loaded at the free end and on a simulation of a 3D cube under traction and compression forces. Further, it is applied to the simulation of the brain shift and of the kidney's deformation. The results demonstrate that the method outperforms the standard FEM in a bending scenario and that has similar accuracy as the standard FEM in the simulations of the brain-shift and of the kidney's deformation.

Intestinal preparation for colon enema with fosfo-soda fleet versus the conventional method

International Nuclear Information System (INIS)

Vecchioli Caldazza, A.; Celi, G.; De Franco, A.; Parrella, A.; Minordi, L.M.; Marano, P.

1999-01-01

The authors evaluate the possible optimization of a well-tolerated and versatile method of intestinal preparation able to adequately free the lumen and consequently improve diagnostic results with a lower risk of prolonged hospital stay for incorrectly prepared patients. They examined 40 patients, namely 20 men and 20 women referred to the Institute of radiology of the 'Sacro Cuore' Catholic University of Rome (Italy), Gastrointestinal tract unit, to undergo double contrast colonic enema. The statistical analysis of all data was performed with Wilcoxon test. Intestinal preparation with fosfo-soda fleet appeared to be definitely better than the conventional method relative to tolerance, while providing similarly satisfactory data relative to the other parameters [it

Complete solubilization of formalin-fixed, paraffin-embedded tissue may improve proteomic studies.

Science.gov (United States)

Shi, Shan-Rong; Taylor, Clive R; Fowler, Carol B; Mason, Jeffrey T

2013-04-01

Tissue-based proteomic approaches (tissue proteomics) are essential for discovering and evaluating biomarkers for personalized medicine. In any proteomics study, the most critical issue is sample extraction and preparation. This problem is especially difficult when recovering proteins from formalin-fixed, paraffin-embedded (FFPE) tissue sections. However, improving and standardizing protein extraction from FFPE tissue is a critical need because of the millions of archival FFPE tissues available in tissue banks worldwide. Recent progress in the application of heat-induced antigen retrieval principles for protein extraction from FFPE tissue has resulted in a number of published FFPE tissue proteomics studies. However, there is currently no consensus on the optimal protocol for protein extraction from FFPE tissue or accepted standards for quantitative evaluation of the extracts. Standardization is critical to ensure the accurate evaluation of FFPE protein extracts by proteomic methods such as reverse phase protein arrays, which is now in clinical use. In our view, complete solubilization of FFPE tissue samples is the best way to achieve the goal of standardizing the recovery of proteins from FFPE tissues. However, further studies are recommended to develop standardized protein extraction methods to ensure quantitative and qualitative reproducibility in the recovery of proteins from FFPE tissues. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Standard methods for sampling and sample preparation for gamma spectroscopy

International Nuclear Information System (INIS)

Taskaeva, M.; Taskaev, E.; Nikolov, P.

1993-01-01

The strategy for sampling and sample preparation is outlined: necessary number of samples; analysis and treatment of the results received; quantity of the analysed material according to the radionuclide concentrations and analytical methods; the minimal quantity and kind of the data needed for making final conclusions and decisions on the base of the results received. This strategy was tested in gamma spectroscopic analysis of radionuclide contamination of the region of Eleshnitsa Uranium Mines. The water samples was taken and stored according to the ASTM D 3370-82. The general sampling procedures were in conformity with the recommendations of ISO 5667. The radionuclides was concentrated by coprecipitation with iron hydroxide and ion exchange. The sampling of soil samples complied with the rules of ASTM C 998, and their sample preparation - with ASTM C 999. After preparation the samples were sealed hermetically and measured. (author)

[Sample preparation methods for chromatographic analysis of organic components in atmospheric particulate matter].

Science.gov (United States)

Hao, Liang; Wu, Dapeng; Guan, Yafeng

2014-09-01

The determination of organic composition in atmospheric particulate matter (PM) is of great importance in understanding how PM affects human health, environment, climate, and ecosystem. Organic components are also the scientific basis for emission source tracking, PM regulation and risk management. Therefore, the molecular characterization of the organic fraction of PM has become one of the priority research issues in the field of environmental analysis. Due to the extreme complexity of PM samples, chromatographic methods have been the chief selection. The common procedure for the analysis of organic components in PM includes several steps: sample collection on the fiber filters, sample preparation (transform the sample into a form suitable for chromatographic analysis), analysis by chromatographic methods. Among these steps, the sample preparation methods will largely determine the throughput and the data quality. Solvent extraction methods followed by sample pretreatment (e. g. pre-separation, derivatization, pre-concentration) have long been used for PM sample analysis, and thermal desorption methods have also mainly focused on the non-polar organic component analysis in PM. In this paper, the sample preparation methods prior to chromatographic analysis of organic components in PM are reviewed comprehensively, and the corresponding merits and limitations of each method are also briefly discussed.

Methods of preparing and using intravenous nutrient compositions

International Nuclear Information System (INIS)

Beigler, M.A.; Koury, A.J.

1983-01-01

A method for preparing a stable, dry-packaged, sterile, nutrient composition which upon addition of sterile, pyrogen-free water is suitable for intravenous administration to a mammal, including a human, is described. The method comprises providing the nutrients in a specific dry form and state of physical purity acceptable for intravenous administration, sealing the nutrients in a particular type of container adapted to receive and dispense sterile fluids and subjecting the container and its sealed contents to a sterilizing, nondestructive dose of ionizing radiation. The method results in a packaged, sterile nutrient composition which may be dissolved by the addition of sterile pyrogen-free water. The resulting aqueous intravenous solution may be safely administered to a mammal in need of nutrient therapy. The packaged nutrient compositions of the invention exhibit greatly extended storage life and provide an economical method of providing intravenous solutions which are safe and efficacious for use. (author)

A Tissue Relevance and Meshing Method for Computing Patient-Specific Anatomical Models in Endoscopic Sinus Surgery Simulation

Science.gov (United States)

Audette, M. A.; Hertel, I.; Burgert, O.; Strauss, G.

This paper presents on-going work on a method for determining which subvolumes of a patient-specific tissue map, extracted from CT data of the head, are relevant to simulating endoscopic sinus surgery of that individual, and for decomposing these relevant tissues into triangles and tetrahedra whose mesh size is well controlled. The overall goal is to limit the complexity of the real-time biomechanical interaction while ensuring the clinical relevance of the simulation. Relevant tissues are determined as the union of the pathology present in the patient, of critical tissues deemed to be near the intended surgical path or pathology, and of bone and soft tissue near the intended path, pathology or critical tissues. The processing of tissues, prior to meshing, is based on the Fast Marching method applied under various guises, in a conditional manner that is related to tissue classes. The meshing is based on an adaptation of a meshing method of ours, which combines the Marching Tetrahedra method and the discrete Simplex mesh surface model to produce a topologically faithful surface mesh with well controlled edge and face size as a first stage, and Almost-regular Tetrahedralization of the same prescribed mesh size as a last stage.

[Standard sample preparation method for quick determination of trace elements in plastic].

Science.gov (United States)

Yao, Wen-Qing; Zong, Rui-Long; Zhu, Yong-Fa

2011-08-01

Reference sample was prepared by masterbatch method, containing heavy metals with known concentration of electronic information products (plastic), the repeatability and precision were determined, and reference sample preparation procedures were established. X-Ray fluorescence spectroscopy (XRF) analysis method was used to determine the repeatability and uncertainty in the analysis of the sample of heavy metals and bromine element. The working curve and the metrical methods for the reference sample were carried out. The results showed that the use of the method in the 200-2000 mg x kg(-1) concentration range for Hg, Pb, Cr and Br elements, and in the 20-200 mg x kg(-1) range for Cd elements, exhibited a very good linear relationship, and the repeatability of analysis methods for six times is good. In testing the circuit board ICB288G and ICB288 from the Mitsubishi Heavy Industry Company, results agreed with the recommended values.

Preparation of CaSO4:Dy by precipitation method to gamma radiation dosimetry

International Nuclear Information System (INIS)

Rivera, T.; Roman, J.; Azorin, J.; Sosa, R.; Guzman, J.; Serrano, A.K.; Garcia, M.; Alarcon, G.

2010-01-01

This paper presents the results of the preparation and characterization of dysprosium-doped calcium sulfate (CaSO 4 :Dy) phosphor, which was obtained by homogeneous precipitation from calcium acetate Ca(CH 3 COO - ) 2 . Structural and morphological characteristics were studied using a scanning electronic microscope (SEM). The structure of all compounds was determined by X-ray diffraction method too. Thermoluminescence (TL) emission properties of CaSO 4 :Dy under gamma radiation effects were studied. This phosphor powder presented a TL glow curve with two peaks (Tmax) centered at around of 180 and 300 deg. C, respectively. The TL response of CaSO 4 :Dy as a function of gamma absorbed dose was linear in a wide range. Both emission and excitation spectra were also obtained. Results showed that this new preparation method of CaSO 4 :Dy TL phosphor is less expensive, cleaner and safer than the conventional preparation method.

Method for estimating optimal spectral and energy parameters of laser irradiation in photodynamic therapy of biological tissue

Energy Technology Data Exchange (ETDEWEB)

Lisenko, S A; Kugeiko, M M [Belarusian State University, Minsk (Belarus)

2015-04-30

We have solved the problem of layer-by-layer laser-light dosimetry in biological tissues and of selecting an individual therapeutic dose in laser therapy. A method is proposed for real-time monitoring of the radiation density in tissue layers in vivo, concentrations of its endogenous (natural) and exogenous (specially administered) chromophores, as well as in-depth distributions of the spectrum of light action on these chromophores. As the background information use is made of the spectrum of diffuse light reflected from a patient's tissue, measured by a fibre-optic spectrophotometer. The measured spectrum is quantitatively analysed by the method of approximating functions for fluxes of light multiply scattered in tissue and by a semi-analytical method for calculating the in-depth distribution of the light flux in a multi-layered medium. We have shown the possibility of employing the developed method for monitoring photosensitizer and oxyhaemoglobin concentrations in tissue, light power absorbed by chromophores in tissue layers at different depths and laser-induced changes in the tissue morphology (vascular volume content and ratios of various forms of haemoglobin) during photodynamic therapy. (biophotonics)

The surrounding tissue modifies the placental stem villous vascular responses

DEFF Research Database (Denmark)

Brøgger, Torbjørn; Forman, Axel; Aalkjær, Christian

2014-01-01

is available. In-depth understanding of the mechanisms involved in control of placental vascular tone are needed to develop new tissue targets for therapeutic intervention. Method: From fresh born placentas segments of stem villous arteries were carefully dissected. The artery branches were divided....... The surrounding trophoblast was removed from one end and left intact in the other, and the segment was divided to give two ring preparations, with or without trophoblast. The preparations were mounted in wire myographs and responses to vasoactive agents were compared. Results: pD2values for PGF2α, Tx-analog U...... or endotheline-1. These differences partly disappeared in the presence of L-NAME. Conclusion: The perivascular tissue significantly reduces sensitivity and force development of stem villous arteries, partly due to release of NO This represents a new mechanism for control of human stem villous artery tone....

A Novel Preparation Method of Two Polymer Dyes with Low Cytotoxicity

Directory of Open Access Journals (Sweden)

Dongjun Lv

2017-02-01

Full Text Available A new preparation method of polymer dyes was developed to improve both the grafting degree of the azo dyes onto O-carboxymethyl chitosan (OMCS and the water solubility of prepared polymer dyes. Firstly, the coupling compound of two azo edible colorants, sunset yellow (SY and allura red (AR, was grafted onto OMCS, and then coupled with their diazonium salt. The chemical structure of prepared polymer dyes was determined by Fourier transform-infrared spectroscopy and 1H-NMR, and the results showed that the two azo dyes were successfully grafted onto OMCS. The grafting degree onto OMCS and the water solubility of polymer dyes were tested, and the results showed that they were both improved as expected. The UV-vis spectra analysis results showed that the prepared polymer dyes showed similar color performance with the original azo dyes. Eventually, the cytotoxicity of prepared polymer dyes was tested and compared with the original azo dyes by a cytotoxicity test on human liver cell lines LO2, and the results showed that their grafting onto OMCS significantly reduced the cytotoxicity.

Preparation and characterization of carbon nanofibrous/hydroxyapatite sheets for bone tissue engineering.

Science.gov (United States)

Abd El-Aziz, A M; El Backly, Rania M; Taha, Nahla A; El-Maghraby, Azza; Kandil, Sherif H

2017-07-01

Critical size bone defects are orthopedic defects that will not heal without intervention or that will not completely heal over the natural life time of the animal. Although bone generally has the ability to regenerate completely however, critical defects require some sort of scaffold to do so. In the current study we proposed a method to obtain a carbon nanofibrous/Hydroxyapatite (HA) bioactive scaffold. The carbon nanofibrous (CNF) nonwoven fabrics were obtained by the use of the electrospinning process of the polymeric solution of poly acrylonitrile "PAN" and subsequent stabilization and carbonization processes. The CNFs sheets were functionalized by both hydroxyapatite (HA) and bovine serum albumin (BSA). The HA was added to the electrospun solution, but in case of (BSA), it was adsorbed after the carbonization process. The changes in the properties taking place in the precursor sheets were investigated using the characterization methods (SEM, FT-IR, TGA and EDX). The prepared materials were tested for biocompatibility via subcutaneous implantation in New Zealand white rabbits. We successfully prepared biocompatible functionalized sheets, which have been modified with HA or HA and BSA. The sheets that were functionalized by both HA and BSA are more biocompatible with fewer inflammatory cells of (neutrophils and lymphocytes) than ones with only HA over the period of 3weeks. Copyright © 2017 Elsevier B.V. All rights reserved.

Method for the preparation of carbon fiber from polyolefin fiber precursor

Energy Technology Data Exchange (ETDEWEB)

Naskar, Amit Kumar; Hunt, Marcus Andrew; Saito, Tomonori

2017-11-28

Methods for the preparation of carbon fiber from polyolefin fiber precursor, wherein the polyolefin fiber precursor is partially sulfonated and then carbonized to produce carbon fiber. Methods for producing hollow carbon fibers, wherein the hollow core is circular- or complex-shaped, are also described. Methods for producing carbon fibers possessing a circular- or complex-shaped outer surface, which may be solid or hollow, are also described.

Novel Method of Preparation and Activity Research on Arctigenin from Fructus Arctii

Science.gov (United States)

Cai, Enbo; Han, Jiahong; Yang, Limin; Zhang, Weiyuan; Zhao, Yan; Chen, Qiulian; Guo, Meng; He, Xinhong

2018-01-01

Background: Arctigenin has many pharmacological activities with clinical significance and is derived from Arctium lappa L. However, the present extraction method is inefficient and does not have meaningful industrial production. Objective: A new method to directly prepare arctigenin was established by combining enzyme-assisted extraction and central composite design. Arctigenin's further pharmacological activity was also surveyed in vitro. Materials and Methods: β-D-Glucosidase, a food-grade enzyme, was added directly to the fruits of A. lappa L. to hydrolyze the arctiin to arctigenin, and the obtained samples were subsequently subjected to ethanol (30%, v/v) extraction. The pharmacological activity of the extraction and arctigenin was determined by inhibiting acetylcholinesterase (AChE) and scavenging nitrite. Results: The factors investigated include the enzyme concentration (0.5%–2.5%), ultrasound time (10 min−3 0 min), and extraction temperature (30°C–50°C). From the analysis of the results by Design-Expert (V8.0.6), the optimal extraction conditions were obtained: enzyme concentration (1.4%), ultrasound time (25 min), and extraction temperature (45°C). The highest yield of arctigenin, obtained under the optimal conditions was 6.39%, representing an increase of 28.15% compared to the reference extraction without enzyme processing. The IC50 values of the extraction and arctigenin, respectively, for inhibiting AChE were 0.572 mg/ml and 0.462 mg/ml, and those for nitrite-scavenging were 34.571 mg/ml and 17.49 mg/ml. Conclusions: The results demonstrate that using an enzyme directly in the production is an effective means for extracting arctigenin from Fructus arctii. The extraction has the activities of inhibiting AChE and scavenging nitrite, probably because there has arctigenin in it. It is implied that the extraction and arctigenin could contribute to human health in clinical applications. SUMMARY The new method of adding enzyme directly to the

Effective atomic numbers of some tissue substitutes by different methods: A comparative study

Directory of Open Access Journals (Sweden)

Vishwanath P Singh

2014-01-01

Full Text Available Effective atomic numbers of some human organ tissue substitutes such as polyethylene terephthalate, red articulation wax, paraffin 1, paraffin 2, bolus, pitch, polyphenylene sulfide, polysulfone, polyvinylchloride, and modeling clay have been calculated by four different methods like Auto-Z eff, direct, interpolation, and power law. It was found that the effective atomic numbers computed by Auto-Z eff , direct and interpolation methods were in good agreement for intermediate energy region (0.1 MeV < E < 5 MeV where the Compton interaction dominates. A large difference in effective atomic numbers by direct method and Auto-Z eff was observed in photo-electric and pair-production regions. Effective atomic numbers computed by power law were found to be close to direct method in photo-electric absorption region. The Auto-Z eff , direct and interpolation methods were found to be in good agreement for computation of effective atomic numbers in intermediate energy region (100 keV < E < 10 MeV. The direct method was found to be appropriate method for computation of effective atomic numbers in photo-electric region (10 keV < E < 100 keV. The tissue equivalence of the tissue substitutes is possible to represent by any method for computation of effective atomic number mentioned in the present study. An accurate estimation of Rayleigh scattering is required to eliminate effect of molecular, chemical, or crystalline environment of the atom for estimation of gamma interaction parameters.

Lambda-Cyhalothrin Nanosuspension Prepared by the Melt Emulsification-High Pressure Homogenization Method

OpenAIRE

Pan, Zhenzhong; Cui, Bo; Zeng, Zhanghua; Feng, Lei; Liu, Guoqiang; Cui, Haixin; Pan, Hongyu

2015-01-01

The nanosuspension of 5% lambda-cyhalothrin with 0.2% surfactants was prepared by the melt emulsification-high pressure homogenization method. The surfactants composition, content, and homogenization process were optimized. The anionic surfactant (1-dodecanesulfonic acid sodium salt) and polymeric surfactant (maleic rosin-polyoxypropylene-polyoxyethylene ether sulfonate) screened from 12 types of commercially common-used surfactants were used to prepare lambda-cyhalothrin nanosuspension with ...

Influence of tissue preservation methods on arterial geometry and echogenicity

DEFF Research Database (Denmark)

Wilhjelm, Jens Erik; Vogt, Katja; Jespersen, Søren Kragh

1997-01-01

Thoracic porcine aortas from 5 pigs were investigated with 7,5-MHz ultrasound in vitro at low and high transmural pressure before and after the following tissue preservation methods were applied: 1, Storage in frozen condition(-12 degrees C) for 24 h followed by thawing; 2, fixation in formalin...

Preparation, microstructure and properties of yttrium aluminum garnet fibers prepared by sol-gel method

Energy Technology Data Exchange (ETDEWEB)

Li Chengshun [Key Laboratory for Liquid Structure and Heredity of Materials of Ministry of Education, Shandong University, Jinan 250061 (China); Zhang Yujun [Key Laboratory for Liquid Structure and Heredity of Materials of Ministry of Education, Shandong University, Jinan 250061 (China)], E-mail: yujunzhangcn@sdu.edu.cn; Gong Hongyu; Zhang Jingde; Nie Lifang [Key Laboratory for Liquid Structure and Heredity of Materials of Ministry of Education, Shandong University, Jinan 250061 (China)

2009-01-15

Yttrium aluminum garnet (YAG) fiber was prepared by sol-gel method using water as the solvent. The spinnable YAG sol was synthesized using Al powder, Y(CH{sub 3}COOH){sub 3}.4H{sub 2}O and HCl as precursors, polyethylene oxide as viscosity adjusting agent. Gel fibers with diameter of 5-10 {mu}m were prepared from the YAG sol by using centrifugal spinning technique. YAG crystalline fibers were obtained by drying gel fibers and heat-treating at selected temperature. TG/DTA analysis showed an exotherm at 906 deg. C attributed to formation of YAG phase and weight loss of 45% at 1000 deg. C. XRD and FT-IR analysis showed that phase-pure YAG can be formed at 900 deg. C, and no other intermediate was observed. The grain size of YAG fibers increased from 25 to 220 nm and tensile strength decreased rapidly from 970 to 380 MPa when the sintering temperature increased from 900 to 1550 deg. C.

A Facile Method for the Preparation of Unsymmetrical Ureas Utilizing Zirconium(IV) Chloride

International Nuclear Information System (INIS)

Lee, Anna; Kim, Hee-Kwon; Thompson, David H.

2016-01-01

A facile synthetic method for the preparation of unsymmetrical ureas from amines is described.Carbamoyl imidazole compounds were prepared by the reaction of 1,1-carbonyldiimidazole with primary or secondary amines, and further activation by treatment with zirconium(IV) chloride to generate the desired urea. This reaction protocol was applied to the synthesis of tri and tetrasubstituted ureas with high yields. This study provides an alternative guideline for the practical preparation of various unsymmetrical ureas.

Preparation of protactinium measurement source by electroplating method

International Nuclear Information System (INIS)

Li Zongwei; Yang Weifan; Fang Keming; Yuan Shuanggui; Guo Junsheng; Pan Qiangyan

1998-01-01

An electroplating method for the preparation of Pa sources is described, and the main factors (such as pH value of solution, electroplating time and current density) influencing the electroplating of Pa are tested and discussed with 233 Pa as a tracer. A thin and uniform electroplating Pa-Layer of 1 mg/cm 2 thick on thin stainless steel disk was obtained. The Pa source was measured by a HPGe detector to determine the chemical efficiency

The effects of crosslinkers on physical, mechanical, and cytotoxic properties of gelatin sponge prepared via in-situ gas foaming method as a tissue engineering scaffold

Energy Technology Data Exchange (ETDEWEB)

Poursamar, S. Ali [Institute for Creative Leather Technologies, Park Campus, The University of Northampton, Boughton Green Road, Northampton NN2 7AL (United Kingdom); Lehner, Alexander N. [Centre for Physical Activity and Chronic Disease and the Aging Research Centre, Institute for Health and Wellbeing, School of Health, Park Campus, The University of Northampton, Boughton Green Road, Northampton NN2 7AL (United Kingdom); Azami, Mahmoud; Ebrahimi-Barough, Somayeh [Department of Tissue Engineering, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Samadikuchaksaraei, Ali [Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Medical Biotechnology, Faculty of Applied Medicine, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Antunes, A.P.M., E-mail: Paula.Antunes@northampton.ac.uk [Institute for Creative Leather Technologies, Park Campus, The University of Northampton, Boughton Green Road, Northampton NN2 7AL (United Kingdom)

2016-06-01

In this study porous gelatin scaffolds were prepared using in-situ gas foaming, and four crosslinking agents were used to determine a biocompatible and effective crosslinker that is suitable for such a method. Crosslinkers used in this study included: hexamethylene diisocyanate (HMDI), poly(ethylene glycol) diglycidyl ether (epoxy), glutaraldehyde (GTA), and genipin. The prepared porous structures were analyzed using Fourier Transform Infrared Spectroscopy (FT-IR), thermal and mechanical analysis as well as water absorption analysis. The microstructures of the prepared samples were analyzed using Scanning Electron Microscopy (SEM). The effects of the crosslinking agents were studied on the cytotoxicity of the porous structure indirectly using MTT analysis. The affinity of L929 mouse fibroblast cells for attachment on the scaffold surfaces was investigated by direct cell seeding and DAPI-staining technique. It was shown that while all of the studied crosslinking agents were capable of stabilizing prepared gelatin scaffolds, there are noticeable differences among physical and mechanical properties of samples based on the crosslinker type. Epoxy-crosslinked scaffolds showed a higher capacity for water absorption and more uniform microstructures than the rest of crosslinked samples, whereas genipin and GTA-crosslinked scaffolds demonstrated higher mechanical strength. Cytotoxicity analysis showed the superior biocompatibility of the naturally occurring genipin in comparison with other synthetic crosslinking agents, in particular relative to GTA-crosslinked samples. - Highlights: • In-situ gas foaming application in the production of sponge-like gelatin structures • The crosslinkers molecular length impacts on the physical and mechanical properties of the structure. • The effect of crosslinkers on the biocompatibility of gelatin scaffolds.

The effects of crosslinkers on physical, mechanical, and cytotoxic properties of gelatin sponge prepared via in-situ gas foaming method as a tissue engineering scaffold

International Nuclear Information System (INIS)

Poursamar, S. Ali; Lehner, Alexander N.; Azami, Mahmoud; Ebrahimi-Barough, Somayeh; Samadikuchaksaraei, Ali; Antunes, A.P.M.

2016-01-01

In this study porous gelatin scaffolds were prepared using in-situ gas foaming, and four crosslinking agents were used to determine a biocompatible and effective crosslinker that is suitable for such a method. Crosslinkers used in this study included: hexamethylene diisocyanate (HMDI), poly(ethylene glycol) diglycidyl ether (epoxy), glutaraldehyde (GTA), and genipin. The prepared porous structures were analyzed using Fourier Transform Infrared Spectroscopy (FT-IR), thermal and mechanical analysis as well as water absorption analysis. The microstructures of the prepared samples were analyzed using Scanning Electron Microscopy (SEM). The effects of the crosslinking agents were studied on the cytotoxicity of the porous structure indirectly using MTT analysis. The affinity of L929 mouse fibroblast cells for attachment on the scaffold surfaces was investigated by direct cell seeding and DAPI-staining technique. It was shown that while all of the studied crosslinking agents were capable of stabilizing prepared gelatin scaffolds, there are noticeable differences among physical and mechanical properties of samples based on the crosslinker type. Epoxy-crosslinked scaffolds showed a higher capacity for water absorption and more uniform microstructures than the rest of crosslinked samples, whereas genipin and GTA-crosslinked scaffolds demonstrated higher mechanical strength. Cytotoxicity analysis showed the superior biocompatibility of the naturally occurring genipin in comparison with other synthetic crosslinking agents, in particular relative to GTA-crosslinked samples. - Highlights: • In-situ gas foaming application in the production of sponge-like gelatin structures • The crosslinkers molecular length impacts on the physical and mechanical properties of the structure. • The effect of crosslinkers on the biocompatibility of gelatin scaffolds

A simple source preparation method for alpha-ray spectrometry of volcanic rock sample

International Nuclear Information System (INIS)

Takahashi, Masaomi; Kurihara, Yuichi; Sato, Jun

2006-01-01

A simple source preparation method was developed for the alpha-ray spectrometry to determine U and Th in volcanic rockes. Isolation of U and Th from volcanic rocks was made by use of UTEVA-Spec. resin, extraction chromatograph material. U and Th were extracted by TTA-benzene solution and organic phase was evaporated drop by drop on a hot stainless steel planchet to dryness. This method was found to be effective for the preparation of sources for alpha-ray spectrometry. (author)

Validity of a manual soft tissue profile prediction method following mandibular setback osteotomy.

Science.gov (United States)

Kolokitha, Olga-Elpis

2007-10-01

The aim of this study was to determine the validity of a manual cephalometric method used for predicting the post-operative soft tissue profiles of patients who underwent mandibular setback surgery and compare it to a computerized cephalometric prediction method (Dentofacial Planner). Lateral cephalograms of 18 adults with mandibular prognathism taken at the end of pre-surgical orthodontics and approximately one year after surgery were used. To test the validity of the manual method the prediction tracings were compared to the actual post-operative tracings. The Dentofacial Planner software was used to develop the computerized post-surgical prediction tracings. Both manual and computerized prediction printouts were analyzed by using the cephalometric system PORDIOS. Statistical analysis was performed by means of t-test. Comparison between manual prediction tracings and the actual post-operative profile showed that the manual method results in more convex soft tissue profiles; the upper lip was found in a more prominent position, upper lip thickness was increased and, the mandible and lower lip were found in a less posterior position than that of the actual profiles. Comparison between computerized and manual prediction methods showed that in the manual method upper lip thickness was increased, the upper lip was found in a more anterior position and the lower anterior facial height was increased as compared to the computerized prediction method. Cephalometric simulation of post-operative soft tissue profile following orthodontic-surgical management of mandibular prognathism imposes certain limitations related to the methods implied. However, both manual and computerized prediction methods remain a useful tool for patient communication.

Development and Physicochemical Characterization of Sirolimus Solid Dispersions Prepared by Solvent Evaporation Method

Directory of Open Access Journals (Sweden)

Shahram Emami

2014-12-01

Full Text Available Purpose: The aim of the present investigation was preparation and characterization of sirolimus solid dispersions by solvent evaporation technique to improve its dissolution properties. Methods: Polyvinylpyrrolidone (PVP, Poloxamer 188 and Cremophore RH40 were used to prepare the solid dispersions of sirolimus. In vitro dissolution study using USP type I apparatus, were performed in distilled water (containing SLS 0.4% for pure sirolimus, physical mixtures, Rapamune and prepared solid dispersions. The characterization of solid dispersions was performed using Fourier Transform Infrared (FTIR Spectroscopy and Differential Scanning Calorimetry (DSC. Results: More than 75% of sirolimus was released within 30 minutes from all prepared solid dispersions. The dissolution rate of all prepared solid dispersion powders were more than physical mixtures. The absence of sirolimus peak in the DSC spectrum of solid dispersions indicated the conversion of crystalline form of sirolimus into amorphous form. The results from FT-IR spectroscopy showed that there was no significant change in the FT-IR spectrum of solid dispersions indicating absence of well-defined interaction between drug and carriers. Conclusion: It was concluded that solid dispersion method, using PVP, Poloxamer 188 and Cremophore RH40 can improve dissolution rate of sirolimus.

Application of radiochemical methods for development of new biological preparation designed for soil bioremediation

International Nuclear Information System (INIS)

Kim, A.A.; Djuraeva, G.T.; Djumaniyazova, G.I.; Yadgarov, Kh.T.

2006-01-01

Full text: Internationally the bioremediation of agricultural lands contaminated by persistent chloroorganic compounds by means of the microbial methods are used as the most low-cost and the most effective. One of the factors reducing efficacy of microbial degradation, is often the low quantity of microorganisms - destructors in the soil. Therefore, we have designed bioremediation technology of soils, contaminated by organochlorine compounds, with use of the alive microorganisms as active agent. We developed the biological preparation containing 5 aboriginal active strains of bacteria - destructors of persistent chloroorganic compounds and investigated the ability of biological preparation to increase the bioremediation potential of contaminated soils. To carry out the investigation we developed the complex of radiochemical methods with use of tritium labeled PCBs, including the following methods: 1.The method to define the accumulation and degradation of PCBs in soil bacteria in culture allows determination of quantitative characteristics of bacterial strains. 2. The method to define the PCBs degradation by soil bacteria strains in model conditions in the soil allows to estimate the PCB-destructive activity of strains after introducing in soil. 3. A method to define the PCB-destructive activity of own microbiota of contaminated soil. 4. A method to define the effect of stimulation of the PCB-destructive activity of biological preparation and own microbiota of soil with the help of biofertilizers. By using the developed radiochemical methods we have carried out investigation on creation of new biological preparation on the basis of strains of soil bacteria - destructors of PCBs. We also determined the quality and quantity characteristics of HCCH and PCBs-destructive activity of new biological preparation. It is shown that the new biological preparation is capable of accumulation and destruction of the PCBs in culture and in soil at model conditions. Thus, the

Tissue microarrays and their use for preparation of reference slides ...

African Journals Online (AJOL)

Use of Tissue array was first applied in 1998, and has received a significant amount of attention from the research community ever since. In this technique, a large number (up to 1000) of cylindrical tissue core extracted from \\"donor\\" paraffin block are deposited into \\"recipient\\" block. The aim was modification of the ...

An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

Energy Technology Data Exchange (ETDEWEB)

Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

1997-11-01

This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

International Nuclear Information System (INIS)

Farace, Paolo; Antolini, Renzo; Pontalti, Rolando; Cristoforetti, Luca; Scarpa, Marina

1997-01-01

This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning.

Science.gov (United States)

Farace, P; Pontalti, R; Cristoforetti, L; Antolini, R; Scarpa, M

1997-11-01

This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning.

An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

Energy Technology Data Exchange (ETDEWEB)

Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

1997-11-01

This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

Particle induced x-ray emission (PIXE) measurement of the Cd content in animal tissues

International Nuclear Information System (INIS)

Le Huong Quynh; Demeter, I.; Hollos-Nagy, K.; Szoekefalvi-Nagy, Z.

1989-12-01

Particle induced x-ray emission (PIXE) measurements were performed on thin samples prepared from different rabbit tissues, using 3 MeV proton beam for inducing x-rays from the animal tissues. This method is very sensitive and very small amounts of trace elements can be detected. Cadmium, one of the most toxic elements which can be concentrated in animal and human tissues due to environmental pollution, was detected with a limit of 0.7 ppm. The trace element concentrations obtained by PIXE were compared to those measured by atomic absorption spectrometry. PIXE method is proposed for routine analysis at the Veterinary and Food Investigating Service, Budapest, Hungary. (D.Gy.) 6 refs.; 3 figs

Spatial cluster analysis of nanoscopically mapped serotonin receptors for classification of fixed brain tissue

Science.gov (United States)

Sams, Michael; Silye, Rene; Göhring, Janett; Muresan, Leila; Schilcher, Kurt; Jacak, Jaroslaw

2014-01-01

We present a cluster spatial analysis method using nanoscopic dSTORM images to determine changes in protein cluster distributions within brain tissue. Such methods are suitable to investigate human brain tissue and will help to achieve a deeper understanding of brain disease along with aiding drug development. Human brain tissue samples are usually treated postmortem via standard fixation protocols, which are established in clinical laboratories. Therefore, our localization microscopy-based method was adapted to characterize protein density and protein cluster localization in samples fixed using different protocols followed by common fluorescent immunohistochemistry techniques. The localization microscopy allows nanoscopic mapping of serotonin 5-HT1A receptor groups within a two-dimensional image of a brain tissue slice. These nanoscopically mapped proteins can be confined to clusters by applying the proposed statistical spatial analysis. Selected features of such clusters were subsequently used to characterize and classify the tissue. Samples were obtained from different types of patients, fixed with different preparation methods, and finally stored in a human tissue bank. To verify the proposed method, samples of a cryopreserved healthy brain have been compared with epitope-retrieved and paraffin-fixed tissues. Furthermore, samples of healthy brain tissues were compared with data obtained from patients suffering from mental illnesses (e.g., major depressive disorder). Our work demonstrates the applicability of localization microscopy and image analysis methods for comparison and classification of human brain tissues at a nanoscopic level. Furthermore, the presented workflow marks a unique technological advance in the characterization of protein distributions in brain tissue sections.

Advantages of infrared transflection micro spectroscopy and paraffin-embedded sample preparation for biological studies

Science.gov (United States)

Yao, Jie; Li, Qian; Zhou, Bo; Wang, Dan; Wu, Rie

2018-04-01

Fourier-Transform Infrared micro-spectroscopy is an excellent method for biological analyses. In this paper, series metal coating films on ITO glass were prepared by the electrochemical method and the different thicknesses of paraffin embedding rat's brain tissue on the substrates were studied by IR micro-spetroscopy in attenuated total reflection (ATR) mode and transflection mode respectively. The Co-Ni-Cu alloy coating film with low cost is good reflection substrates for the IR analysis. The infrared microscopic transflection mode needs not to touch the sample at all and can get the IR spectra with higher signal to noise ratios. The Paraffin-embedding method allows tissues to be stored for a long time for re-analysis to ensure the traceability of the sample. Also it isolates the sample from the metal and avoids the interaction of biological tissue with the metals. The best thickness of the tissues is 4 μm.

Reverse isotope dilution method for determining benzene and metabolites in tissues

International Nuclear Information System (INIS)

Bechtold, W.E.; Sabourin, P.J.; Henderson, R.F.

1988-01-01

A method utilizing reverse isotope dilution for the analysis of benzene and its organic soluble metabolites in tissues of rats and mice is presented. Tissues from rats and mice that had been exposed to radiolabeled benzene were extracted with ethyl acetate containing known, excess quantities of unlabeled benzene and metabolites. Butylated hydroxytoluene was added as an antioxidant. The ethyl acetate extracts were analyzed with semipreparative reversed-phase HPLC. Isolated peaks were collected and analyzed for radioactivity (by liquid scintillation spectrometry) and for mass (by UV absorption). The total amount of each compound present was calculated from the mass dilution of the radiolabeled isotope. This method has the advantages of high sensitivity, because of the high specific activity of benzene, and relative stability of the analyses, because of the addition of large amounts of unlabeled carrier analogue

Practical methods of target preparation for use in nuclear experiments

International Nuclear Information System (INIS)

Sugai, Isao.

1976-01-01

This is the fifth report on the practical methods of target preparation for use in nuclear experiments following the previous one (INS-J-152, 1975). Electro-deposition is a very powerful technique well suited to the preparation of self-supporting targets of Ni, Cr, Zn, Rh, Cd, Sb and Pb metals over a wide range of thickness from 1 to 20 mg/cm 2 . The uniformities of the thicknesses of Cr, Zn, Rh, Cd and Pb targets were measured with α- and β-ray thickness gauges. The impurities in Cr target were checked by the measurement of elastically scattered protons, and by a optical spectrometer. (auth.)

Research on the preparation, biocompatibility and bioactivity of magnesium matrix hydroxyapatite composite material.

Science.gov (United States)

Linsheng, Li; Guoxiang, Lin; Lihui, Li

2016-08-12

In this paper, magnesium matrix hydroxyapatite composite material was prepared by electrophoretic deposition method. The optimal process parameters of electrophoretic deposition were HA suspension concentration of 0.02 kg/L, aging time of 10 days and voltage of 60 V. Animal experiment and SBF immersion experiment were used to test the biocompatibility and bioactivity of this material respectively. The SD rats were divided into control group and implant group. The implant surrounding tissue was taken to do tissue biopsy, HE dyed and organizational analysis after a certain amount of time in the SD rat body. The biological composite material was soaked in SBF solution under homeothermic condition. After 40 days, the bioactivity of the biological composite material was evaluated by testing the growth ability of apatite on composite material. The experiment results showed that magnesium matrix hydroxyapatite biological composite material was successfully prepared by electrophoretic deposition method. Tissue hyperplasia, connective tissue and new blood vessels appeared in the implant surrounding soft tissue. No infiltration of inflammatory cells of lymphocytes and megakaryocytes around the implant was found. After soaked in SBF solution, a layer bone-like apatite was found on the surface of magnesium matrix hydroxyapatite biological composite material. The magnesium matrix hydroxyapatite biological composite material could promot calcium deposition and induce bone-like apatite formation with no cytotoxicity and good biocompatibility and bioactivity.

Network-Based Method for Identifying Co- Regeneration Genes in Bone, Dentin, Nerve and Vessel Tissues.

Science.gov (United States)

Chen, Lei; Pan, Hongying; Zhang, Yu-Hang; Feng, Kaiyan; Kong, XiangYin; Huang, Tao; Cai, Yu-Dong

2017-10-02

Bone and dental diseases are serious public health problems. Most current clinical treatments for these diseases can produce side effects. Regeneration is a promising therapy for bone and dental diseases, yielding natural tissue recovery with few side effects. Because soft tissues inside the bone and dentin are densely populated with nerves and vessels, the study of bone and dentin regeneration should also consider the co-regeneration of nerves and vessels. In this study, a network-based method to identify co-regeneration genes for bone, dentin, nerve and vessel was constructed based on an extensive network of protein-protein interactions. Three procedures were applied in the network-based method. The first procedure, searching, sought the shortest paths connecting regeneration genes of one tissue type with regeneration genes of other tissues, thereby extracting possible co-regeneration genes. The second procedure, testing, employed a permutation test to evaluate whether possible genes were false discoveries; these genes were excluded by the testing procedure. The last procedure, screening, employed two rules, the betweenness ratio rule and interaction score rule, to select the most essential genes. A total of seventeen genes were inferred by the method, which were deemed to contribute to co-regeneration of at least two tissues. All these seventeen genes were extensively discussed to validate the utility of the method.

Lemongrass-Incorporated Tissue Conditioner Against Candida albicans Culture

Science.gov (United States)

Amornvit, Pokpong; Srithavaj, Theerathavaj

2014-01-01

Background: Tissue conditioner is applied popularly with dental prosthesis during wound healing process but it becomes a reservoir of oral microbiota, especially Candida species after long-term usage. Several antifungal drugs have been mixed with this material to control fungal level. In this study, lemongrass essential oil was added into COE-COMFORT tissue conditioner before being determined for anti-Candida efficacy. Materials and Methods: Lemongrass (Cymbopogon citratus) essential oil was primarily determined for antifungal activity against C. albicans American type culture collection (ATCC) 10231 and MIC (minimum inhibitory concentration) value by agar disk diffusion and broth microdilution methods, respectively. COE-COMFORT tissue conditioner was prepared as recommended by the manufacturer after a fixed volume of the oil at its MIC or higher concentrations were mixed thoroughly in its liquid part. Antifungal efficacy of the tissue conditioner with/without herb was finally analyzed. Results: Lemongrass essential oil displayed potent antifungal activity against C. albicans ATCC 10231and its MIC value was 0.06% (v/v). Dissimilarly, the tissue conditioner containing the oil at MIC level did not cease the growth of the tested fungus. Both reference and clinical isolates of C. albicans were completely inhibited after exposed to the tissue conditioner containing at least 0.25% (v/v) of the oil (approximately 4-time MIC). The tissue conditioner without herb or with nystatin was employed as negative or positive control, respectively. Conclusion: COE-COMFORT tissue conditioner supplemented with lemongrass essential oil obviously demonstrated another desirable property as in vitro anti-Candida efficacy to minimize the risk of getting Candidal infection. PMID:25177638

Novel Method of Preparation and Activity Research on Arctigenin from Fructus Arctii.

Science.gov (United States)

Cai, Enbo; Han, Jiahong; Yang, Limin; Zhang, Weiyuan; Zhao, Yan; Chen, Qiulian; Guo, Meng; He, Xinhong

2018-01-01

Arctigenin has many pharmacological activities with clinical significance and is derived from Arctium lappa L. However, the present extraction method is inefficient and does not have meaningful industrial production. A new method to directly prepare arctigenin was established by combining enzyme-assisted extraction and central composite design. Arctigenin's further pharmacological activity was also surveyed in vitro . β-D-Glucosidase, a food-grade enzyme, was added directly to the fruits of A. lappa L. to hydrolyze the arctiin to arctigenin, and the obtained samples were subsequently subjected to ethanol (30%, v/v) extraction. The pharmacological activity of the extraction and arctigenin was determined by inhibiting acetylcholinesterase (AChE) and scavenging nitrite. The factors investigated include the enzyme concentration (0.5%-2.5%), ultrasound time (10 min -3 0 min), and extraction temperature (30°C-50°C). From the analysis of the results by Design-Expert (V8.0.6), the optimal extraction conditions were obtained: enzyme concentration (1.4%), ultrasound time (25 min), and extraction temperature (45°C). The highest yield of arctigenin, obtained under the optimal conditions was 6.39%, representing an increase of 28.15% compared to the reference extraction without enzyme processing. The IC 50 values of the extraction and arctigenin, respectively, for inhibiting AChE were 0.572 mg/ml and 0.462 mg/ml, and those for nitrite-scavenging were 34.571 mg/ml and 17.49 mg/ml. The results demonstrate that using an enzyme directly in the production is an effective means for extracting arctigenin from Fructus arctii. The extraction has the activities of inhibiting AChE and scavenging nitrite, probably because there has arctigenin in it. It is implied that the extraction and arctigenin could contribute to human health in clinical applications. The new method of adding enzyme directly to the preparation of arctigenin was carried out instead of preparing arctigenin by two

Thermal stability of Al-Cu-Fe quasicrystals prepared by SHS method

Directory of Open Access Journals (Sweden)

Pavel Novak

2013-02-01

Full Text Available Quasicrystal-containing materials are usually prepared by rapid solidification of the melt (e.g. by melt spinning or mechanical alloying. In this work, the method using exothermic reactions between compressed metallic powders called SHS (Self-propagating High-temperature Synthesis was tested. The microstructure and phase composition of the product was described in dependence on cooling regime from the reaction temperature. Thermal stability of prepared Al-Cu-Fe quasicrystals was studied by annealing at the temperatures of 300 and 500 °C.

THERMAL STABILITY OF Al-Cu-Fe QUASICRYSTALS PREPARED BY SHS METHOD

Directory of Open Access Journals (Sweden)

Pavel Novák

2013-04-01

Full Text Available Quasicrystal-containing materials are usually prepared by rapid solidification of the melt (e.g. by melt spinning or mechanical alloying. In this work, the method using exothermic reactions between compressed metallic powders called SHS (Self-propagating High-temperature Synthesis was tested. The microstructure and phase composition of the product was described in dependence on cooling regime from the reaction temperature. Thermal stability of prepared Al-Cu-Fe quasicrystals was studied by annealing at the temperatures of 300 and 500 °C.

Decay-time measurements on 'pure' CsI scintillators prepared by different methods

International Nuclear Information System (INIS)

Keszthelyi-Landori, S.; Foeldvari, I.; Voszka, R.; Fodor, Z.; Seres, Z.

1990-05-01

The discovery of the fast decay time of the pure CsI and the various results of the measured samples led to the investigation of decay time of CsI crystals prepared by different methods. Carefully grown or prepared pure CsI behaves as fast scintillators with well or totally suppressed slow decay component. The estimated fast/slow or fast/total ratio is related to the preparation method and to the remaining built-in contamination of the samples. The fast decay of pure CsI consists of two components with decay times of ≅1 and ≅10 ns - with an intensity ratio of 0.3 and 0.65 for gamma and for alpha radiation, respectively. This new ≅1 ns component and the ≅0.8 fast/total ratio may achieve an important role in many applications where fast timing properties are needed, substituting BaF 2 . (author) 18 refs.; 8 figs.; 3 tabs

[Study on two preparation methods for beta-CD inclusion compound of four traditional Chinese medicine volatile oils].

Science.gov (United States)

Li, Hailiang; Cui, Xiaoli; Tong, Yan; Gong, Muxin

2012-04-01

To compare inclusion effects and process conditions of two preparation methods-colloid mill and saturated solution-for beta-CD inclusion compound of four traditional Chinese medicine volatile oils and study the relationship between each process condition and volatile oil physical properties and the regularity of selective inclusion of volatile oil components. Volatile oils from Nardostachyos Radix et Rhizoma, Amomi Fructus, Zingiberis Rhizoma and Angelicaesinensis Radix were prepared using two methods in the orthogonal test. These inclusion compounds by optimized processes were assessed and compared by such methods as TLC, IR and scanning electron microscope. Inclusion oils were extracted by steam distillation, and the components found before and after inclusion were analyzed by GC-MS. Analysis showed that new inclusion compounds, but inclusion compounds prepared by the two processes had differences to some extent. The colloid mill method showed a better inclusion effect than the saturated solution method, indicating that their process conditions had relations with volatile oil physical properties. There were differences in the inclusion selectivity of components between each other. The colloid mill method for inclusion preparation is more suitable for industrial requirements. To prepare volatile oil inclusion compounds with heavy gravity and high refractive index, the colloid mill method needs longer time and more water, while the saturated solution method requires higher temperature and more beta-cyclodextrin. The inclusion complex prepared with the colloid mill method contains extended molecular weight chemical composition, but the kinds of components are reduced.

Effect of mixing method on the mixing degree during the preparation of triturations.

Science.gov (United States)

Nakamura, Hitoshi; Yanagihara, Yoshitsugu; Sekiguchi, Hiroko; Komada, Fusao; Kawabata, Haruno; Ohtani, Michiteru; Saitoh, Yukiya; Kariya, Satoru; Suzuki, Hiroshi; Uchino, Katsuyoshi; Iga, Tatsuji

2004-03-01

By using lactose colored with erythrocin, we investigated the effects of mixing methods on mixing degree during the preparation of trituration with a mortar and pestle. The extent of powder dilution was set to 4 to 64 fold in the experiments. We compared the results obtained by using two methods: (1) one-step mixing of powders after addition of diluents and (2) gradual mixing of powders after addition of diluents. As diluents, we used crystallized lactose and powdered lactose for the preparation of trituration. In the preparation of 64-fold trituration, an excellent degree of mixing was obtained, with CV values of less than 6.08%, for both preparation methods and for the two kinds of diluents. The mixing of two kinds of powders whose distributions of particle sizes were similar resulted in much better degree of mixing, with CV values of less than 3.0%. However, the concentration of principal agents in 64-fold trituration was reduced by 20% due to the adsorption of dye to the apparatus. Under conditions in which a much higher dilution rate and/or much better degree of dilution was required, it must be necessary to dilute powders with considering their physicality and to determine the concentrations of principal agents after the mixing.

Comparison of the suitability of alkaline or enzymatic sample pre-treatment for characterization of silver nanoparticles in human tissue by single particle ICP-MS

DEFF Research Database (Denmark)

Vidmar, Janja; Buerki-Thurnherr, Tina; Löschner, Katrin

2018-01-01

and their size are required for studying NP accumulation in placental tissue. In the present study, we applied and compared two sample preparation techniques, alkaline and enzymatic treatment, followed by single particle ICP-MS (spICP-MS) analysis, for characterizing AgNPs spiked to human placental tissue. Both...... sample preparation approaches are currently used for AgNPs in biological tissues but have not been directly compared yet. We showed that the method using enzymatic tissue treatment followed by spICP-MS is efficient for determination of mass and number concentration and size distribution of AgNPs in human...... placental tissues. Properties of the AgNPs were preserved during enzymatic digestion and comparable with the primary particles. The matrix effect on the determination of Ag sensitivity and transport efficiency in spICP-MS analysis was systematically evaluated as well. The method was applied to human...

Assessing accumulated hard-tissue debris using micro-computed tomography and free software for image processing and analysis.

Science.gov (United States)

De-Deus, Gustavo; Marins, Juliana; Neves, Aline de Almeida; Reis, Claudia; Fidel, Sandra; Versiani, Marco A; Alves, Haimon; Lopes, Ricardo Tadeu; Paciornik, Sidnei

2014-02-01

The accumulation of debris occurs after root canal preparation procedures specifically in fins, isthmus, irregularities, and ramifications. The aim of this study was to present a step-by-step description of a new method used to longitudinally identify, measure, and 3-dimensionally map the accumulation of hard-tissue debris inside the root canal after biomechanical preparation using free software for image processing and analysis. Three mandibular molars presenting the mesial root with a large isthmus width and a type II Vertucci's canal configuration were selected and scanned. The specimens were assigned to 1 of 3 experimental approaches: (1) 5.25% sodium hypochlorite + 17% EDTA, (2) bidistilled water, and (3) no irrigation. After root canal preparation, high-resolution scans of the teeth were accomplished, and free software packages were used to register and quantify the amount of accumulated hard-tissue debris in either canal space or isthmus areas. Canal preparation without irrigation resulted in 34.6% of its volume filled with hard-tissue debris, whereas the use of bidistilled water or NaOCl followed by EDTA showed a reduction in the percentage volume of debris to 16% and 11.3%, respectively. The closer the distance to the isthmus area was the larger the amount of accumulated debris regardless of the irrigating protocol used. Through the present method, it was possible to calculate the volume of hard-tissue debris in the isthmuses and in the root canal space. Free-software packages used for image reconstruction, registering, and analysis have shown to be promising for end-user application. Copyright © 2014. Published by Elsevier Inc.

Improved resolution by mounting of tissue sections for laser microdissection.

Science.gov (United States)

van Dijk, M C R F; Rombout, P D M; Dijkman, H B P M; Ruiter, D J; Bernsen, M R

2003-08-01

Laser microbeam microdissection has greatly facilitated the procurement of specific cell populations from tissue sections. However, the fact that a coverslip is not used means that the morphology of the tissue sections is often poor. To develop a mounting method that greatly improves the morphological quality of tissue sections for laser microbeam microdissection purposes so that the identification of target cells can be facilitated. Fresh frozen tissue and formalin fixed, paraffin wax embedded tissue specimens were used to test the morphological quality of mounted and unmounted tissue. The mounting solution consisted of an adhesive gum and blue ink diluted in water. Interference of the mounting solution with DNA quality was analysed by the polymerase chain reaction using 10-2000 cells isolated by microdissection from mounted and unmounted tissue. The mounting solution greatly improved the morphology of tissue sections for laser microdissection purposes and had no detrimental effects on the isolation and efficiency of amplification of DNA. One disadvantage was that the mounting solution reduced the cutting efficiency of the ultraviolet laser. To minimise this effect, the mounting solution should be diluted as much as possible. Furthermore, the addition of blue ink to the mounting medium restores the cutting efficiency of the laser. The mounting solution is easy to prepare and apply and can be combined with various staining methods without compromising the quality of the DNA extracted.

Investigation of real tissue water equivalent path lengths using an efficient dose extinction method

Science.gov (United States)

Zhang, Rongxiao; Baer, Esther; Jee, Kyung-Wook; Sharp, Gregory C.; Flanz, Jay; Lu, Hsiao-Ming

2017-07-01

For proton therapy, an accurate conversion of CT HU to relative stopping power (RSP) is essential. Validation of the conversion based on real tissue samples is more direct than the current practice solely based on tissue substitutes and can potentially address variations over the population. Based on a novel dose extinction method, we measured water equivalent path lengths (WEPL) on animal tissue samples to evaluate the accuracy of CT HU to RSP conversion and potential variations over a population. A broad proton beam delivered a spread out Bragg peak to the samples sandwiched between a water tank and a 2D ion-chamber detector. WEPLs of the samples were determined from the transmission dose profiles measured as a function of the water level in the tank. Tissue substitute inserts and Lucite blocks with known WEPLs were used to validate the accuracy. A large number of real tissue samples were measured. Variations of WEPL over different batches of tissue samples were also investigated. The measured WEPLs were compared with those computed from CT scans with the Stoichiometric calibration method. WEPLs were determined within  ±0.5% percentage deviation (% std/mean) and  ±0.5% error for most of the tissue surrogate inserts and the calibration blocks. For biological tissue samples, percentage deviations were within  ±0.3%. No considerable difference (extinction measurement took around 5 min to produce ~1000 WEPL values to be compared with calculations. This dose extinction system measures WEPL efficiently and accurately, which allows the validation of CT HU to RSP conversions based on the WEPL measured for a large number of samples and real tissues.

Bioprinting of 3D Tissue Models Using Decellularized Extracellular Matrix Bioink.

Science.gov (United States)

Pati, Falguni; Cho, Dong-Woo

2017-01-01

Bioprinting provides an exciting opportunity to print and pattern all the components that make up a tissue-cells and extracellular matrix (ECM) material-in three dimensions (3D) to generate tissue analogues. A large number of materials have been used for making bioinks; however, majority of them cannot represent the complexity of natural ECM and thus are unable to reconstitute the intrinsic cellular morphologies and functions. We present here a method for making of bioink from decellularized extracellular matrices (dECMs) and a protocol for bioprinting of cell-laden constructs with this novel bioink. The dECM bioink is capable of providing an optimized microenvironment that is conducive to the growth of 3D structured tissue. We have prepared bioinks from different tissues, including adipose, cartilage and heart tissues and achieved high cell viability and functionality of the bioprinted tissue structures using our novel bioink.

Porous electrode preparation method

Science.gov (United States)

Arons, R.M.; Dusek, J.T.

1983-10-18

A porous sintered plaque is provided with a bimodal porosity that is especially well suited for use as an electrode within a molten carbonate fuel cell. The coarse porosity is sufficient for admitting gases into contact with the reaction surfaces while the fine porosity is wetted with and retains molten electrolyte on the reaction sites. The electrode structure is prepared by providing a very fine powder of such as nickel oxide and blending the powder with a suitable decomposable binder to form a solid mass. The mass is comminuted into agglomerate size particles substantially larger than the fine oxide particles and formed into a cohesive compact for subsequent sintering. Sintering is carried out at sufficient conditions to bind the agglomerates together into a porous structure having both coarse and fine porosity. Where lithiated nickel oxide cathodes are prepared, the sintering conditions can be moderate enough to retain substantial quantities of lithium within the electrode for adequate conductivity. 2 figs.

A Rapid Synthetic Method for the Preparation of Two Tris-Cobalt(III) Compounds.

Science.gov (United States)

Jackman, Donald C.; Rillema, D. Paul

1989-01-01

Reports a method of preparation for tris(ethylenediamine)cobalt(III) and tris(2,2'-bipyridine)cobalt(III) that will shorten the preparation time by approximately 3 hours. Notes the time for synthesis and isolation of compound one was 1 hour (yield 38 percent) while compound two took 50 minutes (yield 71%). (MVL)

Method of preparing light-weight plugging mud

Energy Technology Data Exchange (ETDEWEB)

Gorskiy, V F; Melnichuk, A N; Vernikovskiy, A N

1982-01-01

A method is proposed for preparing a light-weight plugging mud which includes mixing Portland cement on an aqueous suspension of palygorskite. It is distinguished by the fact that in order to improve the quality of the mud and strength of the cement stone with simultaneous decrease in the gas permeability, before mixing the Portland cement, the aqueous suspension of palygorskite is dispersed to stabilization of viscosity, and after mixing the Portland cement, the obtained cement-clay mixture is exposed to additional dispersion under pressure. The ratio of the ingredients is the following (% by mass): Portland cement 32.0-61.0; palygorskite 1.2-2.9; water--the rest.

Effect of sample preparation method on quantification of polymorphs using PXRD.

Science.gov (United States)

Alam, Shahnwaz; Patel, Sarsvatkumar; Bansal, Arvind Kumar

2010-01-01

The purpose of this study was to improve the sensitivity and accuracy of quantitative analysis of polymorphic mixtures. Various techniques such as hand grinding and mixing (in mortar and pestle), air jet milling and ball milling for micronization of particle and mixing were used to prepare binary mixtures. Using these techniques, mixtures of form I and form II of clopidogrel bisulphate were prepared in various proportions from 0-5% w/w of form I in form II and subjected to x-ray powder diffraction analysis. In order to obtain good resolution in minimum time, step time and step size were varied to optimize scan rate. Among the six combinations, step size of 0.05 degrees with step time of 5 s demonstrated identification of maximum characteristic peaks of form I in form II. Data obtained from samples prepared using both grinding and mixing in ball mill showed good analytical sensitivity and accuracy compared to other methods. Powder x-ray diffraction method was reproducible, precise with LOD of 0.29% and LOQ of 0.91%. Validation results showed excellent correlation between actual and predicted concentration with R2 > 0.9999.

V-amylose structural characteristics, methods of preparation, significance, and potential applications

CSIR Research Space (South Africa)

Obiro, WC

2012-02-01

Full Text Available , and postprandial hyperglycaemia in diabetics. Various aspects of V-amylose structure, methods of preparation, factors that affect its formation, and the significance and potential applications of the V-amylose complexes are reviewed....

Acoustic Radiation Force-Induced Creep-Recovery (ARFICR): A Noninvasive Method to Characterize Tissue Viscoelasticity.

Science.gov (United States)

Amador Carrascal, Carolina; Chen, Shigao; Urban, Matthew W; Greenleaf, James F

2018-01-01

Ultrasound shear wave elastography is a promising noninvasive, low cost, and clinically viable tool for liver fibrosis staging. Current shear wave imaging technologies on clinical ultrasound scanners ignore shear wave dispersion and use a single group velocity measured over the shear wave bandwidth to estimate tissue elasticity. The center frequency and bandwidth of shear waves induced by acoustic radiation force depend on the ultrasound push beam (push duration, -number, etc.) and the viscoelasticity of the medium, and therefore are different across scanners from different vendors. As a result, scanners from different vendors may give different tissue elasticity measurements within the same patient. Various methods have been proposed to evaluate shear wave dispersion to better estimate tissue viscoelasticity. A rheological model such as the Kelvin-Voigt model is typically fitted to the shear wave dispersion to solve for the elasticity and viscosity of tissue. However, these rheological models impose strong assumptions about frequency dependence of elasticity and viscosity. Here, we propose a new method called Acoustic Radiation Force Induced Creep-Recovery (ARFICR) capable of quantifying rheological model-independent measurements of elasticity and viscosity for more robust tissue health assessment. In ARFICR, the creep-recovery time signal at the focus of the push beam is used to calculate the relative elasticity and viscosity (scaled by an unknown constant) over a wide frequency range. Shear waves generated during the ARFICR measurement are also detected and used to calculate the shear wave velocity at its center frequency, which is then used to calibrate the relative elasticity and viscosity to absolute elasticity and viscosity. In this paper, finite-element method simulations and experiments in tissue mimicking phantoms are used to validate and characterize the extent of viscoelastic quantification of ARFICR. The results suggest that ARFICR can measure tissue

Method of preparing an Al-Ti-B grain refiner for aluminium-comprising products, and a method of casting aluminium products

NARCIS (Netherlands)

Brinkman, H.J.; Duszczyk, J.; Katgerman, L.

1999-01-01

The invention relates to a method of preparing an Al-Ti-B grain refiner for cast aluminium-comprising products. According to the invention the preparation is realized by mixing powders selected from the group comprising aluminium, titanium, boron, and alloys and intermetallic compounds thereof,

Method of preparing highly active and thermostable preparations of liver uridin-kinase usable for enzymic synthesis of radioactive nucleoside-5'-phosphates

International Nuclear Information System (INIS)

Cihak, A.; Vesely, J.

1975-01-01

A method is described of preparing a high-activity uridine kinase for the enzymic synthesis of radioactive nucleoside-5m-phosphates of the pyrimidine series. The preparation is separated from male rat liver after intraperitoneal application of 5'-azacytidine. Examples are given showing detailed procedures for the conversion of uridine and 6-azauridine to the corresponding 5'-phosphates. (L.K.)

Fabrication of silk fibroin film using centrifugal casting technique for corneal tissue engineering.

Science.gov (United States)

Lee, Min Chae; Kim, Dong-Kyu; Lee, Ok Joo; Kim, Jung-Ho; Ju, Hyung Woo; Lee, Jung Min; Moon, Bo Mi; Park, Hyun Jung; Kim, Dong Wook; Kim, Su Hyeon; Park, Chan Hum

2016-04-01

Films prepared from silk fibroin have shown potential as biomaterials in tissue engineering applications for the eye. Here, we present a novel process for fabrication of silk fibroin films for corneal application. In this work, fabrication of silk fibroin films was simply achieved by centrifugal force. In contrast to the conventional dry casting method, we carried out the new process in a centrifuge with a rotating speed of 4000 rpm, where centrifugal force was imposed on an aluminum tube containing silk fibroin solution. In the present study, we also compared the surface roughness, mechanical properties, transparency, and cell proliferation between centrifugal and dry casting method. In terms of surface morphology, films fabricated by the centrifugal casting have less surface roughness than those by the dry casting. For elasticity and transparency, silk fibroin films obtained from the centrifugal casting had favorable results compared with those prepared by dry casting. Furthermore, primary human corneal keratocytes grew better in films prepared by the centrifugal casting. Therefore, our results suggest that this new fabrication process for silk fibroin films offers important potential benefits for corneal tissue regeneration. © 2015 Wiley Periodicals, Inc.

Determination of piroxicam from rat articular tissue and plasma based on LC-MS/MS.

Science.gov (United States)

Kim, Han Sol; Cho, Ha Ra; Ho, Myoung Jin; Kang, Myung Joo; Choi, Yong Seok

2016-12-01

Osteoarthritis (OA) is the most common type of arthritis. To manage OA, in general, oral administration of non-steroidal anti-inflammatory drugs (NSAIDs) is used. Recently, the analgesic and anti-inflammatory efficacy of piroxicam (PX), a long-acting NSAID, by intra-articular (IA) administration in OA was reported, and the possibility that PX is distributed in articular tissues at a certain concentration was raised. Thus, herein, novel LC-MS/MS methods to detect PX in rat articular tissue and plasma are presented. For articular tissue, solvent extraction with acetonitrile for 12 h was employed and a protein precipitation method was used for the preparation of a plasma sample. The developed methods were validated by following the FDA guidelines, and the validated methods were successfully applied to a PK study of IA PX. The present study presents, to our knowledge, the first method of determining a drug in articular tissue. Additionally, the level of PX in articular tissue after IA PX administration was experimentally confirmed for the first time using the present methods. Therefore, the present methods provide a new direction for in vivo evaluation for IA PX formulations and contribute to the development of alternative IA PX formulations with better effects for the treatment of OA.

Traditional and New methods for the Preparation of Diazocarbonyl Compounds

Directory of Open Access Journals (Sweden)

ANTONIO C.B. BURTOLOSO

2018-04-01

Full Text Available ABSTRACT For many years diazocarbonyl compounds have been studied due to their versatility and usability in many chemical transformations. In this review, we summarize the traditional methods to prepare these compounds as well as the new methods and recent improvements in experimental procedures. Moreover, emergence of continuous flow techniques has allowed safer and environmentally friendly procedures for the handling of diazomethane and diazo compounds and will also be a topic in this review.

Development of a 117mSn preparation method

International Nuclear Information System (INIS)

Moraes, Vanessa; Osso Junior, Joao Alberto

2000-01-01

117m Sn is a radioisotope with suitable characteristics to be used in nuclear medicine as radiotherapy, when labeled with DTPA. The aim of this work is the preparation of 117m Sn from irradiation of the natural tin with proton beam at the cyclotron CV-28 of IPEN-CNEN/SP via the nuclear reaction nat Sn (p, xn) 117 Sb to 117m Sn. Due to the formation of the Sb precursor it is necessary to perform a chemical separation for Sb-Sn. The separation method used was the ion exchange, due to its utilization facilities for radioactive material. Chemical, radiochemical and radionuclidic methods were also developed for the quality control of the final product, the 117m Sn. (author)

Preparation of antimony-doped nanoparticles by hydrothermal method

Institute of Scientific and Technical Information of China (English)

JIANG Ming-xi; YANG Tian-zu; GU Ying-ying; DU Zuo-juan; LIU Jian-ling

2005-01-01

Antimony-doped tin oxide(ATO) nanoparticles were prepared by the mild hydrothermal method at 200 ℃ using sodium stannate, antimony oxide, sodium hydroxide and sulfuric acid as the starting materials. The doped powders were examined by differential thermal analysis(DTA), X-ray diffractometry(XRD) and transmission electron microscopy(TEM). The doping levels of antimony were determined by volumetric method and iodimetry.The results show that antimony is incorporated into the crystal lattice of tin oxide and the doping levels of antimony in the resulting powders are 2.4%, 4.3 % and 5.1 % (molar fraction). The mean particle size of ATO nanoparticles is in the range of 25 - 30 nm. The effects of antimony doping level on the crystalline size and crystallinity were also discussed.

Studies on the complexation of diclofenac sodium with β-cyclodextrin: Influence of method of preparation

Science.gov (United States)

Das, Subhraseema; Subuddhi, Usharani

2015-11-01

Inclusion complexes of diclofenac sodium (DS) with β-cyclodextrin (β-CD) were prepared in order to improve the solubility, dissolution and oral bioavailability of the poorly water soluble drug. The effect of method of preparation of the DS/β-CD inclusion complexes (ICs) was investigated. The ICs were prepared by microwave irradiation and also by the conventional methods of kneading, co-precipitation and freeze drying. Though freeze drying method is usually referred to as the gold standard among all the conventional methods, its long processing time limits the utility. Microwave irradiation accomplishes the process in a very short span of time and is a more environmentally benign method. Better efficacy of the microwaved inclusion product (MW) was observed in terms of dissolution, antimicrobial activity and antibiofilm properties of the drug. Thus microwave irradiation can be utilized as an improved, time-saving and cost-effective method for the generation of DS/β-CD inclusion complexes.

Transmission Electron Microscopy Specimen Preparation Method for Multiphase Porous Functional Ceramics

DEFF Research Database (Denmark)

Zhang, Wei; Kuhn, Luise Theil; Jørgensen, Peter Stanley

2013-01-01

An optimum method is proposed to prepare thin foil transmission electron microscopy (TEM) lamellae of multiphase porous functional ceramics: prefilling the pore space of these materials with an epoxy resin prior to focused ion beam milling. Several advantages of epoxy impregnation are demonstrated...... by successful preparation of TEM specimens that maintain the structural integrity of the entire lamella. Feasibility of the TEM alignment procedure is demonstrated, and ideal TEM analyses are illustrated on solid oxide fuel cell and solid oxide electrolysis cell materials. Some potential drawbacks of the TEM...

Development of a method for controlling salt and sodium use during meal preparation for food services

Directory of Open Access Journals (Sweden)

Cristina Barbosa Frantz

2013-02-01

Full Text Available OBJECTIVE: The study developed a method for controlling the amount of salt and sodium during food preparation, Controlling Salt and Sodium use During Meal Preparation for food services based on the Hazard Analysis and Critical Control Points principles. METHODS: The method was conceived and perfected during a study case in a commercial food service located in Florianópolis, Santa Catarina, Brazil. Data were collected from technical cards, recipes and measurements during food preparation. The preparations were monitored and compared with criteria about the use of salt and sodium found in the literature. Critical control points were identified and corrective measures were proposed. RESULTS: The result was a method consisting of 9 stages: (1 determination of the sodium content in the ingredients; (2 and 3 analysis of menu planning and sodium content; (4 follow-up of food preparation; (5 estimate of the amount of sodium used in the preparations; (6 and 7 selection and following of the preparations with average- and high-sodium content; (8 definition of the critical points and establishment of corrective actions for the use of salt and sodium; and (9 creation of recommendations for the use of salt and sodium. CONCLUSION: The Controlling Salt and Sodium use During Meal Preparation may contribute to global discussions regarding the reduction of salt and sodium intakes and collaborate for the supply of nutritionally and sensorially appropriate meals with respect to salt and sodium content. It may also help to prevent non-communicable chronic diseases.

Technetium-99m labeled radiodiagnostic agents and method of preparation

International Nuclear Information System (INIS)

1976-01-01

A method of preparing improved technetium-99m labelled radiodiagnostic agents by reducing sup(99m)Tc-pertechnetate with stannous tartrate is given. Human serum albumine (HSA) and 1-hydroxyethylidene-1,1-disodiumphosphonate (HEDSPA), which are useful in scintigraphic examinations of the lung and bone, were labelled in this way

Preparation of oxide glasses from metal alkoxides by sol-gel method

Science.gov (United States)

Kamiya, K.; Yoko, T.; Sakka, S.

1987-01-01

An investigation is carried out on the types of siloxane polymers produced in the course of the hydrolysis of silicon tetraethoxide, as well as the preparation of oxide glasses from metal alkoxides by the sol-gel method.

Preparation and comparative characterization of keratin–chitosan and keratin–gelatin composite scaffolds for tissue engineering applications

International Nuclear Information System (INIS)

Balaji, S.; Kumar, Ramadhar; Sripriya, R.; Kakkar, Prachi; Ramesh, D. Vijaya; Reddy, P. Neela Kanta; Sehgal, P.K.

2012-01-01

We report fabrication of three dimensional scaffolds with well interconnected matrix of high porosity using keratin, chitosan and gelatin for tissue engineering and other biomedical applications. Scaffolds were fabricated using porous Keratin–Gelatin (KG), Keratin–Chitosan (KC) composites. The morphology of both KG and KC was investigated using SEM. The scaffolds showed high porosity with interconnected pores in the range of 20–100 μm. They were further tested by FTIR, DSC, CD, tensile strength measurement, water uptake and swelling behavior. In vitro cell adhesion and cell proliferation tests were carried out to study the biocompatibility behavior and their application as an artificial skin substitute. Both KG and KC composite scaffolds showed similar properties and patterns for cell proliferation. Due to rapid degradation of gelatin in KG, we found that it has limited application as compared to KC scaffold. We conclude that KC scaffold owing to its slow degradation and antibacterial properties would be a better substrate for tissue engineering and other biomedical application. Highlights: ► Extraction of reduced keratin from horn meal. ► Preparation of keratin–gelatin and keratin–chitosan composite scaffolds. ► Characterizations of the composite scaffolds. ► Comparative cytotoxicity analysis on NIH3T3 fibroblasts.

Spinal Tissue Loading Created by Different Methods of Spinal Manipulative Therapy Application.

Science.gov (United States)

Funabashi, Martha; Nougarou, François; Descarreaux, Martin; Prasad, Narasimha; Kawchuk, Gregory N

2017-05-01

Comparative study using robotic replication of spinal manipulative therapy (SMT) vertebral kinematics together with serial dissection. The aim of this study was to quantify loads created in cadaveric spinal tissues arising from three different forms of SMT application. There exist many distinct methods by which to apply SMT. It is not known presently whether different forms of SMT application have different effects on spinal tissues. Should the method of SMT application modulate spinal tissue loading, quantifying this relation may help explain the varied outcomes of SMT in terms of effect and safety. SMT was applied to the third lumbar vertebra in 12 porcine cadavers using three SMT techniques: a clinical device that applies forces through a hand-held instrument (INST), a manual technique of applying SMT clinically (MAN) and a research device that applies parameters of manual SMT through a servo-controlled linear actuator motor (SERVO). The resulting kinematics from each SMT application were tracked optically via indwelling bone pins. The L3/L4 segment was then removed, mounted in a parallel robot and the resulting kinematics from SMT replayed for each SMT application technique. Serial dissection of spinal structures was conducted to quantify loading characteristics of discrete spinal tissues. In terms of load magnitude, SMT application with MAN and SERVO created greater forces than INST in all conditions (P < 0.05). Additionally, MAN and SERVO created comparable posterior forces in the intact specimen, but MAN created greater posterior forces on IVD structures compared to SERVO (P < 0.05). Specific methods of SMT application create unique vertebral loading characteristics, which may help explain the varied outcomes of SMT in terms of effect and safety. N/A.

An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

Energy Technology Data Exchange (ETDEWEB)

Chisvert, Alberto, E-mail: alberto.chisvert@uv.es [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Leon-Gonzalez, Zacarias [Unidad Analitica, Instituto de Investigacion Sanitaria Fundacion Hospital La Fe, 46009 Valencia (Spain); Tarazona, Isuha; Salvador, Amparo [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Giokas, Dimosthenis [Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

2012-11-08

Highlights: Black-Right-Pointing-Pointer Papers describing the determination of UV filters in fluids and tissues are reviewed. Black-Right-Pointing-Pointer Matrix complexity and low amounts of analytes require effective sample treatments. Black-Right-Pointing-Pointer The published papers do not cover the study of all the substances allowed as UV filters. Black-Right-Pointing-Pointer New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of

An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

International Nuclear Information System (INIS)

Chisvert, Alberto; León-González, Zacarías; Tarazona, Isuha; Salvador, Amparo; Giokas, Dimosthenis

2012-01-01

Highlights: ► Papers describing the determination of UV filters in fluids and tissues are reviewed. ► Matrix complexity and low amounts of analytes require effective sample treatments. ► The published papers do not cover the study of all the substances allowed as UV filters. ► New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of the biological matrix and the low concentration levels of these compounds inevitably impose sample

Complex heterogeneous tissue constructs containing multiple cell types prepared by inkjet printing technology.

Science.gov (United States)

Xu, Tao; Zhao, Weixin; Zhu, Jian-Ming; Albanna, Mohammad Z; Yoo, James J; Atala, Anthony

2013-01-01

This study was designed to develop a versatile method for fabricating complex and heterogeneous three-dimensional (3D) tissue constructs using simultaneous ink-jetting of multiple cell types. Human amniotic fluid-derived stem cells (hAFSCs), canine smooth muscle cells (dSMCs), and bovine aortic endothelial cells (bECs), were separately mixed with ionic cross-linker calcium chloride (CaCl(2)), loaded into separate ink cartridges and printed using a modified thermal inkjet printer. The three cell types were delivered layer-by-layer to pre-determined locations in a sodium alginate-collagen composite located in a chamber under the printer. The reaction between CaCl(2) and sodium alginate resulted in a rapid formation of a solid composite gel and the printed cells were anchored in designated areas within the gel. The printing process was repeated for several cycles leading to a complex 3D multi-cell hybrid construct. The biological functions of the 3D printed constructs were evaluated in vitro and in vivo. Each of the printed cell types maintained their viability and normal proliferation rates, phenotypic expression, and physiological functions within the heterogeneous constructs. The bioprinted constructs were able to survive and mature into functional tissues with adequate vascularization in vivo. These findings demonstrate the feasibility of fabricating complex heterogeneous tissue constructs containing multiple cell types using inkjet printing technology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preparation of pre-cut corneas from fresh donated whole globes for Descemet's stripping automated keratoplasty: 3-year results at the Central Eye Bank of Iran.

Science.gov (United States)

Kanavi, Mozhgan Rezaei; Javadi, Mohammad Ali; Javadi, Fatemeh; Chamani, Tahereh

2014-09-01

To describe the technique and the results of the preparation of pre-cut corneas for Descemet's stripping automated endothelial keratoplasty (DSAEK) during a 3-year period at the Central Eye Bank of Iran (CEBI). The method of preparation of pre-cut corneas from donated whole globes at the CEBI is described and the frequency and percentage of pre-cut corneas prepared for DSAEK, between April 2009 and March 2012, are specified. Moreover, post-operative reports are reviewed for any complaints about using pre-cut tissues for DSAEK. Out of the 1,518 donated whole globes appropriate for DSAEK, 1,478 (97.4 %) pre-cut corneas were successfully prepared. The method of preparation failed in 40 (2.6 %) cases. Based on the eye bank post-operative reports, thickness of pre-cut tissues for DSAEK was deemed unacceptable in only 6 (0.4 %) cases prior to surgery; five of these were too thick and one was too thin. Preparation of pre-cut corneas, for DSAEK from donated whole globes, in the CEBI is a safe and easy method, with very good preservation of endothelial cells after the preparation of the pre-cut corneas and reduced risks from corneal manipulation.

An electrodeposition method for the preparation of actinides and Ra samples for α spectrometry

International Nuclear Information System (INIS)

Garcia-Tenorio, R.; Garcia-Leon, M.; Madurga, G.; Piazza, C.

1986-01-01

As it is confirmed in this work, electrodeposition of α radionuclides gives a simple method for preparing α samples of high spectrometric quality, compared to those prepared by evaporation. Then we give the methods for electrodepositon or α emitters use in our Department. Actinides α emitters are electroplated from a 1% H 2 SO 4 medium with a recovery of about 90%. The samples of Ra are prepared by electrodeposition from a HCl + CH 3 -COONH 4 medium at pH approx.= 5. In this case the recovery reaches a value that ranges from 70 to 90%. For these measurements a Si surface barrier detector has been used. Some of its features are discussed in the text. (author)

Reaction kinetics for preparation of silica film with Stoeber method

International Nuclear Information System (INIS)

Shang Mengying; Jiang Xiaodong; Liu Miao; Luo Xuan; Tang Yongjian; Cao Linhong

2013-01-01

A new formula was proposed to investigate the relationship between reaction time and tetraethylorthosilicate (TEOS) conversion rate for preparation of silica sol with Stöber method, by studying the reaction kinetics of TEOS hydrolytic process. An appropriate conversion rate was then determined and used to calculate the theoretical optimal reaction time. Meanwhile, silica sols were prepared by sol-gel process using TEOS as precursor and ammonia as catalyst. It was found that the reaction time decreases with an increasing amount of ammonia and water. The values of experimental optimal reaction time were obtained, and agree with the theoretical results (the errors are within 5%), which shows good applicability of our formula. (authors)

Hydroxyapatite coatings on titanium dioxide thin films prepared by pulsed laser deposition method

International Nuclear Information System (INIS)

Suda, Yoshiaki; Kawasaki, Hiroharu; Ohshima, Tamiko; Nakashima, Shouta; Kawazoe, Syuichi; Toma, Tetsuya

2006-01-01

Hydroxyapatite (HAp) coated on titanium dioxide (TiO 2 ) thin films has been developed to supplement the defects of both TiO 2 and HAp. Thin films have been prepared by pulsed laser deposition (PLD) method using HAp and HAp(10%) + TiO 2 targets. X-ray diffraction (XRD) shows that there are many small peaks of Ca 1 0(PO 4 ) 6 (OH) 2 crystal, and no impurity other than HAp is detected in HAp films prepared using pure HAp target. The composition ratio of the film was analyzed by X-ray photoelectron spectroscopy (XPS). HAp coatings on TiO 2 thin films have been prepared using HAp(10%) + TiO 2 targets. XRD and XPS measurements suggest that crystalline HAp + TiO 2 thin films are obtained by the PLD method using HAp(10%) + TiO 2 target

[Preparation of panax notoginseng saponins-tanshinone H(A) composite method for pulmonary delivery with spray-drying method and its characterization].

Science.gov (United States)

Wang, Hua-Mei; Fu, Ting-Ming; Guo, Li-Wei

2013-02-01

To prepare panax notoginseng saponins-tanshinone II(A) composite particles for pulmonary delivery, in order to explore a dry powder particle preparation method ensuring synchronized arrival of multiple components of traditional Chinese medicine compounds at absorption sites. Panax notoginseng saponins-tanshinone II(A) composite particles were prepared with spray-drying method, and characterized by scanning electron microscopy (SEM), confocal laser scanning microscope (CLSM), X-ray diffraction (XRD), infrared analysis (IR), dry laser particle size analysis, high performance liquid chromatography (HPLC) and the aerodynamic behavior was evaluated by a Next Generation Impactor (NGI). The dry powder particles produced had narrow particle size distribution range and good aerodynamic behavior, and could realize synchronized administration of multiple components. The spray-drying method is used to combine traditional Chinese medicine components with different physical and chemical properties in the same particle, and product into traditional Chinese medicine compound particles in line with the requirements for pulmonary delivery.

Effect of method of sample preparation on ruminal in situ ...

African Journals Online (AJOL)

Midmar) was harvested at three and four weeks after cutting and fertilizing with 200 kg nitrogen (N)/ha. Freshly cut herbage was used to investigate the following four sample preparation methods. In trial 1, herbage was (1) chopped with a paper-cutting guillotine into 5-10 mm lengths, representing fresh (FR) herbage; ...

Novel silk fibroin films prepared by formic acid/hydroxyapatite dissolution method

International Nuclear Information System (INIS)

Ming, Jinfa; Liu, Zhi; Bie, Shiyu; Zhang, Feng; Zuo, Baoqi

2014-01-01

Bombyx mori silk fibroin from the silkworm was firstly found to be soluble in formic acid/hydroxyapatite system. The rheological behavior of silk fibroin solution was significantly influenced by HAp contents in dissolved solution. At the same time, silk fibroin nanofibers were observed in dissolved solution with 103.6 ± 20.4 nm in diameter. Moreover, the structure behavior of SF films prepared by formic acid/hydroxyapatite dissolution method was examined. The secondary structure of silk fibroin films was attributed to silk II structure (β-sheet), indicating that the hydroxyapatite contents in dissolved solution were not significantly affected by the structure of silk fibroin. The X-ray diffraction results exhibited obviously hydroxyapatite crystalline nature existing in silk fibroin films; however, when the hydroxyapatite content was 5.0 wt.% in dissolved solution, some hydroxyapatite crystals were converted to calcium hydrogen phosphate dehydrate in silk fibroin dissolution process. This result was also confirmed by Fourier transform infrared analysis and DSC measurement. In addition, silk fibroin films prepared by this dissolution method had higher breaking strength and extension at break. Based on these analyses, an understanding of novel SF dissolution method may provide an additional tool for designing and synthesizing advanced materials with more complex structures, which should be helpful in different fields, including biomaterial applications. - Highlights: • SF fibers were firstly successfully dissolved in FA/HAp solution. • The rheological behavior of SF solution was significantly influenced by HAp contents. • SF nanofibrils were observed in FA/HAp solution with 103.6 ± 20.4 nm in diameter. • SF films prepared by FA/HAp dissolution method had higher mechanical properties

Novel silk fibroin films prepared by formic acid/hydroxyapatite dissolution method

Energy Technology Data Exchange (ETDEWEB)

Ming, Jinfa, E-mail: jinfa.ming@gmail.com [National Engineering Laboratory for Modern Silk, Soochow University, Suzhou 215123 (China); College of Textile and Clothing Engineering, Soochow University, Suzhou 215021 (China); Liu, Zhi; Bie, Shiyu [National Engineering Laboratory for Modern Silk, Soochow University, Suzhou 215123 (China); College of Textile and Clothing Engineering, Soochow University, Suzhou 215021 (China); Zhang, Feng [Jiangsu Province Key Laboratory of Stem Cell Research, Medical College, Soochow University, Suzhou 215006 (China); Zuo, Baoqi, E-mail: bqzuo@suda.edu.cn [National Engineering Laboratory for Modern Silk, Soochow University, Suzhou 215123 (China); College of Textile and Clothing Engineering, Soochow University, Suzhou 215021 (China)

2014-04-01

Bombyx mori silk fibroin from the silkworm was firstly found to be soluble in formic acid/hydroxyapatite system. The rheological behavior of silk fibroin solution was significantly influenced by HAp contents in dissolved solution. At the same time, silk fibroin nanofibers were observed in dissolved solution with 103.6 ± 20.4 nm in diameter. Moreover, the structure behavior of SF films prepared by formic acid/hydroxyapatite dissolution method was examined. The secondary structure of silk fibroin films was attributed to silk II structure (β-sheet), indicating that the hydroxyapatite contents in dissolved solution were not significantly affected by the structure of silk fibroin. The X-ray diffraction results exhibited obviously hydroxyapatite crystalline nature existing in silk fibroin films; however, when the hydroxyapatite content was 5.0 wt.% in dissolved solution, some hydroxyapatite crystals were converted to calcium hydrogen phosphate dehydrate in silk fibroin dissolution process. This result was also confirmed by Fourier transform infrared analysis and DSC measurement. In addition, silk fibroin films prepared by this dissolution method had higher breaking strength and extension at break. Based on these analyses, an understanding of novel SF dissolution method may provide an additional tool for designing and synthesizing advanced materials with more complex structures, which should be helpful in different fields, including biomaterial applications. - Highlights: • SF fibers were firstly successfully dissolved in FA/HAp solution. • The rheological behavior of SF solution was significantly influenced by HAp contents. • SF nanofibrils were observed in FA/HAp solution with 103.6 ± 20.4 nm in diameter. • SF films prepared by FA/HAp dissolution method had higher mechanical properties.

Assessment of deep tissue hyperalgesia in the groin – a method comparison of electrical vs. pressure stimulation

DEFF Research Database (Denmark)

Aasvang, E K; Werner, M U; Kehlet, H

2014-01-01

BACKGROUND: Deep pain complaints are more frequent than cutaneous in post-surgical patients, and a prevalent finding in quantitative sensory testing studies. However, the preferred assessment method - pressure algometry - is indirect and tissue unspecific, hindering advances in treatment and prev......BACKGROUND: Deep pain complaints are more frequent than cutaneous in post-surgical patients, and a prevalent finding in quantitative sensory testing studies. However, the preferred assessment method - pressure algometry - is indirect and tissue unspecific, hindering advances in treatment...... thresholds to pressure algometry, by performing identical test-retest sequences 10 days apart, in deep tissues in the groin region. Electrical stimulation was performed by five up-and-down staircase series of single impulses of 0.04 ms duration, starting from 0 mA in increments of 0.2 mA until a threshold......: The presented tissue-specific direct deep tissue electrical stimulation technique has equal or superior reliability compared with the indirect tissue-unspecific stimulation by pressure algometry. This method may facilitate advances in mechanism based preventive and treatment strategies in acute and chronic post...

Preparation and characterization of bismuth ruthenate pyrochlore via solid state reaction and sol-gel methods

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Mayuree Sansernnivet

2010-01-01

Full Text Available Bismuth ruthenate pyrochlores, potential cathode materials for intermediate temperature solid oxide fuel cells(ITSOFCs, were prepared via solid-state and sol-gel method. Effects of the preparation routes and conditions on the phase and microstructures of the materials were investigated in this study using XRD and SEM. The study showed that the preparation method and the adding sequence of the starting meterials have a significant effect on the crystal phase and the particle size obtained. Sol-gel synthesis could yield a material with only pyrochlore structure, i.e. Bi2Ru2O7, while the solid state method yielded powder with a small amount of the secondary RuO2 phase. The sol-gel synthesis resulted in materialswith a finer particle size (~0.3-1.0 μm compared to powder synthesized via the solid state reaction method.

Properties of natural rubber/attapulgite composites prepared by latex compounding method: Effect of filler loading

International Nuclear Information System (INIS)

Muttalib, Siti Nadzirah Abdul; Othman, Nadras; Ismail, Hanafi

2015-01-01

This paper reports on the effect of filler loading on properties of natural rubber (NR)/attapulgite (ATP) composites. The NR/ATP composites were prepared by latex compounding method. It is called as masterbatch. The masterbatch was subsequently added to the NR through melt mixing process. The vulcanized NR/ATP composites were subjected to mechanical, swelling and morphological tests. All the results were compared with NR/ATP composites prepared by conventional system. The composites from masterbatch method showed better results compared to composites prepared by conventional method. They have higher tensile properties, elongation at break and tear strength. The images captured through scanning electron microscopy test revealed the improvement of tensile strength in masterbatch NR/ATP composites. It can be seen clearly that masterbatch NR/ATP have better filler dispersion compared to conventional method NR/ATP composites

Properties of natural rubber/attapulgite composites prepared by latex compounding method: Effect of filler loading

Energy Technology Data Exchange (ETDEWEB)

Muttalib, Siti Nadzirah Abdul, E-mail: sitinadzirah.amn@gmail.com; Othman, Nadras, E-mail: srnadras@usm.my; Ismail, Hanafi, E-mail: ihanafi@usm.my [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

2015-07-22

This paper reports on the effect of filler loading on properties of natural rubber (NR)/attapulgite (ATP) composites. The NR/ATP composites were prepared by latex compounding method. It is called as masterbatch. The masterbatch was subsequently added to the NR through melt mixing process. The vulcanized NR/ATP composites were subjected to mechanical, swelling and morphological tests. All the results were compared with NR/ATP composites prepared by conventional system. The composites from masterbatch method showed better results compared to composites prepared by conventional method. They have higher tensile properties, elongation at break and tear strength. The images captured through scanning electron microscopy test revealed the improvement of tensile strength in masterbatch NR/ATP composites. It can be seen clearly that masterbatch NR/ATP have better filler dispersion compared to conventional method NR/ATP composites.

Comparison between thaw-mounting and use of conductive tape for sample preparation in ToF-SIMS imaging of lipids in Drosophila microRNA-14 model.

Science.gov (United States)

Le, Minh Uyen Thi; Son, Jin Gyeong; Shon, Hyun Kyoung; Park, Jeong Hyang; Lee, Sung Bae; Lee, Tae Geol

2018-03-30

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging elucidates molecular distributions in tissue sections, providing useful information about the metabolic pathways linked to diseases. However, delocalization of the analytes and inadequate tissue adherence during sample preparation are among some of the unfortunate phenomena associated with this technique due to their role in the reduction of the quality, reliability, and spatial resolution of the ToF-SIMS images. For these reasons, ToF-SIMS imaging requires a more rigorous sample preparation method in order to preserve the natural state of the tissues. The traditional thaw-mounting method is particularly vulnerable to altered distributions of the analytes due to thermal effects, as well as to tissue shrinkage. In the present study, the authors made comparisons of different tissue mounting methods, including the thaw-mounting method. The authors used conductive tape as the tissue-mounting material on the substrate because it does not require heat from the finger for the tissue section to adhere to the substrate and can reduce charge accumulation during data acquisition. With the conductive-tape sampling method, they were able to acquire reproducible tissue sections and high-quality images without redistribution of the molecules. Also, the authors were successful in preserving the natural states and chemical distributions of the different components of fat metabolites such as diacylglycerol and fatty acids by using the tape-supported sampling in microRNA-14 (miR-14) deleted Drosophila models. The method highlighted here shows an improvement in the accuracy of mass spectrometric imaging of tissue samples.

Method of preparing an Al-Ti-B grain refiner for aluminium-comprising products, and a method of casting aluminium products

OpenAIRE

Brinkman, H.J.; Duszczyk, J.; Katgerman, L.

1999-01-01

The invention relates to a method of preparing an Al-Ti-B grain refiner for cast aluminium-comprising products. According to the invention the preparation is realized by mixing powders selected from the group comprising aluminium, titanium, boron, and alloys and intermetallic compounds thereof, compressing, heating in an inert environment until an exothermic reaction is initiated and cooling. It has been shown that when the grain refiner thus prepared is applied, the quality of cast products ...

Validation of uncertainty of weighing in the preparation of radionuclide standards by Monte Carlo Method

International Nuclear Information System (INIS)

Cacais, F.L.; Delgado, J.U.; Loayza, V.M.

2016-01-01

In preparing solutions for the production of radionuclide metrology standards is necessary measuring the quantity Activity by mass. The gravimetric method by elimination is applied to perform weighing with smaller uncertainties. At this work is carried out the validation, by the Monte Carlo method, of the uncertainty calculation approach implemented by Lourenco and Bobin according to ISO GUM for the method by elimination. The results obtained by both uncertainty calculation methods were consistent indicating that were fulfilled the conditions for the application of ISO GUM in the preparation of radioactive standards. (author)

Composite Materials with Magnetically Aligned Carbon Nanoparticles and Methods of Preparation

Science.gov (United States)

Hong, Haiping (Inventor); Peterson, G.P. (Bud) (Inventor); Salem, David R. (Inventor)

2018-01-01

The present invention relates to magnetically aligned carbon nanoparticle composites and methods of preparing the same. The composites comprise carbon nanoparticles, host material, magnetically sensitive nanoparticles and surfactant. The composites may have enhanced mechanical, thermal, and/or electrical properties.

Effects of an Er, Cr:YSGG laser on canine oral hard tissues

Science.gov (United States)

Rizoiu, Ioana-Mihaela; Kimmel, Andrew I.; Eversole, Lewis R.

1996-12-01

Beagle dogs were utilized to assess the biologic effects of an Er, Cr:YSGG hard tissue cutting laser and results were compared with conventional mechanical preparations of enamel and dentin. Intraoperative pulpal temperature fluctuations were recorded with thermocouples. The laser cuts failed to induce inflammation in the pulps except in teeth with intentional pulp exposures for both methods. No increase in temperature was detected with the laser. It is concluded that this laser system may be safely employed for tooth preparations without causing adverse pulpal effects.

Preparation and Observation of Fresh-frozen Sections of the Green Fluorescent Protein Transgenic Mouse Head

International Nuclear Information System (INIS)

Tada, Masahito; Shinohara, Yoshinori; Kato, Ichiro; Hiraga, Koichi; Aizawa, Tomoyasu; Demura, Makoto; Mori, Yoshihiro; Shinoda, Hiroyuki; Mizuguchi, Mineyuki; Kawano, Keiichi

2006-01-01

Hard tissue decalcification can cause variation in the constituent protein characteristics. This paper describes a method of preparating of frozen mouse head sections so as to clearly observe the nature of the constituent proteins. Frozen sections of various green fluorescent protein (GFP) transgenic mouse heads were prepared using the film method developed by Kawamoto and Shimizu. This method made specimen dissection without decalcification possible, wherein GFP was clearly observed in an undamaged state. Conversely, using the same method with decalcification made GFP observation in the transgenic mouse head difficult. This new method is suitable for observing GFP marked cells, enabling us to follow the transplanted GFP marked cells within frozen head sections

Spectroscopic techniques in the study of human tissues and their components. Part I: IR spectroscopy.

Science.gov (United States)

Olsztyńska-Janus, Sylwia; Szymborska-Małek, Katarzyna; Gąsior-Głogowska, Marlena; Walski, Tomasz; Komorowska, Małgorzata; Witkiewicz, Wojciech; Pezowicz, Celina; Kobielarz, Magdalena; Szotek, Sylwia

2012-01-01

Among the currently used methods of monitoring human tissues and their components many types of research are distinguished. These include spectroscopic techniques. The advantage of these techniques is the small amount of sample required, the rapid process of recording the spectra, and most importantly in the case of biological samples - preparation of tissues is not required. In this work, vibrational spectroscopy: ATR-FTIR and Raman spectroscopy will be used. Studies are carried out on tissues: tendons, blood vessels, skin, red blood cells and biological components: amino acids, proteins, DNA, plasma, and deposits.

Fast method for the detection of transport process in plant tissues by radiotracing

International Nuclear Information System (INIS)

Antal, K.; Joo, P.

1995-01-01

The efficiency of nutrients, microelements and plant protective agents and additives applied on foliar and various aeriel parts of plants depends on the adsorption of their spray drops and the penetration of agents into tissues, cells and inner caves. The permeability of the cuticular membrane and the mode of entry of above substances through the cuticle and their mobility in other tissues are poorly understood but have been the subject of intensive research. The traditional methods in biological systems are the automicroradiography and sample taking methods. The radioactive tracer method developed by us is suitable for determining the effective diffusion coefficients characterizing the migration process and concentration distributions off these materials in plants by consumption of minimal amount of β-labelled radioactive isotopes in very short time. (author) 9 refs.; 3 figs

Radioprotective effects of a preparation (HemoHIM) of herb mixture on self-renewal tissues and immune system in mice

Energy Technology Data Exchange (ETDEWEB)

Jo, Sung Kee; Park, Hae Ran; Jung, Uhee; Oh, Heon [KAERI, Taejon (Korea, Republic of); Kim, Sung Ho [Chonnam National Univ. Seoul (Korea, Republic of); Yee, Sung Tae [Sunchon National Univ., Seoul (Korea, Republic of)

2004-07-01

A preparation (HemoHIM) of herb mixture was designed to protect the gastrointestine and hematopoietic organs and to promote recovery of the immune system against radiation damage. The mixture of 3 edible medicinal herbs was decocted with hot water and the extract was fractionated with ethanol. The preparation HemoHIM was made up with addition of ethanol-insoluble fraction to the total water extract. In vitro, HemoHIM, its polysaccharide and ethanol fractions protected lymphocytes against radiation and scavenged hydroxyl radicals. The proliferation of lymphocytes and bone marrow cells by HemoHIM was due to its polysaccharide fraction. In mice administered with the preparation (HemoHIM) before gamma-irradiation the jejunal crypt survival was increased and the apoptosis of crypt cells was decreased. HemoHIM administration increased the survival of bone marrow stem cells and promoted the repopulation of blood cells following irradiation. In the analysis of the repopulated lymphocyte subsets, B cells were firstly regenerated and then T cells were recovered in mice administrated with HemoHIM. The antibody production against T-dependent antigen DNP-KLH was augmented by HemoHIM in irradiated mice. Finally, oral or intraperitoneal administration of HemoHIM augmented the 30 day survival rate after irradiation. These results indicated that HemoHIM, a preparation of the herb mixture, protected the stem cells of self-renewal tissues and hematopoietic organs and promoted recovery of the immune system against radiation damage, thus increasing the survival following lethal irradiation. Since the preparation of herb mixture is a relatively nontoxic natural product, it might be a useful modifier for prevention and control of radiation damages.

Lambda-Cyhalothrin Nanosuspension Prepared by the Melt Emulsification-High Pressure Homogenization Method

Directory of Open Access Journals (Sweden)

Zhenzhong Pan

2015-01-01

Full Text Available The nanosuspension of 5% lambda-cyhalothrin with 0.2% surfactants was prepared by the melt emulsification-high pressure homogenization method. The surfactants composition, content, and homogenization process were optimized. The anionic surfactant (1-dodecanesulfonic acid sodium salt and polymeric surfactant (maleic rosin-polyoxypropylene-polyoxyethylene ether sulfonate screened from 12 types of commercially common-used surfactants were used to prepare lambda-cyhalothrin nanosuspension with high dispersity and stability. The mean particle size and polydispersity index of the nanosuspension were 16.01 ± 0.11 nm and 0.266 ± 0.002, respectively. The high zeta potential value of −41.7 ± 1.3 mV and stable crystalline state of the nanoparticles indicated the excellent physical and chemical stability. The method could be widely used for preparing nanosuspension of various pesticides with melting points below boiling point of water. This formulation may avoid the use of organic solvents and reduce surfactants and is perspective for improving bioavailability and reducing residual pollution of pesticide in agricultural products and environment.

COMPARISON OF THE QUALITY OF RNA ISOLATED FROM THE RAINBOW TROUT (Oncorhynchus mykiss TISSUE IN FOUR DIFFERENT WAYS

Directory of Open Access Journals (Sweden)

Irena Vardić

2004-03-01

Full Text Available Rapid and accurate diagnostic procedures for identification of reared fish diseases are important in order to reduce serious losses in relation of diseases outbrakes. Therefore, molecular biology methods are required for such types of investigations. First level in these experiments are DNA or RNA isolation. Tissue preparation for isolation of RNA, which is used in further RT-PCR (reverse transcription-polymerise chain reaction analysis is the key step on which is the whole process of analysis dependent. Our goal was to compare quality and integrity of RNA isolated from the rainbow trout tissue, which was prepared in four different ways: fresh tissue, frozen tissue, in formalin-fixed, paraffin embedded tissue as well as in methacarn-fixed, paraffin embedded tissue. Isolated RNA was analyzed in gel electrophoresis on non-denaturated, 1% agarose gel. Quality and integrity of RNA was proved by RT-PCR reaction with primers for ß-actin gene. Additional, prepared tissue was tested on presence of two fish viruses: viral haemorrhagic septicaemia (VHS virus and infectious haematopoietic necrosis (IHN virus in RT-PCR reaction with primers specific for these viruses. RNA isolated from fresh and frozen tissue was of high quality, integrity and quantity. RNA isolated from in methacarn-fixed, paraffin embedded tissue was quite disintegrated, but in RT-PCR with primers for ß-actin gave expected products. These products were absent after RT-PCR reaction with in formallin-fixed, paraffin-embedded tissue. That agrees with the facts from the literature about very agressive affect of formalin as a fixative on RNA in tissue. Inspected fish were not infected with VHS and IHN viruses and that was in agreement with results of clinical examination and pathological analysis. According to our knowledge, this is the first successful RNA isolation from in methacarn-fixed, paraffin embedded fish tissue. Isolated RNA can be used for further analysis in RT-PCR reaction. This

Preparation of vinyl acetate grafted natural rubber by irradiation method

Energy Technology Data Exchange (ETDEWEB)

Porntrairat, A.; Pattamaprom, C. [Center of Excellence on Natural Rubber Technology, Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani 12120 (Thailand)

2016-03-09

Improvement in properties of natural rubber could be done by several methods. In this research, gamma radiation technique, which is simple, accurate, easy to control and clean, was applied to enhance the properties of natural rubber (NR) in latex state. The purpose of this research is to study the appropriate condition for preparing grafted natural rubber latex by using irradiation method. Vinyl acetate monomers (VAc) were grafted onto natural rubber latex (NR-g-PVAc) at 0-10 kGys by gamma radiation from Cobalt-60 source at room temperature. Physical properties of grafted natural rubber such as chloroform number, swelling ratio and gel content were measured. The VAc content of NR-g-PVAc was investigated by titration and visualized by FTIR spectroscopy. The FTIR spectra of NR-g-PVAc prepared at 0-10 kGys showed characteristic peaks of the vinyl acetate confirming that VAc could be grafted onto natural rubber molecular chains effectively under appropriate irradiation conditions. From the result, radiation grafting was found to be a useful technique for grafting of vinyl acetate onto natural rubber.

Comprehensive evaluation and optimization of amplicon library preparation methods for high-throughput antibody sequencing.

Science.gov (United States)

Menzel, Ulrike; Greiff, Victor; Khan, Tarik A; Haessler, Ulrike; Hellmann, Ina; Friedensohn, Simon; Cook, Skylar C; Pogson, Mark; Reddy, Sai T

2014-01-01

High-throughput sequencing (HTS) of antibody repertoire libraries has become a powerful tool in the field of systems immunology. However, numerous sources of bias in HTS workflows may affect the obtained antibody repertoire data. A crucial step in antibody library preparation is the addition of short platform-specific nucleotide adapter sequences. As of yet, the impact of the method of adapter addition on experimental library preparation and the resulting antibody repertoire HTS datasets has not been thoroughly investigated. Therefore, we compared three standard library preparation methods by performing Illumina HTS on antibody variable heavy genes from murine antibody-secreting cells. Clonal overlap and rank statistics demonstrated that the investigated methods produced equivalent HTS datasets. PCR-based methods were experimentally superior to ligation with respect to speed, efficiency, and practicality. Finally, using a two-step PCR based method we established a protocol for antibody repertoire library generation, beginning from inputs as low as 1 ng of total RNA. In summary, this study represents a major advance towards a standardized experimental framework for antibody HTS, thus opening up the potential for systems-based, cross-experiment meta-analyses of antibody repertoires.

A simple method for measuring glucose utilization of insulin-sensitive tissues by using the brain as a reference

International Nuclear Information System (INIS)

Namba, Hiroki; Nakagawa, Keiichi; Iyo, Masaomi; Fukushi, Kiyoshi; Irie, Toshiaki

1994-01-01

A simple method, without measurement of the plasma input function, to obtain semiquantitative values of glucose utilization in tissues other than the brain with radioactive deoxyglucose is reported. The brain, in which glucose utilization is essentially insensitive to plasma glucose and insulin concentrations, was used as an internal reference. The effects of graded doses of oral glucose loading (0.5, 1 and 2 mg/g body weight) on insulin-sensitive tissues (heart, muscle and fat tissue) were studied in the rat. By using the brain-reference method, dose-dependent increases in glucose utilization were clearly shown in all the insulin-sensitive tissues examined. The method seems to be of value for measurement of glucose utilization using radioactive deoxyglucose and positron emission tomography in the heart or other insulin-sensitive tissues, especially during glucose loading. (orig.)

MULTIAGENT TECHNOLOGIES’ METHOD IN MANAGING BUSINESS-PROCESSES OF THE TECHNICAL PREPARING FOR PRODUCTION

Directory of Open Access Journals (Sweden)

P.N. Pavlenko

2005-02-01

Full Text Available  The method of managing the process of the extended productions technological preparation is given. The method is used for integrating the automated systems of industrial assignment of  CAD/CAM/SAPP and ERP systems.

Quantitative methods for reconstructing tissue biomechanical properties in optical coherence elastography: a comparison study

International Nuclear Information System (INIS)

Han, Zhaolong; Li, Jiasong; Singh, Manmohan; Wu, Chen; Liu, Chih-hao; Wang, Shang; Idugboe, Rita; Raghunathan, Raksha; Sudheendran, Narendran; Larin, Kirill V; Aglyamov, Salavat R; Twa, Michael D

2015-01-01

We present a systematic analysis of the accuracy of five different methods for extracting the biomechanical properties of soft samples using optical coherence elastography (OCE). OCE is an emerging noninvasive technique, which allows assessment of biomechanical properties of tissues with micrometer spatial resolution. However, in order to accurately extract biomechanical properties from OCE measurements, application of a proper mechanical model is required. In this study, we utilize tissue-mimicking phantoms with controlled elastic properties and investigate the feasibilities of four available methods for reconstructing elasticity (Young’s modulus) based on OCE measurements of an air-pulse induced elastic wave. The approaches are based on the shear wave equation (SWE), the surface wave equation (SuWE), Rayleigh-Lamb frequency equation (RLFE), and finite element method (FEM), Elasticity values were compared with uniaxial mechanical testing. The results show that the RLFE and the FEM are more robust in quantitatively assessing elasticity than the other simplified models. This study provides a foundation and reference for reconstructing the biomechanical properties of tissues from OCE data, which is important for the further development of noninvasive elastography methods. (paper)

Recent advances in sample preparation techniques and methods of sulfonamides detection - A review.

Science.gov (United States)

Dmitrienko, Stanislava G; Kochuk, Elena V; Apyari, Vladimir V; Tolmacheva, Veronika V; Zolotov, Yury A

2014-11-19

Sulfonamides (SAs) have been the most widely used antimicrobial drugs for more than 70 years, and their residues in foodstuffs and environmental samples pose serious health hazards. For this reason, sensitive and specific methods for the quantification of these compounds in numerous matrices have been developed. This review intends to provide an updated overview of the recent trends over the past five years in sample preparation techniques and methods for detecting SAs. Examples of the sample preparation techniques, including liquid-liquid and solid-phase extraction, dispersive liquid-liquid microextraction and QuEChERS, are given. Different methods of detecting the SAs present in food and feed and in environmental, pharmaceutical and biological samples are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Tau Oligomers as Pathogenic Seeds: Preparation and Propagation In Vitro and In Vivo.

Science.gov (United States)

Gerson, Julia E; Sengupta, Urmi; Kayed, Rakez

2017-01-01

Tau oligomers have been shown to be the main toxic tau species in a number of neurodegenerative disorders. In order to study tau oligomers both in vitro and in vivo, we have established methods for the reliable preparation, isolation, and detection of tau oligomers. Methods for the seeding of tau oligomers, isolation of tau oligomers from tissue, and detection of tau oligomers using tau oligomer-specific antibodies by biochemical and immunohistochemical methods are detailed below.

A Novel Nonlinear Parameter Estimation Method of Soft Tissues

Directory of Open Access Journals (Sweden)

Qianqian Tong

2017-12-01

Full Text Available The elastic parameters of soft tissues are important for medical diagnosis and virtual surgery simulation. In this study, we propose a novel nonlinear parameter estimation method for soft tissues. Firstly, an in-house data acquisition platform was used to obtain external forces and their corresponding deformation values. To provide highly precise data for estimating nonlinear parameters, the measured forces were corrected using the constructed weighted combination forecasting model based on a support vector machine (WCFM_SVM. Secondly, a tetrahedral finite element parameter estimation model was established to describe the physical characteristics of soft tissues, using the substitution parameters of Young’s modulus and Poisson’s ratio to avoid solving complicated nonlinear problems. To improve the robustness of our model and avoid poor local minima, the initial parameters solved by a linear finite element model were introduced into the parameter estimation model. Finally, a self-adapting Levenberg–Marquardt (LM algorithm was presented, which is capable of adaptively adjusting iterative parameters to solve the established parameter estimation model. The maximum absolute error of our WCFM_SVM model was less than 0.03 Newton, resulting in more accurate forces in comparison with other correction models tested. The maximum absolute error between the calculated and measured nodal displacements was less than 1.5 mm, demonstrating that our nonlinear parameters are precise.

Histone deacetylase 3 prepares brown adipose tissue for acute thermogenic challenge

DEFF Research Database (Denmark)

Emmett, Matthew J.; Lim, Hee-Woong; Jager, Jennifer

2017-01-01

Brown adipose tissue is a thermogenic organ that dissipates chemical energy as heat to protect animals against hypothermia and to counteract metabolic disease1. However, the transcriptional mechanisms that determine the thermogenic capacity of brown adipose tissue before environmental cold...

Application of tumbling melt granulation (TMG) method to prepare controlled-release fine granules.

Science.gov (United States)

Maejima, T; Kubo, M; Osawa, T; Nakajima, K; Kobayashi, M

1998-03-01

The tumbling melt granulation (TMG) method was applied to prepare controlled-release fine granules of diltiazem hydrochloride (DH). The entire process, from the preparation of the cores by the adherence of DH to the sucrose crystal to the subsequent coating of the controlled-release layer, was performed without using any solvent. A mixture of meltable material, talc, and ethylcellulose was used for the controlled-release layer and controlled-release fine granules approximately 400 microns in diameter were obtained with excellent producibility. The dissolution rate of DH from these fine granules was similar to that of a once-a-day dosage form obtained in the market; further, the dependency of the dissolution profile on pH of the media was less. Thus, it was concluded that this TMG method was very useful for preparing not only controlled-release beads of granule size (usually 500 to 1400 microns) but also fine granules.

A 2D Electromechanical Model of Human Atrial Tissue Using the Discrete Element Method

Directory of Open Access Journals (Sweden)

Paul Brocklehurst

2015-01-01

Full Text Available Cardiac tissue is a syncytium of coupled cells with pronounced intrinsic discrete nature. Previous models of cardiac electromechanics often ignore such discrete properties and treat cardiac tissue as a continuous medium, which has fundamental limitations. In the present study, we introduce a 2D electromechanical model for human atrial tissue based on the discrete element method (DEM. In the model, single-cell dynamics are governed by strongly coupling the electrophysiological model of Courtemanche et al. to the myofilament model of Rice et al. with two-way feedbacks. Each cell is treated as a viscoelastic body, which is physically represented by a clump of nine particles. Cell aggregations are arranged so that the anisotropic nature of cardiac tissue due to fibre orientations can be modelled. Each cell is electrically coupled to neighbouring cells, allowing excitation waves to propagate through the tissue. Cell-to-cell mechanical interactions are modelled using a linear contact bond model in DEM. By coupling cardiac electrophysiology with mechanics via the intracellular Ca2+ concentration, the DEM model successfully simulates the conduction of cardiac electrical waves and the tissue’s corresponding mechanical contractions. The developed DEM model is numerically stable and provides a powerful method for studying the electromechanical coupling problem in the heart.

Supported Pd Catalysts Prepared via Colloidal Method: The Effect of Acids

NARCIS (Netherlands)

Zhao, Yingnan; Jia, L.; Medrano Catalan, J.A.; Ross, J.R.H.; Ross, J.R.H.; Lefferts, Leonardus

2013-01-01

Organic capping agents are necessary for metallic nanoparticle preparation via colloidal method; however, complete removal of the capping agent and cleaning the metal surface is a well-known challenge in application. In this Article, we show that polyvinyl alcohol (PVA)-stabilized palladium