scholarly journals WOUND HEALING AND COLLAGEN FORMATION

1962 ◽  
Vol 12 (3) ◽  
pp. 533-551 ◽  
Author(s):  
Russell Ross ◽  
Earl P. Benditt
Keyword(s):  
Electron Microscopy ◽  
Wound Healing ◽  
Protein Synthesis ◽  
Small Groups ◽  
Guinea Pigs ◽  
Light And Electron Microscopy ◽  
Dense Matter ◽  
Skin Wounds ◽  
Intercellular Spaces ◽  
Collagen Formation

The sequence encountered in healing skin wounds in scorbutic guinea pigs has been examined by methods of light and electron microscopy. Linear incisions in the skin of female guinea pigs fed a scorbutigenic diet were allowed to heal. The wounds were removed for examination at 1, 3, 5, 9, and 14 days after wounding. The fibroblasts of the scorbutic wounds differ from those of the controls in three major aspects. First, little collagen is present within the intercellular spaces, although small groups of individual collagen fibrils can be found adjacent to some of the fibroblasts; in addition, large amounts of somewhat fibrillar, poorly structured, dense matter are present throughout the extracellular regions. The second alteration consists of large aggregates of intracytoplasmic lipid deposits present within the majority of the fibroblasts. Third, the endoplasmic reticulum of the fibroblasts is altered in form from that of the controls. The profiles of the cisternae are round, non-continuous within the plane of section, and are less extensively developed than in the controls. An increased macrophagic activity of the histiocytes is also described. These changes are discussed in light of the available biochemical data associated with this abnormality of protein synthesis.

A Method of Maintaining Parenchymal Cells from Adult Rat Liver In Vitro

1972 ◽  
Vol 11 (1) ◽  
pp. 249-260
Author(s):  
J. ALWEN ◽  
JENNIFER J. GALLHAI-ATCHARD
Keyword(s):  
Electron Microscopy ◽  
Endothelial Cells ◽  
Protein Synthesis ◽  
Light And Electron Microscopy ◽  
Rat Hepatocytes ◽  
Adult Rat ◽  
Adult Rat Hepatocytes ◽  
Rna And Protein Synthesis ◽  
Parenchymal Cells

A method for preparing suspensions of adult rat hepatocytes suitable for maintenance in vitro is described. Cultures were established from the cell suspensions by the squash technique. Cells were examined by light and electron microscopy; histochemically for glycogen, bile, lipid and glucose-6-phosphatase; and by autoradiography for DNA, RNA and protein synthesis. Hepatocytes could be maintained in vitro for at least 3 days and began to aggregate after 1 day. Uridine and leucine were incorporated, but not thymidine. Cultures consisted mainly of hepatocytes, though reticulo-endothelial cells were sometimes present.

scholarly journals A FIBER APPARATUS IN THE NUCLEUS OF THE YEAST CELL

1966 ◽  
Vol 29 (1) ◽  
pp. 129-151 ◽  
Author(s):  
C. F. Robinow ◽  
J. Marak
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Dense Matter ◽  
Short Fiber ◽  
Yeast Cells ◽  
Acid Fuchsin ◽  
Fine Grained ◽  
New Information ◽  
Thin Electron ◽  
Iron Alum

The structure and mode of division of the nucleus of budding yeast cells have been studied by phase-contrast microscopy during life and by ordinary microscopy after Helly fixation. The components of the nucleus were differentially stained by the Feulgen procedure, with Giemsa solution after hydrolysis, and with iron alum haematoxylin. New information was obtained in cells fixed in Helly's by directly staining them with 0.005% acid fuchsin in 1% acetic acid in water. Electron micrographs have been made of sections of cells that were first fixed with 3% glutaraldehyde, then divested of their walls with snail juice, and postfixed with osmium tetroxide. Light and electron microscopy have given concordant information about the organization of the yeast nucleus. A peripheral segment of the nucleus is occupied by relatively dense matter (the "peripheral cluster" of Mundkur) which is Feulgen negative. The greater part of the nucleus is filled with fine-grained Feulgen-positive matter of low density in which chromosomes could not be identified. Chromosomes become visible in this region under the light microscope at meiosis. In the chromatin lies a short fiber with strong affinity for acid fuchsin. The nucleus divides by elongation and constriction, and during this process the fiber becomes long and thin. Electron microscopy has resolved it into a bundle of dark-edged 150 to 180 A filaments which extends between "centriolar plaques" that are attached to the nuclear envelope.

A study of wound healing in the E11.5 mouse embryo by light and electron microscopy

1993 ◽  
Vol 25 (2) ◽  
pp. 173-181 ◽  
Author(s):  
Jane McCluskey ◽  
James Hopkinson-Woolley ◽  
Baŕbara Luke ◽  
Paul Martin
Keyword(s):  
Electron Microscopy ◽  
Wound Healing ◽  
Mouse Embryo ◽  
Light And Electron Microscopy

scholarly journals Triticum aestivum in open skin wounds: cytotoxicity and collagen histopathology

2018 ◽  
Vol 39 (4) ◽  
pp. 1547
Author(s):  
Mariana Teixeira Tillmann ◽  
Cláudia Beatriz De Mello Mendes ◽  
Geferson Fischer ◽  
Antonio Sergio Varela Júnior ◽  
Cristina Gevehr Fernandes ◽  
...  
Keyword(s):  
Wound Healing ◽  
Healing Process ◽  
Control Cell ◽  
Negative Control ◽  
In Vitro Test ◽  
Skin Wounds ◽  
In Vivo Test ◽  
Collagen Formation

Phytoterapic compounds have been used in wound healing for many centuries. Nowadays, scientific evidences of phytotherapeutics is a requirement of the legislation. The scientific literature notes the need for healing topics yielding scars that are both aesthetically appealing and resistant. We aimed to evaluate the cytotoxicity of several doses of T. aestivum extract (2 mg mL-1, 4 mg mL-1, 6 mg mL-1, 8 mg mL-1 and 10 mg mL-1) in a fibroblast cell line and the healing process in an in vivo experimental model (New Zealand rabbits). For this, MTT test in 3T6 cells was performed in duplicates using MEM (0 mg ml-1) as negative control. Cell viability was calculated as: absorbance average in treatments/absorbance average in controls x 100. In vivo test was performed in 78 skin wounds in rabbits that were treated with 2 mg ml-1and 10 mg ml-1 of T. aestivum and non-ionic cream for 21 days. After this period, it was evaluated the histology using picrosorius and Gomori’s trichrome staining. Statistical analysis was evaluated using T test (Graphpad) for cytotoxicity assay, Fischer test for the gomori trichrome test (Grahpad) and Kruskal-Wallis (Statistic 9.0) for picrosirius test. The in vitro test resulted in cytotoxicity observed at 2mg mL-1 whereas cells were viable at higher doses. On the other hand, it was observed that collagen formation of wounds was more uniform with this dose than with 10mg mL-1 extract in the in vivo study. Thus, we conclude that the 2mg mL-1 T. aestivum aqueous extract dose was more efficient in the in vivo wound healing study, despite its cytotoxic effects in vitro.

Development of intercellular junctions in the pulmonary epithelium of the foetal lamb

1978 ◽  
Vol 32 (1) ◽  
pp. 307-324
Author(s):  
E.E. Schneeberger ◽  
D.V. Walters ◽  
R.E. Olver
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Tight Junctions ◽  
Lung Development ◽  
Light And Electron Microscopy ◽  
Intercellular Junctions ◽  
Intercellular Spaces ◽  
Thin Sections ◽  
Epithelial Tight Junctions ◽  
Foetal Lamb

The integrity of epithelial tight junctions in foetal mammalian lungs is essential to maintain the unique ionic composition of lung liquid, and to prevent leakage of serum proteins into peripheral air spaces. In the present study the development of intercellular junctions of the lining epithelium of foetal lamb lungs during gestation was examined by light and electron microscopy. Both thin sections and freeze-fracture replicas were examined by electron microscopy. By 39 days of gestation, epithelial tight junctions consist of a minimum of 3.1 +/− 1.6 (s.D.) and a maximum of 5.8 +/− 2.0 discontinuous rows of particles and short segments of strands on P face ridges and in complementary E face grooves, while from 58 to 76 days they are composed of a network of 4.3 +/− 1.6 to 7.7 +/− 1.9 focally interrupted P face strands. Complementary replicas show that many of the discontinuities on the P face are due to separation of junctional particles on to the E face during fracturing, and not to an absence of junctional particles. From 76 days to term, epithelial tight junctions (exclusive of upper airway epithelium which was not examined) resemble those of adult lungs, and consist of a continuous network of 4.5 +/− 2.0 to 7.5 +/− 2.5 P face strands and complementary particle-free grooves. Permeability measurements, published elsewhere, indicate that the epithelium is functionally ‘tight’ from 69 days onwards. Tight junctions in peripheral air-space epithelium, therefore, are structurally continuous and functionally ‘tight’ early in foetal lung development, and form seals at one end of long, narrow intercellular spaces; these features may be important for coupled ion and water transport. When the bounding epithelial cells become flattened, these narrow intercellular spaces remain intact as a result of complex interdigitations of adjacent cell membranes. Desmosomes were present throughout gestation near the abluminal side of the tight junctions and occasionally near the base of the intercellular space. These junctions may serve to connect cells to each other at a time when tight junctions may be mechanically weak. In addition, gap junctions are associated with tight junctions from the glandular through the canalicular stages of lung development. They disappear by 120 days when the epithelial cells are differentiated.

scholarly journals A Method of Isolating Anucleated Yeast Protoplasts Unable to Synthesize the Glucan Fibrillar Component of the Wall

Microbiology ◽  
2000 ◽  
Vol 81 (1) ◽  
pp. 111-120 ◽  
Author(s):  
Marie Kopecká ◽  
M. Gabriel ◽  
O. Nečas
Keyword(s):  
Electron Microscopy ◽  
Saccharomyces Cerevisiae ◽  
Protein Synthesis ◽  
Plasma Membrane ◽  
Light And Electron Microscopy ◽  
Sharp Contrast ◽  
Yeast Protoplasts ◽  
Inhibition Of Protein Synthesis ◽  
Reproducible Method ◽  
Fibrillar Component

A mixture of nucleated and anucleated protoplasts was produced from log-phase Saccharomyces cerevisiae by the use of snail enzymes. The mixture was separated by centrifugation, and anucleated protoplasts were studied by means of light and electron microscopy. Anucleated protoplasts did not synthesize glucan fibrils even though they seemed to contain all other basic structures in their cytoplasm, and the structure of the plasma membrane was unchanged. This was in sharp contrast to ordinary nucleated protoplasts which synthesized glucan fibrils even after inhibition of protein synthesis by cycloheximide. The reason for this behaviour of anucleated protoplasts is not clear. Such anucleated yeast protoplasts represent the first example of uniform anucleated fungi produced by a reproducible method.

scholarly journals The istant changes of the salivary glands to stress

2010 ◽  
Vol 9 (1) ◽  
pp. 31-35
Author(s):  
A. V. Gerasimov ◽  
S. V. Logvinov ◽  
V. P. Kostyuchenko
Keyword(s):  
Electron Microscopy ◽  
Salivary Glands ◽  
Guinea Pigs ◽  
Light And Electron Microscopy ◽  
Secretory Activity ◽  
Duct Cell ◽  
Cell Stress ◽  
Microwave Exposure ◽  
Submandibular Salivary Glands ◽  
Granular Ducts

Night lighting and microwave exposure have been influence on structures of stress realization. The endocrine, fotoperiodical and adaptive functions of rodent submandibular salivary glands belonging to hormone produced duct cells. To evaluate their morphofunctional state at guinea-pigs and rats using the methods of light and electron microscopy there have been analyzed striated and granular ducts. It has been revealed that instant and twenty-four-hour strengthening of duct cell stress induced secretory activity was similar. It is concluded that salivary glands take part in circadian expectations to stress.

scholarly journals WOUND HEALING AND COLLAGEN FORMATION

1970 ◽  
Vol 44 (3) ◽  
pp. 645-654 ◽  
Author(s):  
Russell Ross ◽  
Newton B. Everett ◽  
Ruth Tyler
Keyword(s):  
Wound Healing ◽  
Electron Microscope ◽  
Mast Cells ◽  
Tritiated Thymidine ◽  
Skin Wounds ◽  
Collagen Formation ◽  
Co60 Source ◽  
Neutrophilic Leukocytes ◽  
The Many ◽  
Monocytes And Lymphocytes

Healing skin wounds were studied in a series of parabiotic rats. The femurs of one parabiont of each pair were shielded whilst both animals were given 800 r from a Co60 source. The animals were wounded 3 days after irradiation. Each animal with partially shielded marrow was then given tritiated thymidine intraperitoneally daily while the cross-circulation was arrested by clamping. After the thymidine-3H had cleared the blood, the clamp was released. Animals were sacrificed, and wounds were prepared for radioautography 1, 2, and 6 days after wounding. In the wounds of the shielded animals thymidine-3H was observed in epidermis, endothelium, leukocytes, fibroblasts, and mast cells. Only neutrophilic leukocytes, monocytes, and lymphocytes were labeled, as determined by light and electron microscope radioautography, in the wounds of each nonshielded parabiont. None of the many fibroblasts present were found to contain label in the wounds of the nonshielded parabionts through the 6 day period. These observations provide further evidence that wound fibroblasts do not arise from hematogenous precursors and, therefore, must arise from adjacent connective tissue cells.

Wound Contraction in Relation to Collagen Formation in Scorbutic Guinea-pigs

Development ◽  
1956 ◽  
Vol 4 (2) ◽  
pp. 167-175
Author(s):  
M. Abercrombie ◽  
M. H. Flint ◽  
D. W. James
Keyword(s):  
Ascorbic Acid ◽  
Guinea Pigs ◽  
Wound Contraction ◽  
Skin Wounds ◽  
Collagen Fibres ◽  
Collagen Formation ◽  
Effective Force ◽  
Mobile Part ◽  
Centripetal Movement

A Wound in any mobile part of the skin of a mammal diminishes in area as it heals by a centripetal movement of the undamaged skin surrounding it. This movement, usually called wound contraction, depends on a pull exerted by the material within the wound (Lindquist, 1946; Abercrombie, Flint, & James, 1954; Billingham & Medawar, 1955). It is commonly believed that the effective force is developed by the newly formed collagen fibres. In a previous paper, however (Abercrombie, Flint, & James, 1954), we found that the course of the contraction of skin wounds in rats did not parallel the deposition of new collagen, chemically measured. This result, while certainly in no way conclusive by itself, suggested that the supposed role of collagen in contraction ought to be tested more stringently. This we have now done by measuring wounds made on guinea-pigs receiving a diet devoid of ascorbic acid.

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