The structure and distribution of proteochondroitin sulphate during the formation of chick embryo feather germs

Development ◽  
1987 ◽  
Vol 100 (3) ◽  
pp. 501-512 ◽  
Author(s):  
KUNIO KITAMURA
Keyword(s):  
Molecular Weight ◽  
Chick Embryo ◽  
Basement Membrane ◽  
The Other ◽  
Dorsal Skin ◽  
Superficial Dermis ◽  
Dermal Cells ◽  
Asymmetrically Distributed ◽  
Slow Turnover ◽  
Feather Buds

The dorsal skin of the chick embryo, in which feather germ forms, was found to synthesize two proteochondroitin sulphates, PCS-I and PCS-II and a proteoheparan sulphate, PHS. A monoclonal antibody (I3B9) was prepared against PCS-I, a higher molecular weight proteochondroitin sulphate. Distribution of PCS-I was immunohistochemically studied using I3B9. PCS-I was found in the epidermis, basement membrane and superficial dermis prior to formation of feather rudiments. As the feather rudiments formed, PCS-I was noted in a condensed area of dermal cells and in the basement membrane, while PCS-I decreased remarkably in the epidermal placode. The formation of feather buds resulted in a decrease in PCS-I in the region of dermal condensation and the basement membrane situated above this region. PCS-I was asymmetrically distributed in the feather filaments. The turnover of proteochondroitin sulphate was studied using autoradiography of [35S]sulphate. Proteochondroitin sulphate in the basement membrane and condensed dermis of the feather rudiments showed very slow turnover. On the other hand, the outgrowth of feather buds caused rapid turnover of proteochondroitin sulphate in the region of dermal condensation and basement membrane situated above this region. The mechanism for the uneven distribution of PCS-I during feather germ formation is discussed.

Dermal cells form strong adhesions to the basement membrane during the development of feather primordia in chick skin

Development ◽  
1984 ◽  
Vol 84 (1) ◽  
pp. 149-158
Author(s):  
Duncan Davidson
Keyword(s):  
Electron Microscope ◽  
Basement Membrane ◽  
Scanning Electron Microscope ◽  
Direct Measure ◽  
Dorsal Skin ◽  
Strong Adhesion ◽  
Dermal Cells ◽  
Scanning Electron

Experiments are described which provide a direct measure of the adhesion between dermis and epidermis during the development of feather primordia in chick dorsal skin in culture. The epidermis was peeled from the dermis and the surfaces so exposed were examined under the scanning electron microscope: regions of strong adhesion between the tissues were revealed as areas where their separation was incomplete. The results show that soon after primorida become morphologically distinct, cells from the surface of dermal condensations form adhesions to the basement membrane which are stronger than those between dermis and epidermis interplumar skin. These adhesions may help to hold the epidermis and dermis together during the outgrowth of the primordium.

Epidermal metaplasia of proamnionic epithelium induced by dorsal skin dermis in the chick embryo

Development ◽  
1972 ◽  
Vol 27 (1) ◽  
pp. 199-213
Author(s):  
Takeo Mizuno
Keyword(s):  
Chick Embryo ◽  
Superficial Layer ◽  
Epidermal Differentiation ◽  
Chick Embryos ◽  
Dorsal Skin ◽  
Somite Stage ◽  
Inductive Interaction ◽  
Dermal Cells

Proamnionic epithelium of the chick embryo cultivated directly on Wolff and Haffen's medium in the absence of mesenchymes fails to differentiate. Cultivation of the dorsal dermis of 6·5-day chick embryos in the absence of epithelium also results in lack of differentiation of dermal cells. When proamnionic epithelium taken from embryos before the 10-somite stage is cultivated combined with dorsal dermis of 6·5-day embryos for 6 days, the epithelium invariably undergoes metaplastic changes, forming stratified epidermis, sometimes with keratinized superficial layer. The underlying dermal cells are condensed and this often leads to the formation of feather germ-like structures. The competence of the epithelium for changing into the epidermis is gradually lost after the 10-somite stage, and the dorsal dermis from 8·5-day embryos is not very effective in inducing the epidermal metaplasia. Proamnionic epithelium cultivated on heat-killed dorsal dermis seems healthy but shows no sign of differentiation. Dorsal dermis combined with heat-killed proamnionic epithelium spreads and remains almost undifferentiated. These observations suggest that reciprocal induction mechanisms are involved in the epithelial and dermal differentiation. Cultivation of proamnionic epithelium with various heterologous mesenchymes or fragments of embryonic organs shows that this epithelium is only competent for epidermal differentiation when combined with dorsal dermis. When proamnion (proamnionic epithelium plus hypoblast) is directly combined with 6·5-day dorsal dermis it undergoes metaplastic changes. The same result is obtained when inverted (upside-down) proamnion is combined with the dermis. Hypoblast does not seem to affect the inductive interaction between the epithelium and the dorsal dermis.

vitreal cells and specialized phagocytes in the chick embryo retina: A TEM and SEM study

1990 ◽  
Vol 48 (3) ◽  
pp. 330-331
Author(s):  
M.A. Cuadros ◽  
M.J. Martinez-Guerrero ◽  
A. Rios
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Acid Phosphatase ◽  
Chick Embryo ◽  
Basement Membrane ◽  
Sem Images ◽  
Intimate Contact ◽  
Cellular Processes ◽  
Sem Study ◽  
Free Cells

In the chick embryo retina (days 3-4 of incubation), coinciding with an increase in cell death, specialized phagocytes characterized by intense acid phosphatase activity have been described. In these preparations, all free cells in the vitreal humor (vitreal cells) were strongly labeled. Conventional TEM and SEM techniques were used to characterize them and attempt to determine their relationship with retinal phagocytes.Two types of vitreal cells were distinguished. The first are located at some distance from the basement membrane of the neuroepithelium, and are rounded, with numerous vacuoles and thin cytoplasmic prolongations. Images of exo- and or endocytosis were frequent; the cells showed a well-developed Golgi apparatus (Fig. 1) In SEM images, the cells was covered with short cellular processes (Fig. 3). Cells lying parallel to or alongside the basement membrane are elongated. The plasma membrane is frequently in intimate contact with the basement membrane. These cells have generally a large cytoplasmic expansion (Fig. 5).

The Kidney and Fibrinolysis

1970 ◽  
Vol 24 (01/02) ◽  
pp. 026-032 ◽  
Author(s):  
N. A Marsh
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Enzyme System ◽  
Normal Animal ◽  
Fibrinolytic Enzyme ◽  
The Other ◽  
Exclusion Chromatography ◽  
Normal Urine ◽  
Renal Origin ◽  
Molecular Exclusion Chromatography

SummaryMolecular exclusion chromatography was performed on samples of urine from normal and aminonucleoside nephrotic rats. Normal urine contained 2 peaks of urokinase activity, one having a molecular weight of 22,000 and the other around 200,000. Nephrotic urine contained three peaks of activity with MW’s 126,000, 60,000 and 30,000. Plasma activator determined from euglobulin precipitate had a MW. in excess of 200,000. The results indicate that in the normal animal, plasma plasminogen activator does not escape into the urine in substantial quantities but under the conditions of extreme proteinuria there may be some loss through the kidney. The alteration in urokinase output in nephrotic animals indicates a greatly disordered renal fibrinolytic enzyme system.The findings of this study largely support the hypothesis that plasma plasminogen activator of renal origin and urinary plasminogen activator (urokinase) are different molecular species.

Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Human Urine ◽  
Gel Filtration ◽  
Chain Structure ◽  
The Other ◽  
Single Chain ◽  
Apparent Homogeneity ◽  
Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

Barricyclin D1—a dimeric ellagitannin with a macrocyclic structure—and accompanying tannins from Barringtonia racemosa

2021 ◽  
Author(s):  
Shinji Yoshikawa ◽  
Lih-Geeng Chen ◽  
Morio Yoshimura ◽  
Yoshiaki Amakura ◽  
Tsutomu Hatano ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Natural Resource ◽  
The Other ◽  
Hydrolysable Tannin ◽  
The Family ◽  
Macrocyclic Structure

Abstract Our examination of high molecular weight polyphenolic constituents in the leaves of Barringtonia racemosa of the family Lecythidaceae uncovered five previously undescribed ellagitannins. One, barringtin M1 (1), among them was a hydrolysable tannin monomer, while remaining four, barringtins D1 (2), D2 (3), D3 (4) and barricyclin D1 (5), were all dimers. Barricyclin D1 had a first macrocyclic structure formed from casuarictin (6) and tellimagrandin I (7), and the other ellagitannins had structures related to 5. Two additional known phenolics, valoneic acid dilactone (8) and schimawalin A (9), were also isolated from the leaves. These results suggested that the leaves of B. racemosa is a natural resource rich in hydrolysable tannin oligomers.

CO-ORDINATION COMPLEXES OF TITANIUM (IV) HALIDES: II. PREPARATION AND INFRARED SPECTRA OF THE COMPLEXES OF TITANIUM TETRACHLORIDE WITH DIESTERS OF α,ω-DICARBOXYLIC ACIDS AND COMPARISON WITH ANALOGOUS COMPLEXES OF ZIRCONIUM TETRACHLORIDE AND TIN TETRACHLORIDE

1961 ◽  
Vol 39 (11) ◽  
pp. 2343-2352 ◽  
Author(s):  
Ernest Rivet ◽  
Real Aubin ◽  
Roland Rivest
Keyword(s):  
Molecular Weight ◽  
Infrared Spectra ◽  
Titanium Tetrachloride ◽  
Complex Molecule ◽  
Dicarboxylic Acids ◽  
The Other ◽  
Zirconium Tetrachloride ◽  
Melting Points ◽  
Zirconium Complexes ◽  
Tin Tetrachloride

Co-ordination complexes between diesters of α,ω-dicarboxylic acids and titanium tetrachloride, tin tetrachloride, and zirconium tetrachloride have been prepared. The analytical results, the infrared spectra, the melting points, and the molecular-weight determinations indicate that for the titanium and zirconium complexes, two types of complexes are obtained, one having a general formula MX4•1 diester in which chelate rings from five to nine atoms are formed and the other one, 2MX4•1 diester in which there are two 4-membered rings per complex molecule. With tin tetrachloride only one type of complex is formed, which has two tin tetrachlorides and two diesters per complex molecule.

scholarly journals EFFECTS OF CYCLIC AMP AND SEPHADEX FRACTIONS OF CHICK EMBRYO EXTRACT ON CLONED RETINAL PIGMENTED EPITHELIUM IN TISSUE CULTURE

1974 ◽  
Vol 61 (2) ◽  
pp. 369-382 ◽  
Author(s):  
D. A. Newsome ◽  
R. T. Fletcher ◽  
W. G. Robison ◽  
K. R. Kenyon ◽  
G. J. Chader
Keyword(s):  
Molecular Weight ◽  
Chick Embryo ◽  
Adenosine Monophosphate ◽  
Cell Number ◽  
Retinal Pigmented Epithelium ◽  
Culture Dish ◽  
Adhesive Properties ◽  
Embryo Extract ◽  
Chick Embryo Extract ◽  
Pigmented Epithelium

The effects of dibutyryl cyclic 3',5'-adenosine monophosphate (BcAMP) and Sephadex G-25 fractions of chick embryo extract on the growth rate, morphology, and pigmentation of normal chick retinal pigmented epithelium (PE) were investigated. Seven cloned PE cell lines were each grown in modified Ham's F-12 medium alone (F-12), or in F-12 supplemented with either high molecular weight (H) or low molecular weight (L) fractions of chick embryo extract. Cells grown in F-12 alone or in L medium formed compact epithelial sheets, whereas cells grown in H had a fibrocytic appearance and formed poorly organized monolayers. In H plus BcAMP, cell morphology was more epithelioid than in H alone, and generally the monolayers appeared more differentiated. Under each of these three culture conditions, 2 x 10-4 M BCAMP retarded the increase in cell number and decreased the final number of cells per culture dish, but had little effect on plating efficiency. BcAMP also increased the rate of cell adhesion to a plastic substratum. Pigmentation was marked in cultures grown in F-12 or in L alone, but the addition of BcAMP dramatically reduced visible pigmentation. This effect was reversed when BcAMP was removed from the culture medium. Thus BcAMP modifies cell and colonial morphology, rate of cell accumulation, adhesive properties, and pigmentation of normal PE cells.

Effect on Polymer Chain Structure Caused by the Molar Fraction of 4-Hydroxybutyrate in Poly(3-hydroxybutyrate- co -4-hydroxybutyrate)

2012 ◽  
Vol 602-604 ◽  
pp. 776-780
Author(s):  
Zhi Qiang Li ◽  
Mei Li ◽  
Wei Jia Fan
Keyword(s):  
Molecular Weight ◽  
Intrinsic Viscosity ◽  
Polymer Chain ◽  
Molar Fraction ◽  
Chain Structure ◽  
The Other ◽  
Mean Square ◽  
Polarizing Microscope ◽  
Other Hand ◽  
The Mean

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)copolymer [P(3HB-co-4HB)] is a kind of biodegradable high molecular polymer produced by bioaccumulation. Because of the good biodegradability and biocompatibility, P(3HB-co-4HB)s have attracted wide attention . At first, the intrinsic viscosity[η] in good solvent of P(3HB-co-4HB) s with varying contents of 4HB was investigated in different temperature. Second, observed the changes of crystallization gathered state caused by the varying contents of 4HB by polarizing microscope. The results show that to the P(3HB-co-4HB)s in same molecular weight, the intrinsic viscosity[η] in good solvent barely changes when the mole fractions of 4HB increase. On the other hand, the mean square end to end distances[0] of macromolecular flexible chains increase with the mole fractions of 4HB. At the same time, the states of aggregation change from spherulites to dendrites. In this investigation, we discuss the reasons of the differences in depth.

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