STUDIES ON PROTEIN METABOLISM OF THE CORNEA: 1. THE DISTRIBUTION OF NITROGENOUS SOLIDS IN RABBIT CORNEAS

The normal rabbit cornea was found to contain an average of 22.7% solids (77.3% moisture), nitrogen comprising 14.7% of the dry weight. On a dry weight basis the cornea was composed of 10% as epithelium, 87% as stroma, and 3% as endothelium plus Descemet's membrane. The solid and nitrogen content of the stroma was nearly identical with that of the whole cornea. Endothelium plus Descemet's membrane and epithelium layers were relatively low in nitrogen content (10 and 12% of the dry weight, respectively) while the epithelium was relatively high in solids (30%). The partition of nitrogen, as protein and nonprotein, soluble or insoluble in physiological saline, was estimated for each corneal layer.

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Healing of Endothelium and Descemet's Membrane of Rabbit Cornea*

American Journal of Ophthalmology ◽

10.1016/0002-9394(58)90036-9 ◽

1958 ◽

Vol 46 (1) ◽

pp. 62-67 ◽

Cited By ~ 13

Author(s):

P.L. Morton ◽

H.L. Ormsby ◽

P.K. Basu

Keyword(s):

Rabbit Cornea ◽

Descemet's Membrane ◽

Descemet’S Membrane

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Relationships between Nitrogen Content in Leaf Dry Weight Basis and Absorption Capacity of Ammonium and Nitrate of Rice Seedlings Grown under Low Nutrient Concentrations.

Japanese Journal of Crop Science ◽

10.1626/jcs.66.329 ◽

1997 ◽

Vol 66 (2) ◽

pp. 329-330

Author(s):

Hiroshi EHARA ◽

Chikamasa KOMADA ◽

Masakazu GOTO ◽

Osamu MORITA

Keyword(s):

Nitrogen Content ◽

Dry Weight ◽

Absorption Capacity ◽

Weight Basis ◽

Nutrient Concentrations ◽

Rice Seedlings ◽

Leaf Dry Weight

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Effects of Benzalkonium Chloride on Pilocarpine-induced Opacity in Porcine Isolated Corneas

Alternatives to Laboratory Animals ◽

10.1177/026119299302100307 ◽

1993 ◽

Vol 21 (3) ◽

pp. 372-383

Author(s):

Haruyoshi Igarashi ◽

Yasunaga Katsuta ◽

Kayoko Sawa ◽

Yuu Chiba ◽

Michio Kozima ◽

...

Keyword(s):

Benzalkonium Chloride ◽

High Performance ◽

Physiological Saline ◽

Experimental Period ◽

Eye Drops ◽

In Vitro Test ◽

Endothelial Surface ◽

Descemet's Membrane ◽

Descemet’S Membrane

The incubation of isolated porcine corneas (intact, with the epithelium or endothelium plus Descemet's membrane removed, or with both the epithelium and endothelium plus Descemet's membrane removed) with solutions of pilocarpine HCl (5 X 10 4M or 5 x 10-3M) for four hours caused very little increase in opacity when compared with corneas incubated with physiological saline. However, at a higher concentration (5 x 10-2M), the application of pilocarpine to the endothelial surface, or to both the epithelial and endothelial surfaces of intact corneas, caused an obvious increase in opacity. The addition of the preservative benzalkonium chloride (BC; 0.005%) to pilocarpine solutions caused an increase in opacity, but in no circumstances did this appear to be other than an additive effect, since incubation with BC alone had an opacifying effect. This in vitro test confirms that pilocarpine is a safe drug for application as eye-drops. Studies using high performance liquid chromatography showed that BC increased the amount of pilocarpine passing through the cornea from the epithelial to the endothelial surface. A small amount of BC also passed through the cornea over the 4-hour experimental period.

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ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1976.38.1451 ◽

1976 ◽

pp. 213-225

Author(s):

I.M. Ritchie ◽

C.C. Boswell ◽

A.M. Badland

Keyword(s):

New Zealand ◽

Dry Weight ◽

Analytical Tool ◽

Species Level ◽

Weight Basis ◽

Plant Identification ◽

Leaf Fragment ◽

Research Division ◽

Or Groups ◽

Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

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Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments of the Brisbane River (Australia) – Preliminary Results

Water Science & Technology ◽

10.2166/wst.1989.0044 ◽

1989 ◽

Vol 21 (2) ◽

pp. 161-165 ◽

Cited By ~ 7

Author(s):

S. I. Kayal ◽

D. W. Connell

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

River Estuary ◽

Dry Weight ◽

Weight Basis ◽

Sediment Samples ◽

Preliminary Results ◽

Treated Sewage ◽

Polycyclic Aromatic ◽

Petroleum Refineries

Results of the analysis of twenty-three composite sediment samples revealed that PAHs are widely distributed in the Brisbane River estuary. Mean concentrations for individual compounds, on a dry weight basis, ranged from 0.03 µg/g for dibenz [ah] anthracene to 2.34 µg/g for fluoranthene. Observed PAH assemblages were rich in compounds having pyrolytic origins. However, the presence of petroleum derived compounds was indicative of the importance of petroleum as a PAH source in the estuary. Petroleum refineries, a coal loading terminal and a major treated sewage outfall located at the mouth were not indicated as major contributing sources of PAH pollution in the estuary.

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Mineral nutrition, dinitrogen fixation, and growth of Alnuscrispa and Alnusglutinosa

Canadian Journal of Forest Research ◽

10.1139/x85-138 ◽

1985 ◽

Vol 15 (5) ◽

pp. 855-861 ◽

Cited By ~ 14

Author(s):

G. Prégent ◽

C. Camiré

Keyword(s):

Mineral Nutrition ◽

Dry Weight ◽

Optimal Growth ◽

Maximum Growth ◽

Dinitrogen Fixation ◽

Weight Basis ◽

Critical Levels ◽

N Status

Invitro cultures of Alnuscrispa (Ait.) Pursh and Alnusglutinosa (L.) Gaertn. were used to estimate critical foliage levels of selected nutrients for optimal growth and dinitrogen (N2) fixation. For A. crispa to obtain 90% of maximum growth and N2 fixation, foliar levels of 0.12% P, 0.13% Mg, <0.31% K, and <0.04% Ca on a dry weight basis were needed. For A. glutinosa, the critical levels were 0.138% P, 0.10% Mg, 0.29% Ca, and ~0.20% K. From all the deficiencies observed, P had the more pronounced effects on N status of both species.

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Cleavage plane after liquid‐bubble preparation of Descemet’s membrane

Acta Ophthalmologica ◽

10.1111/aos.14716 ◽

2020 ◽

Author(s):

Annekatrin Rickmann ◽

Silke Wahl ◽

Alisa Katsen‐Globa ◽

André Schulz ◽

Norbert Pütz ◽

...

Keyword(s):

Cleavage Plane ◽

Descemet's Membrane ◽

Liquid Bubble ◽

Descemet’S Membrane

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Corneal pachymetry by AS-OCT after Descemet’s membrane endothelial keratoplasty

Scientific Reports ◽

10.1038/s41598-021-93186-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Friso G. Heslinga ◽

Ruben T. Lucassen ◽

Myrthe A. van den Berg ◽

Luuk van der Hoek ◽

Josien P. W. Pluim ◽

...

Keyword(s):

Deep Learning ◽

Endothelial Function ◽

Corneal Thickness ◽

Anterior Segment ◽

Anatomical Landmarks ◽

Endothelial Keratoplasty ◽

Descemet’S Membrane Endothelial Keratoplasty ◽

Descemet's Membrane ◽

Descemet’S Membrane ◽

Thickness Measurements

AbstractCorneal thickness (pachymetry) maps can be used to monitor restoration of corneal endothelial function, for example after Descemet’s membrane endothelial keratoplasty (DMEK). Automated delineation of the corneal interfaces in anterior segment optical coherence tomography (AS-OCT) can be challenging for corneas that are irregularly shaped due to pathology, or as a consequence of surgery, leading to incorrect thickness measurements. In this research, deep learning is used to automatically delineate the corneal interfaces and measure corneal thickness with high accuracy in post-DMEK AS-OCT B-scans. Three different deep learning strategies were developed based on 960 B-scans from 50 patients. On an independent test set of 320 B-scans, corneal thickness could be measured with an error of 13.98 to 15.50 μm for the central 9 mm range, which is less than 3% of the average corneal thickness. The accurate thickness measurements were used to construct detailed pachymetry maps. Moreover, follow-up scans could be registered based on anatomical landmarks to obtain differential pachymetry maps. These maps may enable a more comprehensive understanding of the restoration of the endothelial function after DMEK, where thickness often varies throughout different regions of the cornea, and subsequently contribute to a standardized postoperative regime.

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SOLUBLE SUGAR CHANGES OCCURRING DURING COLD HARDENING OF SPRING WHEAT, FALL RYE AND ALFALFA

Canadian Journal of Plant Science ◽

10.4141/cjps83-047 ◽

1983 ◽

Vol 63 (2) ◽

pp. 415-420 ◽

Cited By ~ 15

Author(s):

D. G. GREEN

Keyword(s):

Spring Wheat ◽

Soluble Sugar ◽

Soluble Sugars ◽

Dry Weight ◽

Weight Basis ◽

Cold Hardening ◽

Spring Type

Alfa, a relatively nonhardy alfalfa cultivar continued to accumulate, on a dry weight basis, fructose, α- and β-D-glucose, sucrose and maltose during the latter stages of cold hardening. Rambler, a hardier alfalfa cultivar conversely showed a decrease for these soluble sugars with hardening. Frontier rye, a very hardy winter habit cereal showed decreases in these soluble sugars plus melibiose during the same hardening period. These results support the hypothesis that hardy cereals and alfalfa undergo a decrease in soluble sugars with hardening, while less hardy cereals and alfalfa continue to increase in content of soluble sugars. Manitou wheat appeared not to fit this hypothesis and showed the decreased soluble sugars usually associated with hardy cultivars. Although Manitou is a spring type wheat, one of its parents, Thatcher, does contain gene(s) for the winter habit.Key words: Sugar, cold hardening, wheat, rye, alfalfa

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