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PubMed2003

Elevated levels of beta-catenin and fibronectin in three-dimensional collagen cultures of Dupuytren's disease cells are regulated by tension in vitro.

BACKGROUND: Dupuytren's contracture or disease (DD) is a fibro-proliferative disease of the hand that results in the development of scar-like, collagen-rich disease cords within specific palmar fascia bands. Although the molecular pathology of DD is unknown, recent evidence suggests that beta-catenin may play a role. In this study, collagen matrix cultures of primary disease fibroblasts show enhanced contraction and isometric tension-dependent changes in beta-catenin and fibronectin levels. METHODS: Western blots of beta-catenin and fibronectin levels were determined for control and disease primary cell cultures grown within stressed- and attached-collagen matrices. Collagen contraction was quantified, and immunocytochemistry analysis of filamentous actin performed. RESULTS: Disease cells exhibited enhanced collagen contraction activity compared to control cells. Alterations in isometric tension of collagen matrices triggered dramatic changes in beta-catenin and fibronectin levels, including a transient increase in beta-catenin levels within disease cells, while fibronectin levels steadily decreased to levels below those seen in normal cell cultures. In contrast, both fibronectin and beta-catenin levels increased in attached collagen-matrix cultures of disease cells, while control cultures showed only increases in fibronectin levels. Immunocytochemistry analysis also revealed extensive filamentous actin networks in disease cells, and enhanced attachment and spreading of disease cell in collagen matrices. CONCLUSION: Three-dimensional collagen matrix cultures of primary disease cell lines are more contractile and express a more extensive filamentous actin network than patient-matched control cultures. The elevated levels of beta-catenin and Fn seen in collagen matrix cultures of disease fibroblasts can be regulated by changes in isometric tension.

Biomechanical Phenomena↗

PubMed1996

Genetic characterization of Epimedium species using random amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (RFLP) diagnosis.

Total DNA was extracted from the leaves of seven Epimedium species grown in different places in Japan. Their genetic characterization was performed by DNA analyses of random amplified polymorphic DNA (RAPD) using 32 random primers having 10 base sequences, and by restriction fragment length polymorphism (RFLP). E. sagittatum and E. koreanum were easily distinguished by a representative amplified band pattern. It became evident that E. sagittatum had extremely different genetic composition compared to the other species. A dendrogram obtained from the similarity matrix by cluster analysis indicates that E. sagittatum can be completely isolated from the other species. Moreover, it became evident that E. grandiflorum var. higoense, E. trifoliatobinatum and E. koreanum are independent species, contrary to the previous assumption that they are subspecies or a variety. The geographical variation of E. sempervirens was confirmed by cluster analysis. E. diphyllum showed wide genetic variations, in spite of sampling from the same area.

Base Sequence↗

PubMed2006

Antireflection design concepts with equivalent layers.

Some novel concepts of designing antireflection (AR) coatings with equivalent layers are presented. As an introduction, essential papers concerning thin-film optics and AR designs are cited, and the AR problem and a previously introduced AR-hard design type are discussed. Based on the known matrix formalism, a potential AR region, an equivalent stack index, and an equivalent substrate index are defined to use the theory of stop-band suppression as a starting point for the design of broadband AR coatings. The known multicycle AR design type is identified as a typical solution to the AR problem if the presented approach is used.

Journal Article↗

PubMed2003

Tunable face-centered-cubic photonic crystal formed in holographic polymer dispersed liquid crystals.

We report on the fabrication and electro-optic measurements of face-centered-cubic (fcc) lattices in holographic polymer dispersed liquid-crystal materials. Four linearly polarized coherent plane waves were interfered to generate a fcc optical lattice that was subsequently and indefinitely recorded as an arrayed pattern of nanometer-sized liquid-crystal droplets (approximately 50 nm) at lattice nodes within a polymer matrix. Observed transmission spectra and Kossel diffraction curves are consistent with fcc crystal structure. A completely reversible 2% wavelength shift of the (+/- 111) stop band was observed on application of an electric field.

Journal Article↗

PubMed2005

Purification and characterization of Bacillus cereus protease suitable for detergent industry.

An extracellular alkaline protease from an alkalophilic bacterium, Bacillus cereus, was produced in a large amount by the method of extractive fermentation. The protease is thermostable, pH tolerant, and compatible with commercial laundry detergents. The protease purified and characterized in this study was found to be superior to endogenous protease already present in commercial laundry detergents. The enzyme was purified to homogeneity by ammonium sulfate precipitation, concentration by ultrafiltration, anion-exchange chromatography, and gel filtration. The purified enzyme had a specific activity of 3256.05 U/mg and was found to be a monomeric protein with a molecular mass of 28 and 31 kDa, as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and nondenaturing PAGE, respectively. Its maximum protease activity against casein was found to be at pH 10.5 and 50 degrees C. Proteolytic activity of the enzyme was detected by casein and gelatin zymography, which gave a very clear protease activity zone on gel that corresponded to the band obtained on SDS-PAGE and nondenaturing PAGE with a molecular mass of nearly 31 kDa. The purified enzyme was analyzed through matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) and identified as a subtilisin class of protease. Specific serine protease inhibitors, suggesting the presence of serine residues at the active site, inhibited the enzyme significantly.

Bacillus cereus↗

PubMed1992

Ultra-high-resolution scanning electron microscopic studies on the sarcoplasmic reticulum and mitochondria of the rat intrafusal muscle fibers. Part II: The extracapsular region.

The three-dimensional structure of the transverse-axial tubular system, sarcoplasmic reticulum (SR) and mitochondria in the extracapsular region of the intrafusal muscle fibers of the rat lumbrical muscle was observed by ultra-high-resolution scanning electron microscopy after removal of the cytoplasmic matrix by the osmium-DMSO-osmium procedure. Nuclear chain fibers possessed thick to moderately sized column-forming mitochondria with occasional I-band branches. The transverse tubules (T-tubules) running at the level of the A-band side of the A-I junction were sandwiched between two large terminal cisternae for most of their length, forming triads. The sarcotubules arising from the terminal cisternae formed single-layered networks at the A-band level, and well developed, double-layered, three-dimensional networks at the I-band level. Nuclear bag1 fibers possessed slender column-forming mitochondria devoid of I-band branches. The T-tubules were located at the level of the A-I junction. Both the T- and the axial-tubules were occasionally coupled with small terminal cisternae, forming dyads or triads. At the I-band level, the SR was well developed and formed single layered networks, but at the A-band level only a few longitudinally arranged sarcotubules and axial tubules were observed. Nuclear bag2 fibers contained medium to large diameter column-forming mitochondria without I-band branches. The T-tubules ran at the level of the A-band adjacent to the A-I junction, and were coupled at some intervals with terminal cisternae of various lengths. Swollen, large terminal cisternae were frequently seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2001

Purification and characterization of a hemagglutinin isolated from the leaves of Chenopodium (Chenopodium amaranticolor).

A hemagglutinin was isolated and purified from the leaves of Chenopodium (Chenopodium amaranticolor) using ion-exchange chromatography and affinity chromatography on fetuin-agarose matrix. It agglutinated rabbit erythrocytes. The hemagglutinin had a native molecular mass of 58 kDa, as estimated by gel filtration and showed a single band of molecular mass of 33 kDa on SDS-PAGE. It showed hemagglutination activity over the pH range 3-12 and was found to be stable up to 70 degrees C. On isoelectrofocussing, the pI of this hemagglutinin was estimated to be 5.25. However, it was found to contain seven charge variants when isoelectrofocussing was performed in presence of 6M urea.

Chenopodium↗

PubMed2003

Nuclearia pattersoni sp. n. (Filosea), a new species of amphizoic amoeba isolated from gills of roach (Rutilus rutilus), and its rickettsial endosymbiont.

A new species of amphizoic amoeba, Nuclearia pattersoni sp. n., isolated from gills of Rutilus rutilus L. is described. It is characterised by elongate flattened trophozoites of irregular shape. The longer dimension of their bodies is 13.2 (11.0-15.7) microm. Filopodia radiating mostly from the poles are 2 to 2.5 times longer than the body. The diameter of less frequently observed spherical trophozoites is 8.2-10.8 microm; their filopodia radiate to all directions. Cyst-like stages have shorter pseudopodia that arise from one pole only. The surface of locomotive forms from agar plate cultures has a thin amorphous glycocalyx, while most cells are covered by two layers of extracellular matrix. Mitochondria have flattened cristae, dictyosomes are located in the perinuclear zone. A conspicuous ultrastructural feature of the morphologically similar N. simplex, perinuclear striated band, is not present. Light microscopic and ultrastructural data are completed with the sequence of SSU rRNA gene and phylogenetic analysis including sequences of related taxa. The bacterial endosymbiont found in N. pattersoni type strain RR2G2 is assigned to the genus Rickettsia.

Amoeba↗

PubMed1990

Phytochrome from the green alga Mesotaenium caldariorum. Purification and preliminary characterization.

A method to purify the phytochrome photoreceptor from the unicellular green alga Mesotaenium caldariorum is presented. Preparative scale formation of algal protoplasts and controlled osmotic cell lysis have permitted separation of intact organelles from the phytochrome-enriched soluble protein fraction. We have utilized the observation that red light-absorbing (Pr) and far-red light-absorbing (Pfr) forms of phytochrome are differentially retained on an anion exchange matrix to purify M. caldariorum phytochrome to apparent homogeneity. M. caldariorum phytochrome preparations with A650/A280 ratios greater than 0.78 exhibit a single 120-kDa band on silver-stained sodium dodecyl sulfate-polyacrylamide gels. Immunoblot analyses using a cross-reactive pea phytochrome monoclonal antibody reveal that 1) the 120-kDa band represents the full-length polypeptide, 2) phytochrome is predominantly localized in the algal cytoplasm, and 3) there are 150,000-250,000 phytochrome molecules/cell. Steric exclusion high pressure liquid chromatography analysis under nondenaturing conditions indicates that M. caldariorum phytochrome has an apparent mass of 355 kDa. The absorption maxima for Pr and Pfr are 650 and 722 nm, respectively. Both are blue-shifted compared with those of phytochromes from dark-grown angiosperm tissue. The molar absorption coefficient for Pr at 650 nm is 86,800 +/- 2800 liter mol-1 cm-1, which is lower than that of higher plant phytochromes. The significance of the similarities and differences of the molecular properties of phytochromes from M. caldariorum and higher plant sources is discussed.

Chlorophyta↗

PubMed1987

Congenital leukonychia striata.

Leukonychia striata of a unique appearance and distribution is described in a 51-year-old woman. Histopathologic examination of a specimen from the nail plate revealed a transverse band of parakeratosis on the ventral surface. Disturbance in keratinization on the nail plate is presumed to be secondary to abnormalities in the nail matrix. We review briefly the classification and pathogenesis of leukonychia, an interesting aberration in nail plate keratinization.

Female↗

PubMed1989

Comparison of a 550,000 dalton cartilage matrix glycoprotein in cartilage from immature and mature dogs.

Cartilage matrix glycoprotein is a disulfide bonded 550,000 dalton protein found in cartilage and in the vitreous of the eye. Immunofluorescence studies using a specific antiserum to this glycoprotein have previously demonstrated a difference between the topographic distribution of staining for cartilage matrix glycoprotein in cartilage from immature and mature animals. Using a polyclonal antiserum to cartilage matrix glycoprotein, we studied this protein in cartilage from normal immature and mature dogs to determine if it changes with maturation. Cartilage matrix glycoprotein from immature canine cartilage migrates as a doublet, with apparent molecular weights of 100-116,000, regardless of its state of reduction, and is immunologically cross reactive with cartilage matrix glycoprotein from adult canine cartilage. Cartilage matrix glycoprotein from mature canine cartilage is disulfide bonded before reduction with 2-mercaptoethanol and its 116,000 Da subunit migrates as a single band after reduction.

Aging↗

PubMed1993

[Adhesion ultrastructures of mononuclear cells in experimentally-induced silicotic granuloma].

Experimental silicosis was induced by intratracheal infusions of 1 ml saline containing 50 mg standard silica (less than 5 microns diameter) in Sprague-Dawley rats. The lung tissues were observed histologically and ultrastructurally from half an hour up to 4 months. Macrophages, neutrophils, desquamated cells and their debris piled up around the alveolar ducts where the central cores of silicotic granuloma appeared. The granuloma became apparent by day 4 after the infusion and were covered by type II alveolar epithelial cells and bronchiolar cuboidal epithelial cells. Macrophages, fibroblasts and epithelial cells began to react to the antibody against proliferating cell nuclear antigen (PCNA) indicating self-replication on day 1. Macrophages in the granuloma made a close interdigitation with adjacent macrophages, and they gradually formed subplasmalemmal linear densities (SPLD) as paired forms between adjacent plasma membranes, and unpaired forms facing the interstitial matrix. SPLD were composed of linear densities with actin-like microfilaments along the leaflets of plasma membrane and were associated with extracellular dense bands which resembled a limited length of basement membrane. Interdigitation and SPLD structures were quite rare on day 1, but the number of macrophages with both structures increasingly appeared. The frequency of SPLD in macrophages also increased on a time course of granuloma maturation up to 4 months. Thus SPLD, which were originally found in the mononuclear phagocytes including macrophages, epithelioid cells and multi-nucleated giant cells, particularly in immune granuloma of man, also played a basic role in immobilizing macrophages in lesions of silica-induced granulomas.

Animals↗

PubMed1998

A method for examining the chemical basis for bone disease: synchrotron infrared microspectroscopy.

Infrared microspectroscopy combines microscopy and spectroscopy for the purpose of chemical microanalysis. Light microscopy provides a way to generate and record magnified images and visibly resolve microstructural detail. Infrared spectroscopy provides a means for analyzing the chemical makeup of materials. Combining light microscopy and infrared spectroscopy permits the correlation of microstructure with chemical composition. Inherently, the long wavelengths of infrared radiation limit the spatial resolution of the technique. However, synchrotron infrared radiation significantly improves both the spectral and spatial resolution of an infrared microspectrometer, such that data can be obtained with high signal-to-noise at the diffraction limit, which is 3-5 microm in the mid-infrared region. In this study, we use infrared microspectroscopy to study the chemical composition of bone using two mapping methods. In the osteon method, linear maps are collected from the center of an osteon (newer bone) to the periphery (older bone) and their chemical compositions are compared. In the transverse method, applied specifically to subchondral bone, line maps are collected from the edge of the articular cartilage (older bone) to the marrow space (newer bone). A significant advantage of infrared microspectroscopy over other chemical methods is that the bone does not need to be homogenized for testing; we are able to study cross-sectional samples of bone in situ at a resolution better than 5 microm and compare the results with morphological findings on stained serial sections immediately adjacent to those examined by infrared microspectroscopy. The infrared absorption bands of bone proteins and mineral are sensitive to mineral content (i.e. carbonate, phosphate, acid phosphate), mineral crystallinity and the content/nature of the organic matrix. In this study, they are analyzed as a function of (1) age, i.e. distance with respect to the center of an osteon, and (2) morphology, i.e. cortical versus cancellous (notably subchondral) bone. Results show that the protein/mineral ratio is higher in younger bone. As bone matures, mineralization increases, as does carbonate substitution into the hydroxyapatite lattice. Finally, most of the changes in chemical composition of bone occur within 20 microm of the site of new bone growth, e.g. the center of an osteon, demonstrating the need for the high spatial resolution achieved only with the use of a synchrotron infrared source.

Animals↗

PubMed2005

Quantitative analysis and comparative regional investigation of the extracellular matrix of the porcine temporomandibular joint disc.

Characterization of the extracellular matrix of the temporomandibular joint (TMJ) disc is crucial to advancing efforts in tissue engineering the disc. However, the current literature is incomplete and often contradictory in its attempts to describe the nature of the TMJ disc matrix. The aim of this study was to identify the variation of key matrix components along the three axes of the porcine disc using ELISAs to quantify these matrix components, immunohistochemistry to identify their regional distribution, and SEM to examine collagen fiber diameter and orientation. The overall GAG content of the TMJ disc (including the dermatan sulfate proteoglycans) was 5.3+/-1.2% of the dry weight. Chondroitin sulfate, which comprised 74% of this total GAG content, was 4.4, 8.2, and 164 times more abundant than dermatan sulfate proteoglycan, keratan sulfate, and hyaluronic acid, respectively. In general, these GAGs were most concentrated in the intermediate zone of the TMJ disc, appearing in dense clusters, and least concentrated in the posterior band. Additionally, chondroitin sulfate was more abundant medially than laterally. Collagen II was discovered in trace amounts, with higher relative amounts in the intermediate zone. Collagen fibers were observed to run primarily in a ring-like fashion around the periphery of the disc and anteroposteriorly through the intermediate zone, with a mean fiber diameter of 18+/-9 mum. Characterization studies of the TMJ disc, including prior biomechanical and cell studies along with the current study of the extracellular matrix, collectively reveal a distinct character of the intermediate zone of the disc compared to its anterior and posterior bands.

Animals↗

PubMed2002

Matrix metalloproteinase (MMP)-2 and MMP-9 activities in human seminal plasma.

We report on the existence of two kinds of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, in human seminal plasma. Partial purification of the proteinases was achieved by two steps, consisting of chromatography on a gel-filtration column and then on a gelatin affinity column. Proteinase activities in the chromatography extracts were shown to hydrolyse a fluorescent substrate specific to MMPs (Dnp-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH2). The proteinases were detected using gelatin-zymography, but were not detected using casein-zymography, and were also inhibited by EDTA, EGTA and o-phenanthroline. Molecular weights of the proteinases were determined by SDS-PAGE, gelatin-zymography and Western blot to be approximately 92, 84, 72, 67, 52 and 45 kDa. Gelatin-zymography showed three major bands of activity at 72, 67 and 52 kDa and minor bands at 92, 84 and 45 kDa. Apart from the two smallest bands, these proteinases were all recognized by the polyclonal antibodies for MMP-2 or MMP-9. These results indicate that two kinds of pro-form and active-form matrix metalloproteinases, MMP-2 and MMP-9, and their degradation products, are present in human seminal plasma.

Chromatography↗

PubMed1983

Isoelectric focusing in agarose: classification of genetic variants of alpha 1-antitrypsin.

Polyacrylamide has been the matrix of choice for isoelectric focusing owing to the virtual absence of electroendosmosis in this medium. Certain inherent limitations associated with polyacrylamide have prompted some investigators to use low-electroendosmosis agarose for isoelectric focusing, but with limited success thus far. We have developed a method for isoelectric focusing in agarose for the classification of alpha 1-antitrypsin variants. Sera are applied directly to agarose gels containing a pH 4-5 ampholyte mixture, focused for less than 1 h, and directly immunofixed. Resolution of major bands is equivalent to polyacrylamide, and Pi M subtypes can be distinguished without the use of a separator. This application demonstrates the high resolution of isoelectric focusing in agarose, a more practical and convenient matrix than polyacrylamide.

Acrylic Resins↗

PubMed1995

Proteoglycans are present in the transverse tubule system of skeletal muscle.

The transverse tubule system (T-tubule, T-system) of skeletal muscle is a membranous network that penetrates the interior of myofibers. The T-system is continuous with the sarcolemma and therefore provides a path for membrane excitation to reach internal myofibrils. In this study we demonstrate that T-tubules in elasmobranch fish, frog, and rat skeletal muscle contain a matrix of chondroitin sulfate proteoglycans. We used anti-T1, a mouse monoclonal antibody that recognizes a rare chondroitin sulfate epitope, for immunolocalization and biochemical studies. First, we find that T1 immunoreactivity colocalizes with a T-tubule marker, the dihydropyridine receptor alpha 2 subunit, in both frog and fish muscle. Secondly, the distribution of T1 immunoreactivity exactly matches the different distribution of T-tubules in rat and frog muscle. In rat muscle, two bands of T1 immunoreactivity are detected per sarcomere, a distribution that corresponds to the T-tubules located at the two A-I junctions of each sarcomere. In frog muscle, we detect one band of T1 immunoreactivity per sarcomere that corresponds to the one T-tubule per sarcomere located at the Z line. Lastly, we have isolated and biochemically characterized T1 antigenicity from fish skeletal muscle. Like extracellular matrix proteoglycans of cartilage, T1 antigenicity requires denaturing conditions to be solubilized. In fish muscle, two chondroitin sulfate proteoglycans bear T1: a heavily glycosylated proteoglycan with a molecular mass of about 1000 kDa, and a smaller proteoglycan that has a mobility on SDS-PAGE like a protein of molecular mass 280 kDa. We propose that proteoglycans function as structural components in the T-system. The proteoglycans may form a matrix, like the one formed by the cartilage proteoglycans they resemble, that can withstand the cytosolic osmotic pressures present in muscle cells and therefore may prevent the T-tubule from collapsing. We present a quantitative argument in support of this hypothesis.

Animals↗

PubMed1988

Heparan sulfate proteoglycan from the extracellular matrix of human lung fibroblasts. Isolation, purification, and core protein characterization.

Confluent cultured human lung fibroblasts were labeled with 35SO4(2-). After 48 h of labeling, the pericellular matrix was prepared by Triton X-100 and deoxycholate extraction of the monolayers. Heparan sulfate proteoglycan (HSPG) accounted for nearly 80% of the total matrix [35S]proteoglycans. After solubilization in 6 M guanidinium HCl and cesium chloride density gradient centrifugation, the majority (78%) of these [35S] HSPG equilibrated at an average buoyant density of 1.35 g/ml. This major HSPG fraction was purified by ion-exchange chromatography on Mono Q and by gel filtration on Sepharose CL-4B, and further characterized by gel electrophoresis and immunoblotting. Intact [35S]HSPG eluted with Kav 0.1 from Sepharose CL-4B, whereas the protein-free [35S]heparan sulfate chains, obtained by alkaline borohydride treatment of the proteoglycan fractions, eluted with Kav 0.45 (Mr approximately 72,000). When analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography, core (protein) preparations, obtained by heparitinase digestion of 125I-labeled HSPG fractions, yielded one major labeled band with apparent molecular mass of approximately 300 kDa. Reduction with beta-mercaptoethanol slightly increased the apparent Mr of the labeled band, suggesting a single polypeptide structure and the presence of intrachain disulfide bonds. Immunoadsorption experiments and immunostaining of electrophoretically separated heparitinase-digested core proteins with monoclonal antibodies raised against matrix and cell surface-associated HSPG suggested that the major matrix-associated HSPG of cultured human lung fibroblasts is distinct from the HSPG that are anchored in the membranes of these cells. Binding studies suggested that this matrix HSPG interacts with several matrix components, both through its glycosaminoglycan chains and through its heparitinase-resistant core. Core (protein) interactions seem to be responsible for the association of the proteoglycan with the extracellular matrix.

Antibodies, Monoclonal↗