Synthesis of extracellular matrix components by human ciliary muscle cells in culture

The production and spatial organization of connective tissue components in ciliary muscle cell cultures was studied with immunohistochemical and ultrastructural methods. Antibodies against collagen types IV and VI, fibronectin and laminin were used. Laminin stains as pericellular network surrounding individual muscle cells. Type IV collagen shows positive cytoplasmic staining and only small foci of extracellular immunofluorescence. Staining for type VI collagen and fibronectin is seen near the ends of the bipolar cells, while the lateral sides of the cells remain unstained. Electronmicroscopy shows that cultured ciliary muscle cells are surrounded by an incomplete basal lamina. In addition, bundles of 5-20 nm thick extracellular microfibrils are seen. The bundles are oriented parallel to the axis of the cells and are in close contact with the cell membrane in areas where membrane-bound dense bands are formed. Immunoelectronmicroscopy indicates that the bundles contain fibronectin and type VI collagen fibrils. While the fibronectin fibrils approach the cell membrane directly, type VI collagen fibrils are usually separated from the cell membrane by fine fibrillous material of different nature. Quality and spatial organization of the extracellular material in ciliary muscle cell cultures shows marked similarities with the extracellular matrix of ciliary muscle in situ

Noncommuting spherical coordinates

Restricting the states of a charged particle to the lowest Landau level introduces a noncommutativity between Cartesian coordinate operators. This idea is extended to the motion of a charged particle on a sphere in the presence of a magnetic monopole. Restricting the dynamics to the lowest energy level results in noncommutativity for angular variables and to a definition of a noncommuting spherical product. The values of the commutators of various angular variables are not arbitrary but are restricted by the discrete magnitude of the magnetic monopole charge. An algebra, isomorphic to angular momentum, appears. This algebra is used to define a spherical star product. Solutions are obtained for dynamics in the presence of additional angular dependent potentials.Comment: 5 pages, RevTex4 fil

Immunohistochemical characterization of the 'intimal proliferation' phenomenon in Sneddon's syndrome and essential thrombocythaemia

Cellular changes were immunocytochemically characterized in skin vessels of five patients with idiopathic generalized racemose livedo (Sneddon's syndrome), and one patient with localized racemose livedo associated with essential thrombocythaemia. Antibodies against alpha-smooth muscle-actin, tropomyosin, desmin, vimentin, factor VIII-related antigen, human endothelial cells (CD31), human macrophages (CD68), and HLA-DR positive cells (CR3/43) were used. Conventional light microscopy showed, in all cases, intimal thickening of ascending arteries and arterioles as a result of an accumulation of cells and extracellular hyalinized material. None of the specimens showed infiltration with polymorphonuclear leucocytes or macrophages. The cells in the region of the intimal hyperplasia showed intense positive immunostaining for alpha-smooth muscle actin and tropomyosin. Staining for the intermediate filament desmin was localized to the resident smooth muscle cells of the media, whereas staining for vimentin was found in all types of cells in both the intima and media. Positive immunostaining for factor VIII-related antigen and CD31 was strictly confined to the endothelial cells lining the narrowed lumina of the vessels. No positive staining with either antibody was observed in totally occluded vessels. Cells in the subintimal space did not show reactivity for CD68 in any of the specimens, but two cases showed solitary cells with positive staining for HLA-DR in this region. There were no differences in staining pattern between Sneddon's syndrome and essential thrombocythaemia with any of the antibodies. Our results support the assumption that the 'intimal proliferation' in both diseases is caused by colonization of the subendothelial space with contractile cells of possible smooth muscle origin.(ABSTRACT TRUNCATED AT 250 WORDS

Flux- and volume-limited groups/clusters for the SDSS galaxies: catalogues and mass estimation

We provide flux-limited and volume-limited galaxy group and cluster catalogues, based on the spectroscopic sample of the SDSS data release 10 galaxies. We used a modified friends-of-friends (FoF) method with a variable linking length in the transverse and radial directions to identify as many realistic groups as possible. The flux-limited catalogue incorporates galaxies down to m_r = 17.77 mag. It includes 588193 galaxies and 82458 groups. The volume-limited catalogues are complete for absolute magnitudes down to M_r = -18.0, -18.5, -19.0, -19.5, -20.0, -20.5, and -21.0; the completeness is achieved within different spatial volumes, respectively. Our analysis shows that flux-limited and volume-limited group samples are well compatible to each other, especially for the larger groups/clusters. Dynamical mass estimates, based on radial velocity dispersions and group extent in the sky, are added to the extracted groups. The catalogues can be accessed via http://cosmodb.to.ee and the Strasbourg Astronomical Data Center (CDS).Comment: 16 pages, 18 figures, 2 tables, accepted for publication in A&

Elektronenmikroskopische und inununhistochemische Untersuchungenzur augendrucksenkenden Wirkung von Prostaglandin F2alpha [Electron microscopy and immunohistochemical studies of the intraocular pressure lowering effect of prostaglandin F2 alpha]

Topically applied prostaglandin F2 alpha (PGF2 alpha) has been shown to lower intraocular pressure in cynomolgus monkeys. In this study the morphological changes following topical treatment of seven cynomolgus monkeys with 4 micrograms PGF2 alpha isopropylester for 5-8 days were investigated and compared with the eyes of five normal animals. Quantitative light microscopical, ultrastructural and immunhistochemical methods were used. No cellular signs of inflammation were seen in any of the eyes. Slight edema in the most anterior part of the ciliary processes occurred in most eyes, but only in parts of the circumference. The most pronounced change was dilation of the intramuscular spaces within the ciliary muscle. No changes were observed in the extracellular matrix within the muscle bundles, which consist partly of type IV and VI collagen, laminin and fibronectin. In the connective tissue between the muscle bundles, loss of collagen type I and III fibrils was observed. Additionally, macrophages were found with phagolysosomes containing phagocytized collagen fibrils. We suggest that loss of extracellular material leads to a widening of the uveoscleral outflow pathways of ciliary muscle and thereby to a reduction in intraocular pressure

Progressive retinal degeneration and glial activation in the Cln6nclf mouse model of neuronal ceroid lipofuscinosis : a beneficial effect of DHA and Curcumin supplementation

Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative lysosomal storage disorders characterized by vision loss, mental and motor deficits, and spontaneous seizures. Neuropathological analyses of autopsy material from NCL patients and animal models revealed brain atrophy closely associated with glial activity. Earlier reports also noticed loss of retinal cells and reactive gliosis in some forms of NCL. To study this phenomenon in detail, we analyzed the ocular phenotype of CLN6nclf mice, an established mouse model for variant-late infantile NCL. Retinal morphometry, immunohistochemistry, optokinetic tracking, electroretinography, and mRNA expression were used to characterize retinal morphology and function as well as the responses of Müller cells and microglia. Our histological data showed a severe and progressive degeneration in the CLN6nclf retina co-inciding with reactive Müller glia. Furthermore, a prominent phenotypic transformation of ramified microglia to phagocytic, bloated, and mislocalized microglial cells was identified in CLN6nclf retinas. These events overlapped with a rapid loss of visual perception and retinal function. Based on the strong microglia reactivity we hypothesized that dietary supplementation with immuno-regulatory compounds, curcumin and docosahexaenoic acid (DHA), could ameliorate microgliosis and reduce retinal degeneration. Our analyses showed that treatment of three-week-old CLN6nclf mice with either 5% DHA or 0.6% curcumin for 30 weeks resulted in a reduced number of amoeboid reactive microglia and partially improved retinal function. DHA-treatment also improved the morphology of CLN6nclf retinas with a preserved thickness of the photoreceptor layer in most regions of the retina. Our results suggest that microglial reactivity closely accompanies disease progression in the CLN6nclf retina and both processes can be attenuated with dietary supplemented immuno-modulating compounds

Cherenkov radiation by particles traversing the background radiatio n

High energy particles traversing the Universe through the cosmic microwave backgroung radiation can, in principle, emit Cherenkov radiation. It is shown that the energy threshold for this radiation is extremely high and its intensity would be too low due to the low density of the "relic photons gas" and very weak interaction of two photons.Comment: 6 pages, LATEX, no Figs.; to be published in JETP Lett. 75 (N4) (2002

Possible quantum kinematics. II. Non-minimal case

The quantum analogs of the N-dimensional Cayley-Klein spaces with different combinations of quantum and Cayley-Klein structures are described for non-minimal multipliers, which include the first and the second powers of contraction parameters in the transformation of deformation parameter. The noncommutative analogs of (N-1)-dimensional constant curvature spaces are introduced. Part of these spaces for N=5 are interpreted as the noncommutative analogs of (1+3) space-time models. As a result the wide variety of the quantum deformations of realistic kinematics are suggested.Comment: 13 pages, no figure