Relationship of optic disk topography and visual function in patients withlarge cup-to-disk ratios

Purpose. To determine the correlation of reduced retinal thickness in the central papillomacular bundle (CPB) to central visual function, including central retinal sensitivity and visual acuity, in glaucoma patients.Methods. This study enrolled 50 eyes of 50 patients with open-angle glaucoma who were carefully screened for comorbid conditions that can cause decreased central visual function, such as cataracts or macular diseases. We used a novel CPB analysis comprising a program for optical coherence tomography that measured RNFL thickness and GCC thickness in the CPB and divided lengthwise into three parts (upper, middle, and lower CPB). The relationship of these parameters, including conventional macular thickness, to visual field sensitivity in four central standard automated perimetry points (the central four thresholds) and BCVA was analyzed.Results. The two parameters most highly correlated with central four thresholds were macular GCCT and macular RNFLT. The two parameters most highly correlated with BCVA were middle CPB (mid-CPB) GCCT and mid-CPB RNFLT. A multiple regression analysis revealed that mid-CPB GCCT was an independent factor impacting central retinal thresholds and BCVA.Conclusions. Our results suggest that mid-CPB RNFLT and GCCT, parameters of a novel papillomacular bundle analysis, are candidate biomarkers of decreased central visual function in glaucomatous eyes.

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Studies on Leukemogenic and Sarcomagenic Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067777 ◽

1970 ◽

Vol 28 ◽

pp. 156-157

Author(s):

Leon Dmochowski

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Morphological Properties ◽

Mode Of Development ◽

Relationship Of ◽

The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

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The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085484 ◽

1991 ◽

Vol 49 ◽

pp. 236-237

Author(s):

J.R. Pfeiffer ◽

J.C. Seagrave ◽

C. Wofsy ◽

J.M. Oliver

Keyword(s):

Mast Cells ◽

Protein A ◽

Scattered Electron ◽

Ige Receptor ◽

Receptor Complexes ◽

Ige Binding ◽

Electron Imaging ◽

Small Clusters ◽

Relationship Of ◽

The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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Organization of transcription and pre-mRNA splicing within the mammalian cell nucleus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014021x ◽

1995 ◽

Vol 53 ◽

pp. 768-769

Author(s):

D.L. Spector ◽

S. Huang ◽

S. Kaurin

Keyword(s):

Rna Polymerase Ii ◽

Cell Nucleus ◽

Functional Organization ◽

Mrna Splicing ◽

Splicing Factors ◽

Interchromatin Granule Clusters ◽

Interchromatin Granule ◽

Nuclear Regions ◽

Relationship Of ◽

Perichromatin Fibrils

We have been interested in the organization of RNA polymerase II transcription and pre-mRNA splicing within the cell nucleus. Several models have been proposed for the functional organization of RNA within the eukaryotic nucleus and for the relationship of this organization to the distribution of pre-mRNA splicing factors. One model suggests that RNAs which must be spliced are capable of recruiting splicing factors to the sites of transcription from storage and/or reassembly sites. When one examines the organization of splicing factors in the nucleus in comparison to the sites of chromatin it is clear that splicing factors are not localized in coincidence with heterochromatin (Fig. 1). Instead, they are distributed in a speckled pattern which is composed of both perichromatin fibrils and interchromatin granule clusters. The perichromatin fibrils are distributed on the periphery of heterochromatin and on the periphery of interchromatin granule clusters as well as being diffusely distributed throughout the nucleoplasm. These nuclear regions have been previously shown to represent initial sites of incorporation of 3H-uridine.

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Locating Al in the DABCO catalyst before and after Al extraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174461 ◽

1990 ◽

Vol 48 (4) ◽

pp. 265-267

Author(s):

Kathleen B. Reuter

Keyword(s):

Active Site ◽

Inverse Relationship ◽

Transverse Direction ◽

Reaction Rate ◽

Acid Phosphate ◽

Fracture Surfaces ◽

Al Content ◽

Before And After ◽

Relationship Of

The reaction rate and efficiency of piperazine to 1,4-diazabicyclo-octane (DABCO) depends on the Si/Al ratio of the MFI topology catalysts. The Al was shown to be the active site, however, in the Si/Al range of 30-200 the reaction rate increases as the Si/Al ratio increases. The objective of this work was to determine the location and concentration of Al to explain this inverse relationship of Al content with reaction rate.Two silicalite catalysts in the form of 1/16 inch SiO2/Al2O3 bonded extrudates were examined: catalyst A with a Si/Al of 83; and catalyst B, the acid/phosphate Al extracted form of catalyst A, with a Si/Al of 175. Five extrudates from each catalyst were fractured in the transverse direction and particles were obtained from the fracture surfaces near the center of the extrudate diameter. Particles were also obtained from the outside surfaces of five extrudates.

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